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{{#Wiki_filter:}} | {{#Wiki_filter:UPDATED FSARAPPENDIX 2LGEOLOGIC INVESTIGATION OF SOILS AND THE BEDROCK SURFACE ATUNIT 2 CONTAINMENT SITE.STATIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | ||
GEOLOGIC INVESTIGATIONSofSOILS AND THE BEDROCK SURFACEat2SITESTATIONPUBLIC SERVICE COMPANY OF NEW HAMPSHIRENEW HAMPSHIREOctober 24, 1974 CONTENTS1.Purpose of I nvc stigations2.Borings Investigationsto Boring3.Trench Excavations4.Bedrock* Exposed in TrenchesA.FaultingB.Jointing5.Unconsolidated Glacial Deposits6.ConclusionsFigure 1Public Service Company of NewSite SurveyFigure 2Geologic Map Unit 2 TrenchesFigure 3Soils ProfilesUnit 2 TrenchesAppendix IBoring Log BoringAppendix IIGeotechnical Report, Reactor BoringsGeotechnical Engineers, Inc.Page12334456 GeologicalofSoils and the Bedrock SurfaceUnit 2 Containment SiteStationNew HampshireAugust and early September, 1974, four trenchesin length were excavated to bedrock on anconfiguration acrossthe area of the Unit 2 containment site at theStation,Hampshire.The bedrock in the floor of these trenches is gneissoid quartzdiorite of the pluton, which is commonly fractured atthan 3* intervals in this area by an intersecting pattern ofangle and low-angle joints. The most prominent and continuous jointse; within the containment area appears to b one which strikesdips steeply to the north, and is by smoothcoated joint surfaces.Unconsolidated overburden in the area ranges to amaximum of 16* in thickness, and is characterized by adeposit of sand-silt-cobble till locally overlain by a blanket offine sand. Glacial-marine clay lies between the till andwash to the east of the containment. covered by sand,the upper surface of the till is beveled to a gently undulating,planar erosion surface upon which rest isolated boulders rangingtoin diameter.No evidence of Recent fault displacement was observed on thesurface in the Unit 2 trenches. The sub-planarcontact horizon, which occurs in three of the four trenches, shows noevidence in these areas of static or dynamic deformation.1. Purpose of Investigations Bedrock at the site of the proposed Unit containment is largelyobscured by glacial till, glacial-marine clay andsand. Bor-ingdrilled in December 1972 to a depth of 159.2* on the verticalcenterline of Unit 2, encountered thinof structural weakness inthe diorite bedrock at intervals between elevations -75* and These zones are characterized bychlorite-richhigh-angleandclosely jointed zones in chlorite-richof the bedrock. High-angle joints indip fromtoand most commonly dipTrenching investigations over the Unit 2 site werein1974 for precautionaryto ascertain theof thedeposits in the urea and to examine the natureof jointing in the underlying bedrock surface.2.Investigations Subsequent to BoringDuring April 1974, Eoringwas drilled to a depth of 97.8*at a iocatior, 33*(True) of the centerline of2 (see Appen-dix I for boring log) . This boring encounteredwith minorchlorite coatings a variouswith a zone of smoothcoated joints-64 to -79* elevations. These joints diptoand frequently show pyrite crystal growths over the chloritesurfaces.During 1974, four inclined borings,and 18, were down around the periphery of the Unit 2containment site to develop information relative to engineering of thecontainment Logs and orientation data for these boringsare presented in a July 31, 1974 report prepared byEngineers, Inc., Winchester, Massachusetts (see II) .Boringsandalong the west and south edges ofthe containment, respectively, encountered very few chlorite-coatedjoints.polished joint atdepth inappears likely to re-present the projection to depth of a prominent chlorite-coatedangle joint which is observed on the bedrock surface to trendthrough the centerline of Unit 2. There are no anomalouslypolished joints in BoringBoringdrilled northerly across the east edge of the con-tainment site, encountered polished chlorite-coated joints intermittentlyat depths of137* and 152-156*. Some ofthese joints appear tothe prominent east-west jointwhich trends through the centerline of Unit 2. This prominent jointappears to split into a number of high-angle branches as it passeseast into the zone of influence of Boring | |||
,and(see Figure 1) .encounteredindividual jointshavecoatings.anomalously polished orrichfound,in thedepth drilled.injoint mapping of the bed-rock surfaceBoringsanddo not indicate the presence of a through-going faultinthe area of Unit 2. These borings do appear,tothat the most prominent orchlorite-coatedjoint system in thearea trends(True) through the central part of theand dipsto the north.3. Trench ExcavationsDuring August 1974, four trenches were excavated with a back-hoe to bedrock across the 'Unit 2 site, to form anwhose legs areeach203' long and intersect at right angles at thevertical centerline of the Unit. The legs trend approximately TrueNorth,Ground surfacein the area oftrenches range fromaboutto. The elevation of the bedrock surface in the floorof the trenches rangesabout -3'Stationin the East trenchtoat Stationin the South trench. Profiles of the bedrockface along the centerlines of the trenches, as surveyed by Public ServiceCompany 'of Newpersonnel, are shown on Figuresand 3.4.Exposed in the TrenchesFigure 2 shows by half-tonethe areas of bedrock mappedby J. R. Rand in the several trenches. Although the trenches wereto bedrock, throughout, the bedrock in theelevation areastoo obscured byand mud to permit the observation of jointsor other pertinentfeatures. Although much of the bedrocksurface is rough and irregular due to glacial plucking or breaking bythe backhoe, wide areas of the bedrock are locally smooth and showglacial striations.Throughout the area exposed by the trenches the bedrock con-sists predominantly of gneissoid, sometimes quartzitic, quartz dioritewhich ranges in grain size from fine- to orientations:StrikeDipStrikeDipStrikeDipNoofof'bedrock surface or the overlyingglacialin thebreccia fab-ric,isin drill corein the Unit 2 area andthroughout thearea, can beon a smooth5'ofi nThis breccia isdips steeply, is annealedcompact,andof the glaciated bedrock surface.B. Jointingon Figure 2, jointing in the bedrock is closely spaced2 containment area,a:andat less than 3'joints (greater thandips) occur in three prominentAt the centerline of Unit 2, the most continuoustrend is This set is seen----tohavechlorite-coated surfaces. __Thejointstos e t ,thejoints arestriations whichdirections ofLow-angle joints (less thanclips) appear to be somewhat morethan high-angle joints, and occurinprominentorientations:to t'ne north.characteristic&v short__lent.StrikeStrikeStrikeand SENE andand terminate against theoccur onof p l a n a r,showstriations, with no consistent striation orientationfrom joint to joint.Fromtoin the East trench, the bedrockis subject to closely-spaced jointing, and theof the bed-rocksufficiently fractured toexcavation by t'ne backhoe.Joints in this areand smooth, and show somepolishing on conchoidal surfaces. Thin gray clay fillings occur lo-cally in discontinuous patchessome joints.showno preferredand no strike direction could be determinedfor this zone.5. Unconsolidated Glacial Deposits As shown on trench profiles on Figure 3,cobble till directly overlies the bedrock surface throughout the areaexposed by the four trenches. Tillto ground surface through-out the length of the South trench, and rises locally to ground sur-face in the North trench and in the area of the Unit 2 centerline.the till does not rise to ground surface in the trenches, theupper surface of theis a gently undulating, sub-planar erosionsurface on which a layer of medium-fine sand.At the east end of the East trench, a sequence of interbedded,layered marine clays and sands lies between the and the over-lyingsand iayer. At scattered intervals in the West, Northand East trenches, isolated boulders ranging toin diameter lieenclosed insand and rest on the upper surface of the till.Subsequent to backhoe excavation of the trenches, the contacthorizon between the till and overlyingsand was exposed andcleaned by hand throughout the length of its exposure in the West,North and East trenches. The contact was inspected and photographedby J.Rand throughout its exposed length in these trenches, andits elevation determined by transit leveling along bothof each ofthese trenches. The extent of thesand deposits in the trenchand the elevations of thecontact from place to placeare shown on Figure 2.featuresobservedthiscontact in anyof the trenches to suggest either static or dynamic deformation sub-sequent to deposition of the sand on the beveled till surface. Through-out the zone of close and slippery bedrock jointing between Stationsandin the East trench, the overlyinghorizonis sub-planar and continuous. | |||
Glacioverlying the bedrock surfacetheSouth trcrich are limited to unsorted, non-layered sand-silt-cobbletill.locallya crude stratification, and nowhereexhibit structures suggestive of podeformation.6.Examination of the overburden, bedrock surface and bedrockjoints in the Unit 2 trench excavations has revealed several distinc-tive featuresare indicative of the tectonic stability of the bed-rock at the site:A.Intermittentratified horizons in the glacial tillare not displaced over joints in the underlying bedrock.B.The undulating, sub-planar erosion surface at the top ofthe till is through-going and not subject to structural offsets or otherdeformations suggestive of faulting,C.Local exposures of glacially-scoured bedrock surfaces aresmooth across joints in the bedrock.D.Slickenside striations on closely-spaced bedrock joints ex-hibit widely divergent orientations, with no preferred attitude ororientation.John R. RandConsulting Geologist FIGURES | |||
,o7BOULDERS ON TILL SURFACEOUTiASH AND BEACH SANDE SAND.SIL1.C2EBLE TILLLT: BENCIC IN TRENCH FLOCRSURVEYED ELEV. -.3,ASE CF SANTOP OF TREHCHBATE oF TAENT8 SL),**'\letak*,5e:frock ccpbisis prederninactlyof pissoid Newburgort Vetdiorite, fine- to mediurr.graine(locally ccarse hornblende \diorite, No diabase dikes WMnoted in the trench floor.PAC URVICE COUNAY Cr KW HAIPPIli&AIWA 51A10GEOLOGIC MAP UNIT 2 TRENCHESI Ow CoduiMIMI 10 UPDATED FSARAPPENDIX 2MGEOTECHNICAL REPORTPRELIMINARY REPORT. COMPRESSION TESTS ON STRUCTURAL BACKFILL AND SAND CEMENT,STATIONThe information contained in this appendix was not revised, but has beenextracted from the originaland is provided for historical information. | |||
PRELIMINARY REPORT'COMPRESSION TESTS ONSTRUCTURAL BACKFILL AND SAND-CEMENTSTATIONJanuary 24, 1978Prepared forPUBLIC SERVICE CO. OF NEW HAMPSHIREandUNITED ENGINEERS AND CONSTRUCTORS, INC.Geotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890Project 77386 1.INTRODUCTION1.1 Purpose1.2 Scope1.3 ScheduleTABLE OF CONTENTSLIST OF TABLESLIST OF FIGURES2.DESCRIPTION OF STRUCTURAL BACKFILL ANDRESULTS OF INDEX TESTS2.1 Description2.2 Grain-Size Distribution Tests2.2.1 Procedure2.2.2 Results2.3 Specific Gravity Test2.3.1 Procedure.2.3.2 Results3.MOISTURE-DENSITY RELATION TEST4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTS4.1 Procedure4.2 Stress-Strain Curves For S Tests4.3 Moduli and Poisson's Ratios For S Tests5.1 Procedure5.2 Stress-Strain Curves ForTests5.3 Moduli and Poisson's Ratio ForTests6.TESTS ON SAND-CEMENT7.COEFFICIENT OFREACTION7.1 Structural BackfillNOTATIONSTABLESFIGURESAPPENDIX ASTRESS-STRAIN CURVES FOR DRAINED TESTSAPPENDIX BSTRESS-STRAIN CURVES FOR UNDRAINED TESTSPage No.243.1 Procedure3.2 Results5. CONSOLIDATED-UNDRAINED,TRIAXIAL TESTS910101344 LIST OF TABLESTable 1Schedule of Tests on Sand-CementTable 2Consolidated-DrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 3Consolidated-UndrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 4Unconfined Tests on 2-in. Cube Samplesof Sand-Cement, 5% Cement .TableCompression Tests on 2.8-in.-diameterSamples of Sand-Cement, 5% Cement.*To be added when tests are complete. 2. DESCRIPTION OF STRUCTURAL BACKFILLAND RESULTS OF INDEX TESTS2.1 Description Beard Pit No. 5 soil is a yellowish-browngravelly sand containing about two percent fines.2.2 Grain-Size Distribution Tests Two sieve analyses were performed.The grain-size dis-tribution of Beard Pit No. 5 soil as received was first, determined. The entire sample wassieved on aNO. 4 (4.75 mm) mesh and a grain-size distribution of soilpassing the No. 4 mesh was determined.The minus No. 4 mat-erial was used for triaxial testing.2.2.1 ProcedureTo determine the grain-size distribution ofthe original soil, a representative samplewas selected, weighed and air-dried.Thesample was sieved on a mesh and ag-gregates retained were removed, weighed andseparately sieved. A representative sampleof aggregates passing the mesh wasweighed, oven-dried and washed on a No. 200mm) sieve.The soil retained on theNo. 200 sieve was oven-dried, weighed andmechanically sieved.The entire quantity of soil was then sievedon a No. 4 (4.75 mm) mesh and aggregates re-tained were removed. A representative sampleof soil passing the No. 4 mesh was oven-driedand washed on a No. 200mm) sieve.Soilretained on the No. 200 sieve was subsequentlyoven-dried, weighed and mechanically sieved todetermine the grain-size distribution of thesoil to be used for compaction and triaxialtesting.2.2.2 ResultsThe grain-size distribution curve of BeardPit No. 5 soil is presented in Fig. 1.The grain-size distribution curve of the soilpassing the No. 4 (4.75 mm) sieve is presentedin Fig. 2. 4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTSSix S tests were performed on compacted specimens ofBeard Pit No. 5 soil.Only soil passing a No. 4 sieve wasused.Specimens were compacted to 90% and 95% of the maxi-mum dry unit weight as determined by ASTM Designation D1557,Method A (Section 3).Tests were performed at effectiveconsolidation pressures of 0.5, 2.0 and 6.0 ksc (7.1, 28.4,85.3 psi).Test specimens typically had a diameter ofand a height of 6.6-in.4.1 ProcedureA predetermined quantity of air-dried soil was thoroughlymixed with distilled water to a water content of 14%.Themixture was divided in seven portions of equal weight andplaced in covered containers.The compaction was performed in seven layers within asplit mold. The mold was lined with a rubber membrane whichwas held tightly to the inside of the mold by a small vacuum.The first soil layer was placed in the mold and leveled off.A l-psi surcharge was lowered onto the soil and vibratedvertically using an Ingersoll-Rand pneumatic hammer.Thehammer provided low frequency-high amplitude vibrations.Thelayer was compacted to a predetermined height to achieve thedesired unit weight.The surcharge was removed and the soilsurface scarified. Subsequent layers were added and compactedin the same manner to form a test specimen of the desired sizeand unit weight.The mold and specimen assembly was then mounted on thebottom platen of a triaxial cell. A vacuum of approximatelyof Hg was applied to the specimen to provide support tothe specimen. The mold was removed and the diameter and heightof the specimen were measured. A second membrane was placedaround the specimen and O-rings attached to seal the membranesto the top and bottom platens.The triaxial cell was subsequently assembled and floodedwith water. A chamber pressure of 0.5 ksc was applied and thevacuum released to distilled water at atmospheric pressure.When the vacuum had dissipated, distilled water was permeatedthrough the specimen to improve saturation by displacing airvoids. A back pressure of approximately 10 ksc was utilized tocomplete saturation.B-values of 0.90 or higher were measured. | |||
..a.normalized shear stress on theplane,vs. axial strain, andThe specimen was then consolidated to the desired effectiveconsolidation pressure. Volume changes during consolidationwere measured by monitoring the flow of pore water throughthe drainage system.The test specimen was subsequently loaded axially at aconstant rate of strain of approximatelyDuringshear the specimen was allowed to drain through both ends.Volume changes were measured by monitoring the flow of porewater. Axial loads were measured with a proving ring anddeformations were monitored with an axial dial.The testwas terminated at 20% axial strain.The specimen was thenremoved and oven-dried to determine the weight of solids.4.2 Stress-Strain Curves For S Tests Results of the consolidated-drained triaxial, S, testsare plotted in terms ofb. volumetric strain,VS. axial strain.The results of individual S tests are presented in Appen-dix A and Table 2 contains the details of each S test performed.A summary of S tests performed on specimens initially com-pacted to a specific 90% compaction are plotted in Fig. 4, and95% compaction in Fig. 5.4.3and Poisson's Ratios For S TestsFigs. 6 and 7 are plots of secant modulus and Poisson'sratio, respectively, as a function of axial strain from thetriaxial S tests.Fig. 8 (top) is a plot of the initial tangent modulus andthe secant modulus at 50 of the compressive strength versusthe effective consolidation pressure,At the bottom inFig. 8 is a similar plot for the values of Poisson's ratios. 6. TESTS ON SAND-CEMENTWe herewith forward results of tests on 2-in. cubespecimens of sand-cement, so that thewill be avail-able early in this preliminary form.In Fig. 13 are plotted the stress-strain curves for un-confined tests on three replicate specimens cured for 7 days,and in Fig. 14 are the stress-strain curves for unconfinedtests on three replicate specimens cured for 28 days. De-tails of these tests are given in Table 4.The sand-cement specimens were prepared using the samesand and cement that were used at thesite for testbatches.The mixtures are shown in Figs. 13'and 14.It may be seen that the strength increased rapidly withcure time. A strength increase that is logarithmic with timewould lead to the predition of an average strength of 180psi for the specimens curedmodulus would increase to 33,800 psi.Similarly, the average | |||
: 7. COEFFICIENT OFREACTION7.1 Structural BackfillTo determine reasonable values for the coefficient ofreaction of buried pipes, the following proceduremay be used:1.Determine whether the loading condition is"drained" or "undrained." That is, will volumechanges take place during loading (drained), orwill volume changes not occur during loading(undrained) .2.Establish the allowable diametral strain ofthe pipe. That is, select a diameter-strainthat the pipe can withstand with an adequatefactor of safety. That strain may be as lowas 0.1% for stiff, brittle pipes,to 3% or 4%for flexible pipes.3.Compute the vertical effective stress in theground at the level of the middle (springline)of the pipe.4.Choose whether the expected degree of compactionof the structural backfill is 90% Modified or95% Modified.5.Given the above data, enter the appropriatetable below, and interpolate to obtain a valueofi.e., the coefficient oftimes the pipe diameter (in psi).6.Divideby the pipe diameter to obtain thevalue ofin pci (pounds/cubic inch). | |||
TABLE 2CONSOLIDATED-DRAINEDTRIAKIAL TESTSSTRUCTURAL BACKFILLBEARD PIT 5 SANDSTATIONPercent Compaction, PEffectiveBAt Max. Compressive StressModuli ASTM D1557, AConsoli-ValueDeviator AxialVolumeInitial At 50%InIn Triaxial CelldationStressStrain StrainCompac-InitialAftertionConsoli-MolddationMax.Stress0Stresspcf--13.8100.7s213.8100.9s313.8101.0s413.8106.413.5106.3S613.7106.3GeotechnicalEngineersInc.Project 7738623, 1978pcfksckscpsip si100.8100.889.990.090.00.500.971.641.310.416,2604,0500.310.43101.0101.590.190.290.62.000.955.882.380.0814,22011,0900.170.23101.3102.390.290.491.46.000.9515.057.28-0.6623,75018,7700.220.23106.4106.495.095.095.00.500.952.341.310.9213,5109, 6000.330.35106.4106.894.995.095.32.000.977.960.9221,33016,1400.170.27106.4107.394.995.095.86.000.9519.354.000.3429,15024,7400.200.27Test InitialDry Unit WeightsNo.WaterInIn Triaxial CellContentInitialAfterConsoli-MolddationPoisson's RatioInitial At 50%Stress3ca STATIONSTRUCTURAL BACKFILLBEARD PIT 5 SANDEffectiveASTMA Consoli-Value Deviator AxialEffectiveInitialAt 50%InIn Triaxial CelldationMinorCompac- InitialStressPrincipaltionConsoli-StressMolddationTest InitialDry Unit WeightsPercent Compaction, P13.7101.0101.2101.290.290.490.40.500.966.869.532.635,8303,13013.5100.6100.6100.989.889.890.12.000.907.948.333.1112,7305,760ii313.8100.8101.1102.290.090.391.26.000.9911.326.69.4.4638,11018,63013.6101.0101.2102.390.290.491.36.000.9512.245.734.7724.46019,05013.8106.3106.5106.594.995.195.10.500.9519.9113.837.2311,8707,180ii513.6106.3106.3106.694.994.995.22.000.9521.8714.537.9319,7708,39013.5106.3106.4107.294.995.095.76.000.9627.8811.58io.3544,01014,220GeotechnicalEngineersInc.Project77386January 23,1978p pcf cfpcf- ksc -ksckscpsiCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSNo.WaterInIn Triaxial CellContent Compac- Initial AfterConsoli-MolddationBAt Maximum Compressive UnitWeightWetUnconfinedStrengthpsiStrainModulusAtofPeakElasticity*psiCureTimedaysTestNo.TABLE 4UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5% CEMENTSTATION77-1124.066.70.8010,600123.972.50.9210,110126.285.30.8313,650Avg 74.82828-1127.4141.60.67126.2133.80.77126.8130.00.87Avg 135.0Avg 11,45033,33019,13022,760Avg 25,0709090-290-3*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386.January 23, 1978 FIGURES Lab. 4-3 rev. 0U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER50050IOI0.5GRAIN SIZE MILLIMETERSCOBBLESSANDCOARSEFINECOARSEMEDIUMIFINEIIGRAIN-SIZEDISTRIBUTIONTriaxialTestsBEARD PIT NO. 5SOILStructuralBackfillProject77386Jan.23,1978Fig.1New HampshirePublic Service Company ofEngineers Inc.Winchester,Massachusetts Lab. 4 - 3 rev. 028 May 74500100505I0.50.10.05GRAIN SIZE MILLIMETERSISILT OR CL AYCOARSEFINECOARSEMEDIUMIProject 77306Jan. 23, 1978Fig. 2II\-10go-20I-IIIIIIIIIIIIIIIIIJ - 7 0809020IO0IIIIIU.S. STANDARO SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER64 3I1420 30 40 50 70200II*IIIIIIIIIIIIIII\IIIIIIITriaxial TestsStructuralBackfillGRAIN-SIZE DISTRIBUTIONBEARD PIT NO. 5 SANDNO. 4 MATERIALPublic Service Company ofNew HampshireGeotechnical Engineers Inc. .Winchester, Massachusetts WATER CONTENT,As mixed before compaction0 After compaction1051 1 31 1 11 0 91 0 704122 024TESTSSTRUCTURAL BACKFILLMOISTUREDENSITYRELATION TESTBEARD PIT No.5 SOILJanuary1978 Fig. 3PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386ENGINEERS INC.WINCHESTER,MASSACHUSETTS PROJECT 77366DECEMBER, 1977 FIG. 43024681416182006.0AXIAL STRAIN, %ENGINEERS INC.VI NCH ESTER, M ASSACHUS ETTS 2.51.5.1.0TESTs40.5s52.0S66.006420-2024681416 1820AXIAL STRAIN,%TRIAXIAL TESTSSERVICE COMPANYOF NEW HAM SSV IR^EUC T U R A L B A C K F I L LDECEMBER, 1977 FIG. 5PROJECT 77386ISUMMARY OFDRAINED TRIAXIAL TESTSCOMPACTIONENGINEERS INC AXIAL STRAIN,F O RW0III30,0002 5,00020,00090% Modified Compaction10,000.IIIII00.40.60.81.01.21.42.0IIIW000.40.60.81.21.41.61.82.0IIIII95Compact ionIPUBLIC SERVICE gCOMPANYOF NEW TARPUSHfI2RET U R ENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386JANUARYTESTSA LB A C K F I L LDRAINED LOADING 1.61.82.000.20.40.60.81.01.21.4AXIAL STRAIN,TESTS90% Modified Compaction7.1psi0.20.40.60.81.01.21.41.62.0III95% Modified Compactionpsi .PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386JANUARYFig. 7,ENGINEERS INC.MASSACHUSETTS1.21 .o0.80.60.40.201.2.o0.80.60.40.20STRUCTURAL BACKFILLPOISSONS RATIOSFOR DRAINED LOADING 10020300E moduluscompactionEmodulus50%peakcompactionE modulus95% compactionE modulus atpeokcompaction95% compactionvat 50%peak95%90% compactionat 5 00.50.40.30.20.10kg(Multiply by 14.22 for psi)SERVICE COMPANYqF NEI HAMPSHIRECENGINEERS INC.YINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSUMMARY OFFSTRUCTURALILLDRAINEDTESTSPROJECT 77386FIG. 8 4678910TEST NO.0.502.0002468141618206.006.00AXIAL STRAIN , %SERVICE COMPANYSUMMARY OFTRIAXIAL TESTSOF NEW H'WWHIJRCET UR A LB A C K F I L LUNDRAINED TRIAXIAL TESTS90% COMPACTIONENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. 9 TEST NO.*3c kg/cm2kg/cm2R40.50R52.00R66.0006421214R6STRESS-STRAINR63024681012141618 20AXIAL STRAIN,%PUBLIC SERVICE COMPANYOF NEW HAMPSHIREGEOTECHNICAL ENGINEERS INC.WINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSTRUCTURAL BACK FILLPROJECT 77386SUMMARY OF CONSOLIDATED-UNDRAINED TRIAXIAL TESTS95% COMPACTIONDECEMBER,1977 FIG. 10 SECANT MODULUS,psiundrained loadingSECANT MODULUS, Es, , psiundrained loading0DXriI I.II ENGINEERS INC.*WINCHESTER, MASSACHUSETTSPROJECT 77386DECEM 8FIG.(Multiply by 14.22 for psi)00 90% Compact ion90% CompactionCompaction 95% CompactionNOTE POISSONS RATIO FOR UNDRAINEDTESTS MAY BE TAKEN AS 0.49 TO 0.50 | |||
,12080400I2345AXIAL STRAINSand-Cement Mixture (by weight):1 part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimens7 daysUnit weight after cure7-1 124.07-2 123.97-3 126.2Strain control. loading at 1.5 mm/minPublicCompanyof New HampshireEngineers Inc.Winchester,MassachusettsCOMPRESSION TESTS7-DAY CURE5% CEMENTJanuary 1978Fig. 13Triaxial TestsStationSand-CementBackfillProject 77386 | |||
.,AXIAL STRAINSand-Cement Mixture (by weight):1part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimensCured 28 daysUnit weight after cure28-1 127.428-2 126.228-3 126.8Strain control loading at 1.5Public Service Companyof New HampshireTriaxial TestsCOMPRESSION TESTSSand-CementBackfill28-DAY CURBStation5% CEMENTGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386January 1978Fig. 14.. | |||
APPENDIX A SERVICE COMPANYPROJECT 77386ENGINEERS INC.10121618201.0VOLUMESTRESS STRAINAXIAL STRAIN,%TEST90% CompactionTRIAXIAL TESTSITRAL BACK F I L LCONSOLIDATED-DRAINEDTRIAXIAL TESTDECEMBER, 1977 FIG.OF NEW HAMVTHIRITC T 2.50.5STRESS STRAIN002468101214161820AXIAL STRAIN,%TEST S290% Compaction= 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF ^EW RHAUMPCS4IR15 R A LB A C K F I L LGEOTECHNICAL ENGINEERS INC.PROJECT 77386DECEMBER, 1977 FIG. A21.50-0.5VOLUME STRAINCONSOLIDATED-DRAINEDTRIAXIAL TEST S2 2.5STRESS-1.5,VOLUME-2.0.02468101214161820AL STRAIN,%TEST S3 90Compaction3c = 6.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386DECEMBER, 1977 2.51.51.00.5064202VOLUME STRAIN681012141618AXIAL STRAIN,%TEST S495% Compaction3c = 0.5T R I A X I A L^aSERVICE COMPANYICONSOLIDATED-DRAINEDOF NEW HAMPSHIRESTRUCTURAL BACKFILLPROJECT 77386GEOTECHNICAL ENGINEERS INC .YINCHESTER,MASSACHUSETTSDECEMBER, 1977 1.5.1.00.5 . .STRESS0VOLUME STRAIN2461012141620AXIAL STRAIN,%TEST95% Compaction2.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETEST,STRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386 DECEMBER, 6PROJECT 77386I DECEMBER, 1977 FIG. A2.5STRESS STRAIN-1.024681012741618 20VOLUME STRAINAXIAL STRAIN,%TEST S695% Compaction= 6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,SEOTECHNICAL ENGINEERS INC.1TRIAXIAL TESTSSTR UCTURAL BACKLL 4.03.02.0I>3=1.64E6260 psi4050 psi.1.00.60.40.200.40.81.21.6AXIAL STRAIN,%TEST90% Compaction= 0.5CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPROJECT 77386DECEMBER,1977 FIG. A7ENGINEERS INC.MASSACHUSETTSSERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILL 8.0= 5.883E014220 psi11090 psi6.04.0I2.00-0.1-0.2-0.3-0.400.81.21.62.0AXIAL STRAIN,%TEST S290% Compaction= 2.0SERVICE COMPANYOF NEW HAMPSHIRET R I A X I A L TESTSSTRUCTURAL BACKFILLENGINEERS INC.VVINCHESTER, MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S2Expanded ScalesPROJECT 77386DECEMBER,!977 FIG. | |||
AXIAL STRAINTEST S390% Compaction6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,STRUCTURAL BACKFILLPROJECT 77386TESTSTEST S3Expanded ScalesENGINEERS INC.WINCHESTER, MASSACHUSETTS 3= 2.34E013510 psiE9600 psi= 0.3350= 0.3500.40.81.2162.0AXIAL STRAINTEST S495% Compaction= 0.5SERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILLENGINEERS INC.MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S4Expanded ScalesPROJECT 77386IFIG. | |||
TEST95% Compaction3c = 2.0TESTSSKTRUCFTURALILLPROJECT 77386CONSOLIDATED-DRAINEDTRIAXIAL TEST S5Expanded ScalesF I G .SERVICE COMPANYOF NEW HBAMPSAHIRECMASSACHUSETTSENGINEERS INC.-0.20.40.2AXIAL STRAIN,%32133016140=7.96kg/cm-psipsi8.062.I4. | |||
I-0.1-0.3,1 6 . 012.04.08.0 .AXIAL STRAINTEST95% Compaction= 6.0PROJECT 77386DECEMBER,1977 FIG.CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.NINCHESTER, MASSACHUSETTSTESTSSTRUCTURAL BACKFILL APPENDIX 246814161820AXIAL STRAIN , %-SSPA81012141618TEST90%Compactiona3c1412108606PUBLIC SERVICE COMPANYOF NEW HAMPSHIRESTRUCTURALTRIAXIALPROJECTTESTSBACKFILL77386IDECEMBER,1977CONSOLIDATED-UNDRAINEDTRIAXIAL TEST 3.53.02.51.5STRESS PA0.5TEST90% Compactiona 3c002468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSOFSHf %P ^ H^R f U RTRIAXIAL TESTA LB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. B2 1.25"1.0DO.750.25STRESS-S TRAINSPA01.00.500.751.001.251.501.752.002.252.TEST90% Compaction6.0.. 2524681214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYOF NEW HOMPSMIRE CPROJECT 77386DECEMBER, 1977 FIG.T R I A X I A L TESTSSTKRUCTFURALILLCONSOLIDATED-UIJDRAINEDTRIAXIAL TESTENGINEERS INC.WINCHESTER, MASSACHUSETTS STRESS PASTRESS0.250.500.751.001.251.501.752.002.25TESTCompaction3c6.002468101214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIALTESTSOF NEW HAMPSHIRETRIAXIAL TESTBACKFILLSTRUCTURAL,ENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG. B4PROJECT 77386 s TRESS PASTRESS-S05101520253035404550TEST90% Compactiona 3c0024681012 14 1618 20AXIAL STRAIN, %PUBLIC SERVICE COMPANYTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDO F N E ^l 0 ALY PCS1^I RUE R ATRIAXIAL TESTLB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER, 1977 FIG. B5 S ESS PA-S10121416TEST90% Compactiona 3c= 2.02468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYTRIAXIAL TESTSOS TF RNEU CHATP UHIRREA LTRIAXIAL TESTB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG.PROJECT 77386 0.502468lo14161820AXIAL STRAIN ,ENGINEERS INC..WINCHESTER,MASSACHUSETTS00.51.01.52.02.53.03.54.04.55.PROJECT 77386TEST90% Compaction6.0DECEMBER, 1977 FIG. BSTRESS PA TRIAXIAL TESTSSTRUCTURAL BACKFILLPROJECT 773860.40 . 81.21.6AXIAL STRAIN,4.01.03 . 020TEST90% Compaction= 0.53cCONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.WINCHESTER, MASSACHUSETTS 4.03.0bI20.1.0AXIAL STRAIN, %TEST90% Compactiona 3c = 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESENGINEERS INC.WINCHESTER, MASSACHUSETTS1PROJECT 77386DECEMBER,1977 CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER,19778.00.40.81.2AXIAL STRAIN,.%TEST90% Compaction ,6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREE N G I NWINCHESTER, MASSACHUSETTST R I A X I A L TESTSSTRUCTURAL BACKFILLE E R SI N C;PROJECT 77386 AXIAL STRAIN,ENGINEERS INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG00.40.81.21.68.0TEST90% Compaction= 6.0.6.03c PUBLIC SERVICE COMPANYOF NEW HAMPSHIRECONSOLIDATED-UNDRAINEDT R I A X I A L TESTSTRTAXTALISTRUCTURAL BACKFILLSCALESTEGEOTECHNICALCHNICA L ENGIENGINERSNEER SINC.INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977AXIAL STRAIN,8.02.0TEST90% Compaction.3c= 0.5 00.40.81.21.62.0AXIAL STRAIN,20164I12TEST90% Compaction3 c = 2.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERSWINCHESTER, MASSACHUSETTSTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESPROJECT 77386IDECEMBER, 1977 AXIAL STRAIN,20.016.04.012.08.000.81.21.62.0TEST90% Compaction= 6.0 kg/cm.CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER, 19773c ENGINEERS INC.1017 MAIN STREETWINCHESTERMASSACHUSETTS 01890729-1625February 14, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th FloorManchester, NH 03105 | |||
==Subject:== | |||
Interim Test Results on Sand-Cement BackfillStation | |||
==Reference:== | |||
Preliminary Report, Compression Tests onStructural Backfill and Sand-CementStation,January 24, 1978 | |||
==Dear Mr.The purpose of this letter is to present data on moduli deter-mined on sand-cement backfill at the request of United Engineersand Constructors Inc. The data herein supplements the data in thereference and will be incorporated in the completed version of thatreport.Themodulus values were submitted to Mr. Pate1ofby telephone on February 13,== | |||
1978.The stress strain curves for three unconfined compression testson cylindrical specimens are shown in the enclosed Fig. 15 and thetest data are summarized in the enclosed Table 5.The following values of the coefficient ofreactionwere computed for the cube and cylindrical specimens cured for 28days.. | |||
Mr. JohnFebruary 14, 1978FOR SAND-CEMENT BACKFILL28-DAY CURETabulated values are in psiEffectiveVerticalStress atAllowable Diameter Strain, Springline0.020.10.30.5CUBE SPECIMENS100,000CYLINDRICALSPECIMENS200,00089,00060,00036,000The stress strain curves for the cylindrical specimens show aninitial straight line portion withhigh modulus of elasticity.At axial strains of about 0.03% there is a break in the curves and asecond straight line is followed up to near the peak strength.Thetangent modulus of this second straight line portion of the curves isabout one-third of the initial modulus.Fig. 16 shows the variation ofthe secant modulus with axial strain for the unconfined tests on cylin-drical specimens.Seating problems occurred in the tests on the cube specimens, asseen in Figs. 13 and 14 of the above reference, and thus the high initialmodulus observed for the cylindrical samples was not observed for thecubes. However, the second straight line slope for the cylindricalspecimens in Fig. 15 is in good agreement with the straight line portionof the curves for the cube specimens.The compressive strength of thecube specimens is somewhat higher than that of the cylindrical specimens,probably as a result of the more significant end restraint of the cubespecimens.For these two reasons we feel that the results of tests oncubes and cylinders are consistent with each other, but that the resultsfor tests on cylinders are more reliable and should be used to establishmoduli ofreaction. | |||
Mr. JohnFebruary 14, 1978We have also provided by telephone various friction coefficientsand estimates of shear wave velocities in the compacted soil. Thesedata will be confirmed in writing at a later date.Sincerely yours,Steve J. PoulosPrincipalEncl.cc:R.YAEC w/l encl.D.w/l encl.A. Desai,w/l encl. | |||
ConfiningCompressiveStrainInitialStressStrengthAtModulus ofPeakElasticitykscpsi%psiCureTestUnitTimeNo.WeightWetdaysTABLE 5 COMPRESSION TESTS ON 2.8-IN.-DIAMETER.SAND-CEMENT SPECIMENS, 5% CEMENTSTATION2828-O-l126.20.002828-O-2124.80.002828-O-3124.10.0091.00.6588.8.0.58106.10.8075,00052,20034,30095.3Avg 50,500Geotechnical Engineers Inc.Project 77386February 7, 1978 StationTriaxial TestsProject 77386February 1978Fig. 15Engineers Inc.Winchester, MassachusettsPublic Service Company ofSand-CementBackfillSpecimens Tested:specimens28-day cureUnconfined testsStrain control loading at1.10.81.6AXIAL STRAIN ,Sand-Cement Mixture:Xa1part cement16.18 parts sand (oven-dry)2.79 parts waterCOMPRESSION TESTS2.8-IN.-DIAMETER SPECIMEN5% CEMENT, 28-DAY CURE Winchester, MassachusettsProject 77386600 .00.20.40.81.01.2STRAIN AT PEAKAVERAGE= ksAXIAL STRAIN,,Triaxial TestsSand-CementBackfillStationPublic Service Company ofNew HampshireGeotechnical Engineers Inc.February 197816SECANT MODULUS VS STRAINSPECIMENS5% CEMENT,CURE 203060500AXIAL STRAIN,, %0.20.4= | |||
ENGINEERS INC.1017 MAIN STREET. WINCHESTERMASSACHUSETTS 01890Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street-11th floor..Manchester, NH 03105 | |||
==Subject:== | |||
Interim Test Results on Sand-Cement'BackfillStation | |||
==Reference:== | |||
Preliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978Bear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letter of February 14.These triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 33 days instead ofthe intended 28 days because of the February 6, 1978 blizzard herein Boston. The test data are summarized in a revised Table 5 andthe stress strain curves are presented in Fig. 17.The modulus and strength data were estimated for 28-day curingon the basis of the rate of change of modulus and strength withtime as measured using the cube specimens (see referenced report).The estimated values of strength and modulus for 28-day cure alsoare shown in Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letter of February14. The following table lists all values obtained to date for thesand-cement specimens. | |||
FOR SAND-CEMENT BACKFILLCURE, 5% CEMENTGEOTECHNICALINC.cc:R. Pizzuti, YAEC w/l encl.w/l encl.A. Desai,w/l encl.D.. Patel,w/l encl.Mr. JohnFebruary 27, 1978Tabulated values are in psiEffectiveAllowable Diameter Strain, %VerticalStressatSpringlinepsi0.10.30.5.CUBESPECIMENS0100,000.CYLINDRICALSPECIMENS0200,00089,00060,00036,00042.7138,000163,000129,600Sincerely yours,Steve J. PoulosPrincipalGC:msEncl. | |||
TABLE 5COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%STATION372.3652.1035,00033,6003762.4033,30036931,7003641.4040,00035738,40042.742.7124.8332833283328EstimatedTestNo.days28-O-lUnitWeightWetConfiningCompressiveStrengthpsiStrainInitialatModulus ofPeakElasticitypsi126.20.00910.6575,0002828-O-2124.80.00890.5852,200.2828-O-3124.10.001060.8034,300NOTE: 1) The percentage of cement is computed as the ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.2) The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.Geotechnical Engineers Inc.Project 77386February 7, 1978Revised February 24, 1978 3= 42.7 psi0.8 IIII 0051.0I.52.02.53.03.54 . 0AXIAL STRAIN, %Project 77386Feb. 23, 1978Fig.17StructuralBackfillTriaxial Tests2.8-IN.-DIA., 5% CEMENT33-DAY CURE,=SAND-CEMENT SPECIMENSPublic Service Company ofNew HampshireEngineersWinchester,Massachusetts 1017 MAIN STREET. WINCHESTER. MASSACHUSETTS 01890729-1625March 10, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire.1000 Elm Street11th FloorManchester, NH 03105Interim Test Results on Sand-Cement Backf illStationPreliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978 | |||
==Dear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letters of February 14 and27.Three triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 28 days and weretested under a confining stress of 7.1 psi.The test data aresummarized in a revised Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letters of February14 and 27. The following table lists all values obtained to datefor the sand-cement specimens:== | |||
Mr. JohnMarch 10, 1978FOR SAND-CEMENT BACKFILL28-DAY CURE, 5% CEMENTTabulated values are in psiEffectiveVerticalAllowable Diameter Strain, Stress atSpringlinepsi0.10.30.5CUBE SPECIMENS01 0 0, 0 0 0CYLINDRICAL SPECIMENS0200,00089,00060,0007.1115,000106,00079,60042.7138,000163,000129,600*Modulus value determined at strains greater than the strain at peakcompressivestrength.Geotechnical Engineers Inc.Project 77386Revised March 6, 1978 Mr. JohnMarch 10, 1978,GEOTECHNICALINC.GC/SJP:msEncl.cc: R. Pizzuti, YAECD.A. Desai,D. Patel,Three unconfined tests were performed on cube specimens ofsand-cement cured for 90 days. The test data are summarized ina revised Table 4.The stress-strain curves for the additional tests will betransmitted as soon as they have been drafted.Sincerely yours,Steve J. PoulosPrincipal UnitWeightWetCureTimedaysTestNo.TABLE 4 UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5 % CEMENTSTATIONUnconfinedStrengthpsiStrainModulusAto fPeakElasticity*%psi28907-l124.07-2123.97-3126.228-l127.428-2126.228-3126.890-l124.490-2124.590-30.8010,6000.9210,1100.8313,650Avg 11,450141.60.67.33,3300.7719,1300.8722,760 Avg 135.00.951.080.84Avg 28,200Avg 25,07026,32027,03031,250*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386January 23, 1978Revised6, 1978 126.2124.8124.175,00052,20034,3002828-O-l2828-O-22828-O-30.0910.650.0890.580.0.1060.80TABLE 5--COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%CureTimeNo.daysUnitWeightWetConfiningCompressiveStrengthpsiStrain.InitialatModulus ofPeakElasticitypsi283333283342.742.7423722.1035,00028282 8281)372.3762.4033,3001.4040,00039,6007.11197.1134124.3The percentage ofthe ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.34,60037632,9003643640.6032,6000.9022,9000.9717,400Geotechnical Engineers Inc.Project 77386February1978Revised-February 24, 1978Revised March 6, 1978 UPDATED FSARAPPENDIX 2NGEOTECHNICAL REPORT TEST FILL STUDY OF QUARTZITE MOLE CUTTINGS The information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
William R.Senior EngineerStevePrincipalTEST FILL STUDYOFQUARTZITE MOLECUTTINGSSubmitted toPublic Service Company of New HampshireSubmitted byGeotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890July 13, 1979Project 76301 81010101111111314TABLE OF CONTENTSPage No.LIST OF TABLESLIST OF FIGURES1.INTRODUCTION1.1 Purpose1.2 Background1.3 Summary2.CONSTRUCTION OF TEST FILLS2.1 Gravelly Sand2.2 Molecuttings (Controlled Placement)2.3 Molecuttings (No Special Controls)2.4 Stratified Molecuttings and Gravelly Sand3.PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand3.2 Molecuttings (Controlled Placement)3.3 Molecuttings (No Special Controls)3.4 Stratified Molecuttings and Gravelly Sand4.PLATE LOAD TESTS5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS5.1 Grain-Size Limits5.2 Lift Thickness5.3 Determination of In-Place Dry.Density5.3.1 Gravelly Sand5.3.2Molecuttings5.4 Determination of Percent Compaction5.5 Water Content ControlTABLESFIGURESAPPENDIX ARECOMMENDEDFOR PLACEMENTAND FIELD CONTROL OF MOLECUTTINGSAPPENDIX BPLATE LOAD TESTS LIST OF TABLESTable 1Summary of Field Density TestsGravelly Sand Test FillTable 2Summary of Field Density TestsMolecuttings (Controlled Placement) Test FillTable 3Summary of Field Density TestsMolecuttings (No Special Controls) Test FillTable 4Summary of Field Density TestsStratified Molecuttings and Gravelly Sand Test FillTable 5Summary of Plate Load Tests Results LIST OF FIGURESFig. 1Plan View of Test FillsFig. 2Profile of Test FillsFig. 3Profile of Test FillsFig. 4Compaction CurvesGravelly SandFig. 5Grain Size CurvesGravelly Sand Test FillFig. 6Compaction CurvesMolecuttings.Fig. 7Grain Size CurvesSamples of MolecuttingsFig. 8Modulus of Elasticity vs Percent CompactionMolecuttings.Fig. 9Water Content Sand ConeNuclear Density MeterGravelly SandFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryGravelly SandFig.Water Content Sand Cone vs Nuclear Density MeterDet., MolecuttingsFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryMolecuttings the same percent compaction.problem was addressed byInvestigation of the resistivityINTRODUCTION1.1 Purpose The intake and discharge tunnels atStation arebeing excavated using a tunnel boring machine, more commonlytermed a mole. The excavated material from the mole is awidely-graded crushed stone commonly termed tunnel muck, which,for this report, shall be termed "molecuttings."The purpose of the test fill study was to determine if thequartzite molecuttings obtained from-the tunnel excavationscould be used for Safety and Nonsafety-Related Structural Fill.Construction of the test fills provided the opportunity to ob-serve the behavior of the molecuttings during placement andobtain data necessary to develop procedures to control the com-paction of the molecuttings during placement.1.2 Background The molecuttings from the quartzite bedrock in the tunnelsare widely-graded crushed stone containing up to 13% passingthe No. 200 sieve.The grain size curve of the molecuttingsplots below the lower limit of the Safety and Nonsafety-RelatedStructural Backfill specification.The resistivity of thecuttings is generally below the specified minimum value of10,000Thus, although the molecuttings appearedsuperior to the gravelly sand structural fill as a backfillmaterial, it was rejected because the gradation and resistivityrequirements did not comply with the specifications.Useofthe molecuttings for Safety and Nonsafety-Related StructuralFill required that selected tests be performed which would demon-strate that the molecuttings were as good or better than thepresently used gravelly sand when both materials were placed atThe Safety and Nonsafety-Related Structural Fill is usedfor backfill around pipes and conduits, under floor slabs, roads,etc.For these applications the deformation characteristics ofthe backfill will control the soil support of the pipes andsettlements of structures. One method of determining the defor-mation properties of a soil is by determining the soil modulusby the use of a plate load test.Plate load tests were performedon carefully constructed test fills consisting of (a) gravellysand, (b) molecuttings, anda test fill of essentially alter-nating layers of gravelly sand and molecuttings which herein willbe referred to as the stratified gravelly sand and molecuttings test fill The modulus from each test fill was used as a means of comparingthe desirability of the molecuttings versus the gravelly sand foruse as Safety and Nonsafety-Related Backfill.The molecuttings are widely graded and containhigh percentages of stone retained on thesieve.In manycases the percentretained on thesieve exceeds theallowable limits for the Modified AASHO compaction testThus, it was necessary to determine by means of field and labora-tory tests performed during construction of the test fill howconstruction control of the placement of the molecuttings shouldbe handled.., 1.3 Summary The results of the plate load tests indicate that thecuttings will provide superior support for pipes and structuresthan the gravelly sand currently accepted for Safety andsafety-Related Structural Fill when both materials are placed atthe same percent compaction.The molecuttings and gravelly sandwill provide about equivalent deformation properties when thepercent compaction of the molecuttings is as much as 2 to 3%lower than the gravelly sand.Therefore, the use of molecuttingsfor Safety and Nonsafety-Related Structural Fill is recommended.Further, it is recommended that the percent compaction of themolecuttings for Safety and Nonsafety-Related Structural Fill be95% andrespectively.The molecuttings used in constructing these test fills werewidely graded crushed stone with up to 7% passing the No. 200sieve.The water content of the material varied from 3 to 4% upto 10% during placement.Because of the grain-size distributioncompaction of the molecuttings was sensitive to fluctuations inthe water content of the material. Based on data obtained fromtests performed during construction of the test fills, limitationson the grain-size distribution and water content'of thecuttings during placement have been recommended in Section 5.Construction of the test fills indicated that placement ofthe molecuttings can be controlled by modifying standard testingprocedures.The in-place dry density can be measured using thenuclear density meter and the laboratory reference dry densitydetermined by modifying the currently specified compaction tests.Details of the construction of the test fills, performanceand results of the plate load tests, and procedures for controlof placement and compaction of molecuttings are presented in thefollowing sections. 2.CONSTRUCTION OF TEST FILLSFour test fills were constructed for this study.Theorientation of the test fills is shown in Fig. 1.The soilsand details of placement for each test fill is presented below.2.1 Gravelly Sand Gravelly sand satisfying the requirements for Safety andNonsafety-Related Structural Fill Specifications 9763-8-5 and9763-8-4 was placed in 8-in. -thick loose lifts and compactedto a minimum of 95% of the maximum dry density as determined byASTM D1557, Method D.Satisfactory compaction was generallyachieved by applying water to the surface of the loose lift andcompacting with six coverages with the Mikasa double drum roller.Eight lifts of gravelly sand were placed and compacted, result-ing in a total height of about 4 ft.2.2 Molecuttings (Controlled Placement)The construction of this test fill was controlled to achievethe compaction requirements of Safety and Nonsafety-RelatedStructural Fill (i.e., 95% of the maximum dry density as deter-mined by ASTMMolecuttings were placed in 8-in. loose lifts and compactedto 95% compaction. To achieve 95% compaction, control of thewater content to within a few percent of the optimum water con-tent, and numerous coverages with the Mikasa double drum rollerwas required. Attempts at controlling the water content includedmixing of wet and dry molecuttings and adding water tocuttings with water contents 2 to 3% below optimum. Molecuttingsplaced at water contents several percent higher than optimumcould not achieve 95% compaction until sufficient drainage hadreduced the water content to near the optimum value.Eight liftsof molecuttings were placed and compacted resulting in a totalheight of about 4 ft.2.3 Molecuttinqs (No Special Controls)Construction of this test fill involved the placement of themolecuttings with limited control of water content and a specifiedcompactive effort. The molecuttings were generally placed inG-in. loose lifts and compacted by six coverages with the Mikasadouble drum roller.In some instances, water content control waslimited to permitting drainage of a compacted layer overnight be-fore placement of the succeeding layer.Eight lifts ofcuttings were placed and compacted. 2.4 Stratified Molecuttings and Gravelly Sand The first three lifts of this test fill were constructedthe same way as the test fill of Molecuttings (No Special Con-trols). The water content of the molecuttings placed for thethird lift was about 3% higher than optimum. The surface ofthe third lift was saturated and became severely rutted duringcompaction.Sandwiching layers of gravelly sand between layersof molecuttings was done to determine (1) if the gravelly sandprovided drainage of sandwiched layers of molecuttings and (2)the feasibility of constructing a backfill of stratifiedgravelly sand and molecuttings (which may be required in thezone of frost penetration).Therefore, lifts 4 and 6 were con-structed using gravelly sand.Lift 4 was compacted with sixcoverages of the Mikasa double drum roller and lift 6 was com-pacted to at least 95% compaction. Molecuttings for lifts 5, 7and 8 were generally placed in 8-in. loose lifts with limitedwater content control and compacted with six coverages of theMikasa double drum roller. 3. PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand The percent compaction of each lift was determined by per-forming in-place density tests and laboratory compaction tests.The average percent compaction of the gravelly sand test fillwas 97.4%.The in-place density for each lift, after compaction, wasdetermined by performing two 6-in. -diameter Sand Cone (SC)tests and three Nuclear Density Metertests.Theplace density determined by the NDM was generally performed atprobe depths of 4 in. and 8 in.The two SC tests were performedadjacent to two of the NDM tests to provide a comparison of thewater content and dry density measured by each 'method.The SCand NDM tests were generally performed within a 5-ft radius ofthe plate load test location. .One-point compaction samples were obtained adjacent to theSC and NDM test locations. The one-point samples were compactedin accordance with ASTM D1557, Method D.The maximum dry densityfor the one-point sample was determined by plotting the one-pointdry density on a family of curves for the gravelly sand and in-terpolating the maximum dry density.The percent compaction wascomputed by dividing the in-place dry density by the correspondingone-point compaction determined maximum dry density.Table 1presents the summary of the percent compaction achieved in thetest fill.A profile of the test fill and the average percentcompaction for each lift is shown on Fig. 2.Three compaction tests were performed in accordance withASTM D1557, Method D, on bag samples of gravelly sand obtainedfrom material placed in lifts 2, 4 and 7.The compaction curvesand related grain-size curves performed by Pittsburgh Testing Labsare shown on Figs. 4 and 5, respectively.3.2 Molecuttings (Controlled Placement)The average percent compaction achieved for this test fillwas 96.7%.The in-place density of each lift after compactionwas determined by performing several NDM tests and, when thesoil conditions were acceptable, oneSC test.The SC test was performed adjacent to a NDM test to provide acomparison of the water content and dry density measured by eachmethod. Observations in the field and data from tests indicatedthat the hole excavated for the SC test tended to squeeze in orreduce in volume when the molecuttings were placed and compacted at water contents above or near optimum.Results from the SCtests when these conditions existed gave unreasonably high drydensities, and, as a result, SC tests were considered valid onlywhen they were performed in areas where the water content of themolecuttings was less than 5%. A more complete discussion ofthis problem is presented in Section 5.The SC and NDM testswere generally performed within about a 5-ft radius of the plateload test.Generally, several NDM tests were required before a lift ofthe molecuttings was compacted to a dry density that was esti-mated to provide 95% compaction. One-point compaction sampleswere obtained adjacent to the series of NDM and SC tests that, indicated about 95% compaction had been achieved.The one-pointsamples were compacted in accordance with ASTM D1557, Method C,except the minusmaterial was included for compaction.The maximum dry density for the one-point sample was determinedby plotting the one-point dry density on a family of compactioncurves for molecuttings and interpolating the maximum dry density.Correction of the in-place dry density to account for theplusmaterial, which was removed for the laboratory test,was necessary in order to determine the percent compaction. De-tails of the correction procedure are presented in Appendix A.The percent compaction was computed by dividing the correctedin-place dry density by the corresponding maximum dry densitydetermined by the one-point compaction technique.Table 2 pre-sents the summary of the percent compaction achieved in thetest fill. A profile of the test fill and the average percentcompaction for each lift is presented in Fig. 2.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on l&-in. sieveon bag samples of molecuttings from lifts 4 and 6.The compac-tion curves and related grain-size curves are shown on Figs. 6and 7, respectively.3.3 Molecuttings (No Special Controls)The average percent compaction of this test fill was 93.0%.The water content of the molecuttings during placement was gen-erally above optimum and was not controlled during compaction.Sand Cone tests to determine the in-place dry density were notperformed because of the inaccuracy in performing the test inmolecuttings compacted at water contents near or above optimum.The in-place dry density was determined by performing at least two and most usually three to five NDM tests at probe depthsof 4 and 8 in.The NDM tests were generally performed withina 5-ft radius of the plate load test location.One-point compaction samples were obtained adjacent'to theseries of NDM tests that indicated the next lift of molecuttingscould be placed.In some cases after a lift had been compacted,NDM tests performed, and one-point samples obtained, the liftwas permitted to drain overnight and additional NDM tests takenin the morning. One-point compaction samples generally were notobtained for the NDM tests performed after drainage. The pro-cedure to compute the percent compaction for each in-place den-sity test was the same as described in the previous section.Table 3 presents the summary of the percent compactionachieved in the test fill. A profile of the test fill and theaverage percent compaction for each lift is presented in Fig. 3.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on thesieve on bag samples obtained from lifts 2A and 7A. The com-paction curves and the grain-size curve for lift 2A are shownon Figs. 6 and 7, respectively.3.4 Stratified Molecuttings and Gravelly SandThe average percent compaction of the gravelly sand andmolecuttings test fill was 92.8%.Molecuttings were used forlifts 1, 2, 3, 5, 7, and 8 for this test fill.The in-placedry density and percent compaction of the molecuttings was deter-mined in accordance with the procedure described in the previoussection. Lifts 4 and 6 of the test fill were constructed usinggravelly sand. The in-place density for lift 4 was determinedby four NDM tests. One SC test and 3 NDM tests were performedin lift 6. The maximum dry density and computation of the per-cent compaction at each in-place density test location was asdescribed in the section for gravelly sand.Table 4 presentsthe summary of the percent compaction in the test fill. A pro-file of the test fill and the average percent compaction of eachlift is presented in Fig. 3. 4.PLATE LOAD TESTSFive plate load tests were performed on the four testfills.The plate load test number, test fill and date of thetest is presented below.Plate Load Test No.Test FillDate of Test1Gravelly SandJune 7, 19792MolecuttingsJune 14, 1979(No SpecialControl) .StratifiedJune 15, 1979cuttings andGravelly SandMolecuttingsJune 18, 1979(ControlledPlacement)5Molecuttings(No SpecialControl)The locations of the tests are indicated on Fig. 1 and de-tails of the procedure are presented in Appendix B.In briefthe procedure was as follows:an-diameter steel platewas generally placed 12 in. below the surface of the test filland loaded to produce contact stresses to 4 tsf and then to 12Deflections of the plate were measured and recorded.The results of the plate load tests are presented in Figs.B2 through B6. Values of Young's Modulus, E, were calculatedfrom the results of the plate load tests using elastic theory.A description of the analysis is presented in Appendix B. Asummary of the modulus calculated for each test is presented inTable 5.The percent compaction indicated in Table 5 representsthe average percent compaction of lifts within the zone of signi-ficant stress increase due to the load on the plate.For anin. -diameter plate this zone is aboutto 36-in.-thick.The soil modulus determined by the plate load test vs per-cent compaction is plotted on Fig. 8.The results indicate thatthe molecuttingshave a much higher modulus than the gravelly sandwhen both materials are compacted to the same percent compaction.In fact, the modulus of the molecuttings compacted to 93% compac-tion is approximately equivalent to the modulus of the gravellysand placed at 97% compaction.Plate Load Test No. 5 (PLT-5) wasperformed 13 days after and about 4 ft away from Plate Load TestNo. 2 (PLT-2).The soil modulus for PLT-5 was about two timesJune 27, 1979 the modulus for PLT-2. The increase in modulus may have beencaused by densification of the molecuttings as a result ofdrainage over the 13 day period between the performance of thetwo tests. Assuming that the molecuttings were saturated afterPLT-2 and the water content reduced by 1% during a period of 13the in-place dry density would have increased by 2 to 3 pcfor about a 1 to 2% increase in the percent compaction.Themodulus for PLT-5, as a result of the densification, nearly plotson the line from PLT-2 to PLT-4.Test PLT-3 was performed on the stratified molecuttings andgravelly sand test fill. The average percent compaction of themolecuttings and gravelly sand was 92.5 andrespectively., Plate load tests, PLT-2 and PLT-1, were performed on separatetest fills of molecuttings and gravelly sands compacted to aboutthe same percent compaction and the moduli were 7,300 psi and 10,100respectively.The moduli determined for the stratified testfill, however, was 17,000 psi.Based on the results of PLT-1 andPLT-2 the anticipated modulus determined by FLT-3 was between 8and 10,000 psi.The high modulus measured by PLT-3 may have beencaused by one or more of the following factors:1.Distribution of the load may have been more rapid forthe layered fill than in a homogeneous fill, and2.Drainage of the molecuttings and related increases indry density and modulus may have accelerated faster inthe stratified test fill than in the homogeneouscuttings (No Special Controls) test fill due to drainagethrough the gravelly sand layers. | |||
: 5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS The purpose of this section is to present recommendationsfor the placement and field control of molecuttings based onfield and laboratory data obtained during construction of thetest fills.Review of the data obtained provided the information neces-sary to make recommendations on the limits for grain size, liftthickness, determination of in-place density and percent compac-tion, and control of water contents of the molecuttings. Adiscussion of each of the items is presented below.5.1 Grain-Size LimitsGrain-size analyses were performed on thre'e samples of themolecuttings used for the test fills.The grain-size curvesare presented on Fig. 7.The molecuttings were generally widelygraded with uniformity coefficients of 45 to 100.The maximumparticle size was generally less than 3-in.-diameter and thepercent by weight passing the No. 200 sieve was from 5 to 7%.Based on these and other grain-size analyses recommendations forgradation requirements were developed and are presented inAppendix A.5.2 Lift ThicknessThe molecuttings were placed in 8-in.-thick loose liftsduring construction of the test fills. Observations made duringplacement of the molecuttings indicated that the ability toachieve a specific percent compaction was mostly affected by thewater content of the material rather than the thickness of thelift. When the molecuttings were placed at water contents aboveoptimum, a specific degree of compaction generally was notachieved until the water content was reduced to'or below theoptimum water content as a result of drainage.The time requiredfor drainage is a function of the lift thickness and, therefore,where 95% and 93% compaction is required, lift thicknesses of8-in. andare recommended.Thethick loose lift inareas where 93% compaction is required was recommended based onthe fact that the average percent compaction of 93.0% was achievedfor the molecuttings (No Special Controls) test fill without thebenefit of extensive compactive efforts. | |||
5.3 Determination of In-Place Dry Density The nuclear density meterprovides a much fasterdetermination of the field in-place dry density and water con-tent than the sand cone (SC).The accuracy of the NDM testsperformed in the gravelly sand and molecuttings was verifiedby comparing the results of adjacent NDM and SC tests.5.3.1 Gravelly Sand Generally, two SC tests were performed adjacent totwo NDM tests on each lift of the test fill to com-pare the in-place dry density and water contentmeasured by each method.. The in-place water con-tent determined by the sand cone versus nuclear den-sity meter is plotted on Fig. 9.The data indicatethat both methods measure essentially the same watercontent at values less than 8% and, as the water con-tent increases, the NDM measures a lower value thanthe SC. As a result, a correction was applied tothe water content measured by the NDM to compute thein-place dry density... A plot of sand cone versusnuclear density meter determined in-place dry densityis shown on Fig. 10.The correlation of the densi-ties determined by each method was considered to bepoor.The correlation may have been improved ifmore frequent moisture checks had been performed dur-ing construction of the test fill.5.3.2Molecuttings Twelve-inch-diameter sand cone tests were performedin the molecuttings to reduce the effects that themaximum particle size and percentage of materiallarger than thesieve would have on in-place drydensity determination. The in-place dry density andwater content determined by the SC test was comparedto the results from adjacentNDM tests.Comparison of the results indicated the water contentdetermined by the NDM averaged 1.7% higher than thatdetermined by the sand cone.The 1.7% difference inwater contents was confirmed by performing water con-tent checks at random NDM test locations. A 1.7% biascorrection was applied to the water contents determinedby the NDM. A plot of sand cone determined water con-tent versus nuclear density meter water content (with a1.7% bias correction) is presented on Fig. 11. | |||
The plot shows there is a good correlation betweenthe sand cone and nuclear density meter (after biascorrection) water content determinations.A secondwater content check was made on molecuttings. afterthe test fill was completed which indicated thatthe bias had increased to 2.5%.Because the watercontent bias changed significantly within a periodof two weeks periodic checks of the bias arerecommended.The in-place dry density determined by the sand conetest and the 8-in. NDM test after correction for thewater content bias is plotted on Fig. 12.The soliddots and dashed circles represent in-place dry den-sity measurements at water contents less than 5% andgreater thanrespectively.The data indicatethat there is good correlation of dry densities deter-mined by both methods at water contents less than 5%and that the SC measured higher dry densities thanthe NDM at water contents above 5%.For this testfill the SC tests performed in molecuttings compactedat water contents above 5% are not considered validfor the reasons presented in the following discussion.When the molecuttings were placed at water contentsabove aboutthe compacted surface would exhibit aspongy behavior when one walked across the surface.The degree of sponginess increased as the moistureincreased above the optimum water content.Thesponginess is believed to be caused by water and airpore pressures. The net effect was that as the sandcone hole was excavated the pore pressures at thewalls of the hole were relieved by the walls movinglaterally into the hole until an equilibrium of thepore pressure at the walls of the hole was reached.Thus, by the time the volume of the hole was measureda significant decrease in the volume of the hole hadoccurred but the quantity of soil excavated was fromthe original volume.The result was that the dry soilexcavated was divided by awhich re-sulted in an inaccurately high computed dry density.The SC and NDM test results indicate that the NDM canbe used to determine the in-place dry density and watercontent of molecuttings. The water content bias shouldbe checked periodically to account for changes thatoccur in the molecuttings. Details of a recommendedplacement procedure arepresented in Appendix A. | |||
5.4 Determination of Percent Compaction The field and laboratory data indicated the nuclear densitymeter could be used to determine the in-place dry density afterthe appropriate water content bias had been determined for themolecuttings being tested.The preferred field procedure for determing the percent com-paction of compacted soil is as follows:1.Gbtain a one-point sample of the soil before compaction.2.Perform the' one-point compaction test in the lab anddetermine the maximum dry density from a family ofcurves.3. Perform the in-place dry density of the compacted liftusing the nuclear density meter at or near thelocation of where the one-point sample was taken.This procedure can be used for the molecuttings if at leastthree nuclear density meter determinations of the in-place drydensity are made. The average of the three tests should be usedto represent the in-place density for computation of the percentcompaction. The above procedure will reduce the effect that minorin the character of the molecuttings will have on thein-place dry density determination.The use of a standard laboratory compaction test or one whichwas slightly modified was considered the best method of deter-mining the maximum dry density of the molecuttings.The ModifiedAASHG Compaction Test, ASTM D1557, permits the use of minusmaterial to be compacted in 6-in. molds.Grain-size analysesperformed on molecuttings indicate that nearly 50% of the sampleis retained on thesieve, and, as a result, the materialpassing thesieve would behave much differently than thetotal sample during compaction. A sample of the molecuttings thatwould represent the compaction behavior of the material was con-sidered possible if the amount of coarse material removed waslimited to about 20% by weight of the total sample.This couldgenerally be achieved by removing material retained on thesieve.For the test fill the laboratory compaction used was ASTMD1557, Method C, except the plusmaterial was removed.Because this compaction test, as modified above, was used for thetest fill and gave reasonable results its use is recommended forperforming laboratory compaction tests on the molecuttings. | |||
5.5 Water Content Control The laboratory compaction curves for compaction tests per-formed on samples of molecuttings show a sharp peak in dry densityat the optimum water content, Fig. 6.The dry density drops asthe water increases or decreases from the optimum value.Thelaboratory data show that small variations in water content sig-nificantly affect the degree of compaction that can be achievedin the molecuttings. This behavior was also observed duringplacement and compaction of the molecuttings in the test fills.In the test fill where placement of the molecuttings was con-trolled, the required percent compaction generally could only beachieved by controlling the water content, by either wetting ordrying, of the molecuttings.The most efficient compaction of themolecuttings was when the water content was from about 4 to 6%.Therefore, the water content of the molecuttings should notdiffer from optimum by more than +for most efficienttion. | |||
TABLES TABLEOF FIELD DENSITY TESTS.GRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNo.SampleNo.PercentND-1One-point120.9ThiscolumnND-2samplesnot123.7doesnotap-ND-3obtained121.1plyforcompac-SC-1118.1tiontestper-formedusing2SC-111.19.7120.9123.0115.0ASTM93.5ND-24.810.0116.8120.5117.1Method D97.2SC-39.49.0120.1123.0120.397.88.19.2117.9122.0119.5N.A.13.0122.31 2 2 . 3119.23ND-1One-point123.0SC-2samplesnot126.0ND-3obtained121.4122.5N.A.I5.2I115.5122.1121.548.54.9117.8125.5119.194.98.54.9117.8125.5120.596.05.07.4119.1124.0124.1100.05.0.7.4119.1124.0118.895.8ND-55.8I7.0121.5126.0119.094.4NOTES:One-point compaction sample performed by Pittsburgh Testing Labs.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLEOF FIELD DENSITY TESTSGRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2NO.SampleNo.One-PointLaboratoryMaximumDry DensityIn-PlaceDrDensitypcfPercentCompactionPercentMaterialWaterContent%DensityForMaterial4.89.7124.5125.0125.5100.44.89.7124.5125.0123.899.05.810.3123.1124.0120.997.513.09.3126.4127.0124.998.013.09.3126.4127.0121.395.53.910.0122.3123.2117.895.613.28.4126.0127.0118.793.513.28.4126.0127.0125.799.09.17.6123.3126.5123.097.29.17.6123.3126.5126.699.75.96.8120.5126.5122.596.85.9120.5126.5123.897.910.77.8121.0124.8121.697.410.77.8121.0124.8123.298.711.37.6121.5125.8121.996.9ND-lOne-point119.6SC-2samplesnot118.9ND-3obtained120.2SC-4118.8IN.A.13.8117.9120.9116.2.NOTES:(1) One-point compaction sample performed by Fittsburgh Testing Lab.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.(3) Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geo technical Engineers Inc.Project 76301July 12, 1979 PLACEMENT)FILLTABLEOF FIELD DENSITY TESTSQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNO.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density, pcfPercent%PercentMaterialWaterContento0DryDensityTotalCorrectedForMaterial1ND-12One-pointN.A.145.5N.A.N.A.ND-13samplesnotN.A.144.0N.A.N.A.ND-14obtainedN.A.142.6N.A.N.A.ND-15N.A.146.9144.5N.A.2ND-810.85.1145.4151.0150.0146.997.324.95.1146.0151.5149.5140.993.0(1)7.3.7153.0161.5152.4150.5158.498.43ND-1011.44.6145.9152.0143.1139.091.4ND-1110.4.14.4144152.5151.8145.5152.4.150.7142.8149.898.293.999.24ND-l7.35.0151.2154.0149.4147.495.78.24.6148.3154.0148.3145.994.76.84.3144.9142.792.6.149.797.2NOTES:One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.Project 76301July 12, 1979 MOLECUTTINGS (CONTROLLED PLACEMENT) TEST FILLQUARTZITE MOLECUTTINGS STUDYTABLEOF FIELD DENSITY TESTSSTATIONPage 2 of 2LiftNo.SampleNo.One-PoirMaximumDensityIn-PlaceDensity,MaterialWaterContent%DensityCorrectedForMaterial5ND-85.64.9148.7155.0150.6149.17.74.1146.5155.0148.0145.714.54.7146.0149.4145.0.162.3160.66ND-416.94.0146.0155.0152.6146.0ND-57.84.5147.9153.0150.2148.17.54.2148.3154.0152.3150.4148.3154.07ND-412.54.9145.21 5 1 . 0147.1143.1ND-512.25.0147.5152.0149.5145.9ND-610.44.6146.3152.0147.6144.48ND-lOne-point146.0N.A.ND-2samplesnot146.5N.A.ND-3obtained146.1N.A.PercentCompaction96.294.094.895.596.897.794.896.095.0N.A.N.A.N.A.NOTES: (1) One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.July 12, TABLE 3OF FIELD DENSITY TESTSMOLECUTTINGSSPECIAL CONTROLS) TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATION 2LiftNo.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density,PercentCompactionPercentMaterialWaterContent%DensitySampleCorrectedFor +Material1ND-4One-point146.3N.A.ND-5samplesnot142.4N.A.ND-6obtained145.5N.A.ND-7149.1149.1N.A.2ND-412.34.6147.7155.0149.4145.794.0ND-510.65.8149.0152.0145.8144.595.1ND-614.55.5149.6152.0145.8142.393.6SC-712.34.6147.7155.0157.8154.591.03ND-56.06.7147.0151.0143.7141.793.8ND-69.26.2147.8151.0141.9.138.591.74ND-l10.66.5148.8151.1144.7141.193.3ND-215.56.6146.0151.0143.0137.190.85ND-l12.34.9148.9153.0150.9147.596.4ND-212.35.0148.1152.0152.2149.098.0ND-324.84.7147.7153.0140.5129.084.36ND-523.54.3153.3156.0154.2147.794.7ND-68.53.6145.1153.0145.1142.393.0ND-79.45.6153.6155.0143.3140.090.3Geotechnical Engineers Inc.Project 76301July 12, 1979 3OF FIELD DENSITY TESTS.SPECIALTEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2CompactionLaboratoryMaximumDryDensityIIn-Place Dry Density, pcfPercentCompaction%WaterContentDryDensityCorrectedForMaterial78ND-7ND-8ND-9ND-1ND-2ND-35.14.07.5One-pointsamplesnotobtained3.13.43.9141.2140.1143.6149.0148.0151.0140.0139.2148.8144.4125.0144.3138.1137.7146.6N.A.N.A.N.A.92.793.097.1N.A.N.A.N.A.Geotcchnical Engineers Inc.Project 76301July 12, 1979 4OF FIELD DENSITY TESTS STRATIFIED MOLECUTTINGS AND GRAVELLY SAND TEST FILLQLJARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 1LiftNo.SampleNo.One-PairnLaboratoryMaximumDryDensityDensity, pcfPercentPercent+Material%WaterContentDryDensityTOY-11CorrectedForMaterial3ND-715.05.7149.3153.0148.8144.194.2ND-812.26.0148.8152.0145.9141.893.35.6118.3125.0114.3N.A.91.4ND-42.7122.2124.0108.1N.A.87.2ND-53.0115.1123.0108.2N.A.88.0ND-64.9116.9124.5N.A.88.85ND-410.44.3145.7151.0151.3148.5ND-516.33.8144.8153.0138.1130.8N.A.N.A.123.31.27.5123.8N.A.97.17.2123.3127.5121.1N.A.95.0ND-36.8118.8124.5119.3N.A.95.8ND-48.3120.3124.0119.6N.A.96.57ND-104.82.7137.5148.0140.2138.493.58ND-4Onepoint147.3N.A.N.A.ND-5samplesnotobtained140.8N.A.N.A.NOTES :construction or Lift.(2)Values represent percentmaterial.(3)Nuclear density probe may have penetrated gravelly sand layer below.(4) One one-point compaction sample obtained for SC-1 and ND-2.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLE 5SUMMARY OF PLATE LOAD TESTS RESULTSQUARTZITE MOLECUTTINGS STUDYSTATIONLoadNo.SoilAtTestSoilModulus,psiAveragePercentCompaction1R e m a r k sVirginReload1GravellySand97.12Mole92.6(NoSpecialControl)3StratifiedAve. PercentMoleCuttingsandGravellyCompaction93.7Sand4Mole95.3(ControlledPlacement)5MoleCuttings(NoSpecialPerformed13daysafterControl)PLT-2Geotechnical Engineers Inc.Project 76301July 11, 1979 FIGURES PLAN VIEWTEST FILLSic ServiceofProjectStudyMolecuttingsPLT-3GravellycuttingsSandStratified Mole-cuttings andGravelly Sand(ControlledPlacement)LT-5PLT-4PLT-1PLT-2cuttings(No SpecialNot To Scale PROFILE OF GRAVELLY SANDTEST FILLSteel PlateLift 7 Ave.Comp. = 97.5Lift 6 Ave.Comp. = 97.0Lift 5 Ave.Comp. = 98.1. Lift 2Ave.% Comp. = 97.4Lift 1 Ave.Corns. = 99.0Lift 4 Ave.= 96.2Lift 3 Ave. % Comp. = 100.6Scale:= 2.5'1. One-point compaction samples not obtained.Average percentcompaction is based on maximum dry density provided by PTL.PROFILE OF MOLECUTTINGS(CONTROLLED PLACEMENT) TEST FILLSteel PlateAve.Comp. = 95.3Lift 6 Ave. %= 96.7Lift 5 Ave.Comp. = 95.0Lift 4 Ave. % Comp. = 95.1Lift 3 Ave.= 95.7Lift 2 Ave.96.2Lift 1 Ave.Comp. = N. A.Scale:= 2.5'Molecuttings l -PROFILE OF TEST_ FILLSProject 7630111, PROFILE OF MOLECUTTINGS(NO SPECIAL CONTROLS) TEST FILLLift 1 Ave.Comp. = N.A.Scale:= 2.5'PROFILE OF STRATIFIED MOLECUTTINGSAND GRAVELLY SAND TEST FILLServiceofIMolecuttingsIPROFILE OFFILLSStudyProject11, 19g .Steel Plate (PLT-2and 5)Lift 8 Ave.=Lift 7 Ave.= 94.3Lift 6 Ave.Comp. = 92.7Lift 5 Ave.Comp. = 92.9Lift 4 Ave.Comp. = 92.1Lift 3 Ave. % Comp. = 92.8Lift 2 Ave.Comp. = 94.7.Steel Plate (PLT-3)Lift 8 Ave. % Comp. = N.A.Lift 1 Ave.= N.A.Scale:2.5' U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDRCMETER6432IofLabs.Pro-iIGrain-size analyses per 'formed,..COBBLESCOARSEIFINECOARSEMEDIUMIFINEWINCHESTERMASSACHUSETTS3 4 6GRAIN SIZE MILLIMETERSSIZEQuartziteMolecuttingsGRAVELLY SANDStudyITEST FILLIIi11, 1979 NOTE: 1. Compaction test performed inwithC,the plusmaterial. was discarded and no limitationplaced on the percent retained on thePublic Service Company ofNewhireQuartzite MolecuttingsStudyProject 76301. COMPACTION CURVESMolccuttingsJuly 12, 1979Molecuttings- V W - -ControlledMolecuttings(No Special Controls)(Controlled Placement)Lift 4s = 100%-Gave = 2.83 (De152..02468IOWater Content, U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETERGRAIN SIZE MILLIMETERSCOBBLESSANDFINEGRAIN SIZESAMPLES OFMOLECUTTINGSQuartziteMolecuttingsstudyICOARSE FINE COARSEMEDIUMWINCHESTER . MASSACHUSETTSanalyses performedusing successive elutriation.MOLECDTTINGSMOLECUTTINGSLIFT 2LIFT 4I -I - -500100505I0.561(No Special Controls4 32I820 30 40 50 70200MOLECUTTINGS(Controlled Placement)(ControlledPlacement)0.050.001 | |||
.MOGravelly Sand302520151050PERCENT COMPACTIONVERSUS9092349698100Percent ofof Modified AASHO, %NOTES: 1. Modulus of elasticity computed using theory of elasticityfor semi-infinite, isotropic soil.2.Modulus of elasticity value plotted is minimum value fromvirgin loading curve.3.Percent compaction is the average percent compaction ofthe first three layers of soil under the plate.4.Percent compaction the average percent compaction of twolayers of molecuttings and one layer of gravelly sand.5.Range in percent compaction is estimated.See discussion in text.Public Service Company ofQuartziteMolecuttingsStudy76301 4.06.08.014.0Nuclear Density Meter Determined In-Place Water Content,WATER CONTENTSAND CONE VSDENSITY METERGRAVELLY SANDJu98 . 06 . 0Estimated Line ofGravelly SandBest Fit Gravelly Sandr11114116118122124126Density Meter Determined In-Place Dry Density, pcfNOTES: 1. In-place dry density includes plusmaterial. .2.In-place dry density based on 8-in. deep nuclear test.Densitieshave been corrected for water content bias according to plot ofversusnuclear for gravelly sand:conedevice3.Cone and Nuclear Density Meter determinations were performedto each other (about 6-12 in. apart).SAND CONE VS NUCLEAR DENSITY METER DET.DRY DENSITYGRAVELLY SAND10.-.--.----PublicCompany of.Elcwi L-CIIIIIQuartzitestudyProject 76301 Nuclear Density Meter DeterminedWater Content,(after bias was corrected)8 . 07 . 06 . 0Molecuttings3.04.05.06.07.08.0NOTES: 1. In-place water content is baseddeep nuclear test. | |||
135145150155160Nuclear Density Meter Determined In-Place DryDensity,NOTES: 1. In-place dry density is uncorrected for the plusmater2..except where noted.3.Water content of Sand Cone was greater than 5.0%.4.In-place density is based on 4-in. deep nuclear test.MolecuttingsPublic Service Company ofSAND CONE VS NUCLEARiSITY METER DET. IN-PLACEDRY DENSITYMOLECUTTINGSI.QuartziteMolccuttingsStudyProject 7630111, APPENDIX ASAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35in.75-1032-O22-o10-O2.The uniformity coefficient,should be notless than 5.B.PLACEMENT1.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 95% of maximum dry densityas determined by ASTMwith exceptions fortesting noted in Section C.2.2.The water content of the molecuttings should be atoptimum1% during placement. The water contentduringof quartzite molecuttings shouldbe stockpiled or otherwise treated to reduce thewater content to less than 6%.If the water contentis less thanthe addition of water during com-paction will be necessary if satisfactory compactionis to be achieved.3.Molecuttings should not be placed in direct contactwith pipes, culverts, or other structures sensitiveto abrasion and/or high point loads.4.The pore fluid of the molecuttings is brackish and,as a result, the resistivity of the muck is likelyto be below the minimum limit of 10,000United Engineers is to develop recommendations forplacement of the molecuttings in areas when highresistivity of backfill material is required. | |||
C.TESTING AND FIELD CONTROLDue to anticipated variations in rock type thecuttings should be monitored daily by determining thegrain-size distribution, water content, and rock typefor at least one typical sample.The grain-sizeanalysis should be performed by using a wet sievingtechnique and every tenth test should be performedby using the elutriation method, without pre-dryingof the sample. The frequency of testing may be re-duced in time after those testing become familiar withthe material and thus capable of judging when thematerial is or is not acceptable.a.If the percent passing thesieve materialis greater thanthe material should not beused.b.If the water content is greater than 1% aboveoptimum, the molecuttings should be stockpiledor treated to reduce the water content to optimum.2.A family of at least three compaction curves should bcdeveloped using ASTM D1557, Method C, except that theminusmaterial shall be used. Each compactioncurve should be accompanied by a grain-size analysis.Additional compaction curves should be performed onceevery 7,500 yards or earlier if visual changes in themolecuttings grain size is observed.3.A bag sample of the molecuttings should be obtainedafter the loose lift has been placed and before com-paction begins. The sample should be large enough toperform a laboratory one-point compaction test and tomeasure the percent material retained on the l&inchsieve.4.Separate the plusmaterial and calculate itspercentage by weight of the entire sample.5.A one-pointtest should be'performed on thebag sample of molecuttings in accordance with ASTMD1557, Method C, except that the minussievematerial shall be used.The maximum dry density for this sample, yd , is determined by plotting thepoint dry on the family of curves and inter-polating the maximum dry density for the minusmaterial.6.The in-place dry density should be determined by per-forming at least three nuclear density meter tests.The average dry density should be used to computethe percent compaction.This method should reduce theeffects of sharp variations in the molecuttings on thein-place dry density determinations.a. The water content bias for the nuclear densitymeter should be corrected for use in molecuttings.The water content bias should be checked weekly.7.The percent compaction is determined by dividing thecorrected in-place dry density by the laboratory maxi-mum dry density as determined in 6. above. A formulato compute the corrected in-place dry density, tocorrect for the quantity of plusmaterial, ispresented below. = 1-Rwhere= corrected in-place dry density for theminussieve material= average in-place dry density determinedby using nuclear density meter= unit weight of waterG = specific gravity of molecuttingsR = percent, by weight of the total sampleretained on thesieveThe percent compaction is computed as follows:Percent Compaction P(%) =x 100.= Maximum dry density of minusmaterialdetermined in Step 5. from the family ofcurves and the one-point compaction.YND NONSAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35100-1775-10No. 2022-o10-O2.The uniformity coefficientnot be lessthan 5.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 93 of maximum dry density asdetermined by ASTM D1557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Molecuttings can be sandwiched between presently ac-cepted gravelly sand structural fill. Whencuttings and gravelly sand are alternated in the back-fill, the following limits are recommended.a.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 93maximum dry densityas determined by ASTMb.Gravelly sand should be placed in accordance withthe present specification for structural fill (i.e.,8-in. loose lifts compacted to 95% of ASTM3. The water content of theshould beoptimum1% during placement if no gravelly sand layersare present. When the molecuttings and gravelly sandare placed in alternating layers, the water content ofthe molecuttings may be permitted to be as high as 2%above optimum.If the water content of the molecuttingsexceeds the suggested limits of water content, thecuttings should be stockpiled or otherwise treated toalter the water content.If the water content is low,say 2 tothe addition of water during compactionmay be necessary to achieve satisfactory compaction. | |||
RANDOM FILLA.MATERIALThe molecuttings to be used asFill should complywith the present specification as described in Specification No.9763-8-4, Section 3.2.2 dated September 27, 1974.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 90 of maximum dry density asdetermined by ASTM Dl557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Although limits on the water content of thecuttings are not necessary, the most efficient com-paction will occur at optimum water content1%.C.TESTING AND FIELD CONTROLTesting and field control for use of molecuttings as Ran-dom Fill should be the same as outlined for Safety-Related areaswith the following exceptions:The gradation of the molecuttings should comply withpresent specifications for Random Fill.No limit on the water content of the molecuttings isrecommended.The maximum permissible water contentin the field will be dictated by the ability toachieve the required percent compaction. | |||
APPENDIX | |||
APPENDIX BPLATE LOAD TESTB-l PurposeThe plate load tests were performed to determine the de-formation characteristics of gravelly sand and molecuttings.The results of the plate load tests provided the basis forcomparison of the two materials and to determine the effectthat percent compaction has on their deformation characteristics.. B-2 ProcedureFor each test a 24-in. -diameter hole was excavated to adepth of 12 in., except for test PLT-3 which was 6 in. deep.An -diameter, thick steel plate was placed on athin layer of liquid hydrous stone which was placed directlyon the bottom surface of the test hole. Additionalsteel platesandin diameter were placed in apyramid arrangement on top of theplate.After the hydrous stone and plates were in place, theplate was loaded by a hydraulic jack reacting against the under-side of a loaded, flat-bed trailer, as illustrated in Fig. B-l.The loads were measured using a calibrate pressure gage.Deformations of the plate were measured using three dialindicators attached to a reference beam as illustrated in Fig.B-l. The dial indicators were graduated to mm. The ref-erence beam supports were separated from the center the plateby about 72 in., which was a sufficient distance for deflectionsunder the supports to be negligible during loading of the plate.The loading sequence for each test was as follows:1.Applied load to develop contact stress of 4 tonsper square foot (tsf) in four equal increments.2.Unload to zero load in two equal increments.3.Repeat load-unload cycle to 4 tsf.4.Load to develop contact stress of 12 tsf in sixequal increments. | |||
EDS-2-5.Unload to zero load in three equal increments.6.Repeat load-unload cycle to 12 tsf two more times.Each loading or unloading increment was held constantuntil the rate of deformation of the plate was less than.001The air temperature when the plate load tests were per-formed was aboutF.B-3 ResultsThe load versus displacement curves for the five plate loadtests are illustrated in Figs. B-2 through B-6.The slope ofthe virgin load curve was generally straight except for testPLT-2 and PLT-3 where slight curvature was observed.The slopeof the reload curves were much flatter than the virgin curveand the slopes of the repeated reload-unload cycles were parallelas would be expected.Values of Young's Modulus, E, were calculated from the re-sults of the plate load tests using elastic theory.The solutionfor the settlement of a loaded, rigid circular plate on anelastic half space is as follows:where s = settlementq = average stress on the plateP = load on the plateD = diameter of the plate= Poisson's ratioI = influence factor =E = Young's ModulusAssuming a value v = 0.3 and rearranging to compute E, yields:The modulus calculated is the average modulus within the zoneof significant stress which for anplate would extend between18 to 36 inches beneath the plate.The moduli calculated using this method are presented in TableFor each test tangent moduli were calculated using the straightsegments of the load and reload curves. | |||
PLATETEST EQUIPMENTWINCHESTER .Project 76301Julv 12, 1979PublicofNew HampshireReaction Structure (Loaded Flat-bed Trailer)\ LiquidHydrousStoneBearing PlatesDial IndicatorBeamRefBeamSupportof Test FillNOTE: 1.Depth for PLT-3 was about 6-in.Schematic Illustration of Plate Load Test Equipment--(Not ToDialSteel Bearing PlateDial"Ear" Welded To Bearing PlateDial indicatorsandmonitored displacement of "ears" attachedto circumference of bearing plate.Plan---Locations of Dial Indicators(Not ToStudy 6 . 07 . 08 . 002.06.08.0. 10.012.0Vertical Stress. tsfDate Performed:June 7, 1979By:Fisher/R. GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONPLATE LOAD TESTGRAVELLY SAND...11I 802.04.06.010.012.0icof.QuartziteProject 76301StudyPLATETEST PLT-211.Vertical Stress, tsfDate Performed:June 14, 1979By:GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONCON.) | |||
41.2.3.04.06.08.0Vertical Stress, tsfDate Performed:June1979By: W. Fisher/R. GardnerPlate Diameter:Company of10.012.0VERTICALVSMolecuttingsStudyPLATE LOAD TEST PLT-3ST.GR.76301i 04 . c04.06.08.010.012.cVertical Stress, tsfDate Performed:June 18, 1979By:Fisher/R.GardnerPlate Diameter:MolecuttingsPLATE LOAD TEST PLT-4. . . . --a.---1.02.03.0DEFORMATIONStudy 02.04.06.08.010.012.0..Vertical Stress, tsfDate Performed:June1979By:FisherPlate Diameter:- -.STRESS VSDEFORMATIONPLATE LOAD TEST PLT-5MOLECUTTINGS -(NO SP. CON.-July 11,g .1 . 0.2 . 04 . 05 . 06.07.0IIIIIQuartziteStudy TABLESUMMARY OF FIELD DENSITY TESTSPageLiftSampleOne-PointCompactionLaboratoryIn-Place Dry Density, pcfNo.No.PercentWaterMaximumTotalCorrectedCompactionMaterialContentDensityDry DensitySampleForMaterialoa00% | |||
UPDATED FSARAPPENDIX 20GEOTECHNICAL REPORT DISCUSSION OF DERIVATION OFCOEFFICIENTS OFREACTIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
March 22, 1978Project 77386File No. 2.01017 MAIN STREET. WINCHESTER. MASSACHUSETTSMr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th Floor.Manchester, NH 03105 | |||
==Subject:== | |||
Discussion of Derivationof Coefficients ofReaction | |||
==Dear Mr.In the following we describe some techniques that we havedeveloped to convert the moduli obtained from triaxial tests tomoduli ofreaction for various loading conditions. Wepresent this information to complement various telephone con-versations with D. Pate1 ofComputation of Coefficients ofReactionThe coefficient ofreaction,== | |||
represents soildeformation, due to pressure acting along a boundary surface,as if the soil were composed of independent springs, each repre-senting a unit of area with a spring constantThe springconstant is defined as a pressure divided by a displacement.Such a representation is convenient for analytical purposes butneglects the influence of adjacent loaded surface areas on thedisplacement of any given point on the boundary surface.Thus,the coefficient ofreaction is not a unique number foran elastic material but is a function of the size of the loadedarea, the pressure distribution, and the geometry ofmaterial.For a soil, the modulus ofreaction is also dependent onthe method or sequence of loading, i.e., the stress path.On the basis of the theory of elasticity, wecomputedcoefficients ofreaction for the structural backfill andthe sand cement for three geometries of loading using the modulusof elasticity and Poisson's ratio data obtained in the triaxialtest results. The geometries of loading studied are illustratedin Figs. 1 through 9 and are as follows: | |||
Mr. JohnMarch 22, 19701.Circular or square footing subjected to vertical load.2.Pressure inside a cylindrical cavity in the soil massassuming a plane strain condition.This istive, for example, for the loading produced by thermalexpansion of the cross section of a buried pipe.3.Pressure inside a cylindrical cavity with simultaneousapplication of a vertical surcharge, p, and a horizon-tal pressure,This loading is an approximate re-presentation of the placement of fill over a buriedwhich deforms to produce an increased lateralstress around the pipe.A plane strain condition was.assumed.The modulus of elasticity and Poisson's ratio used in the compu-tations are strain dependent and were selected for the average strainin the region of the soil mass that contributes most to the displace-ments, namely, within a distance of one diameter from the pipe and onefooting width below the footing base. These strains were correlatedwith the displacements which, in turn, were expressed in terms offooting settlement divided by6/B, or in terms of thediameter strain of the pipe,In Figs. 1 through 9, the values ofthe coefficient ofreaction are plotted as a function of (T/Borand confining pressure. Confining pressure is to be taken asthe effective overburden pressure computed at the elevations shown inthe figures. An exception to the above procedure is that for the sur-charge type loading, a constant Poisson's ratio of 0.3 was used.The elastic modulus E and Poisson's ratio v used as a basis forthe coefficient of reaction computations were obtained fromtriaxial compression tests in which the minor principal stresses werekept constant and the major principal stress was increased monotoni-cally until the specimen failed. Such a stress path would be sufficientto determine E and v for an elastic material.However, soil is notelastic and E and v are dependent on the stress path or stress history.In particular, higher values of E would be obtained for repeated orcyclic loading. For the static load conditions, we feel that the valuesofreaction presented are reasonable estimates for the in-situloading conditions. As shown in the next section, the values comparewell with values given in published literature.We recommend, however,that when these values are used, sensitivity analyses should be made toassure that the designs are safe for a range 25% above and below thegiven values.Comparison With Published Coefficients ofReactionThe coefficients ofreaction obtained from thetestswere compared with data presented by K. Terzaghi in the paper entitled PrincipalGC/SJP:msEncl.ccR.YAECD.A. Desai,D. Patel,Mr. JohnMarch 22, 1978"Evaluation of Coefficients ofReactionGeotechnique,vol. 5, 1955, pp. 297-326.For shallow footings the vertical coefficient ofre-action for a one square foot plate, is estimated by Terzaghito range between 300 and 1,000 ton/cu ft for dense sands, i.e., arange for x B of 4,000 to 14,000 psi. These values are intendedfor shallow footings,a typical depth of embedment, Dof 4ft, and for a width, B, of one foot.Thus, they areof confining pressures equivalent to a depth of 4.5 ft or about 4 psi.The coefficient of horizontalreaction is given byTerzaghi for a 1 sq ft vertical area at a given depth, and it isassumed to be proportional to the effective stress at that depth.For example, for dense sands at a confining pressure of 10 psi, arange ofof 7,000 to 14,000 psi is indicated..Thedata for structural backfill, for strains of aboutFigs. 1, 2, 4 and 5, agree with Terzaghi's data.No specific infor-mation on strain level is given by Terzaghi for his data, but heindicates that the data are applicable to a factor of safety againstbearing capacity failure that is larger than two.It is also implicitthat the factor of safety would not be much more than 2.Perhaps itlies in the range of 2 to 4.For such factors of safety, the resultsof plate load tests on sands (1 sq ft plate) would indicate typicalsettlements of 0.1 in. to 0.3 in., which would be equivalent to avertical strain on the order of 1% in the soil adjacent to the plate.Thus, the data for the structural backfill obtained from the triaxialtests correspond to coefficients ofreaction within therange given by Terzaghi.Sincerely yours,GEOTECHNICAL ENGINEERS INC.Steve J. PoulosPrincipal FIGURES ReactionGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386Public Service Company ofNew Hampshire=March 13, 3.978Fig. 1SETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt462347Sand and Sand-CementBackfillPRESSURE ONBACKFILL90% COMPACTION ReactionSETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt B/2)..4IO'986544567 8 910234568sProject,.77386FOOTING PRESSURE ONSTRUCTURAL BACKFILL95% COMPACTIONMarch 13, 1978Fig. 2Public Service Company ofNew HampshireGeotechnicalInc.Winchester, M a s s a c h u s e t tSand and Sand-CementBackf ill 96SmSETTLEMENTk9765= EFFECTIVE VERTICASTRESS AT DEPTH445679102346789100Public Service Company ofReactionFOOTING PRESSURE ONNew HampshireSand and Sand-CementSAND-CEMENTBackf illBACKFILLEngineers Inc. ,Winchester,MassachusettsProject 77386March 13, 1978Fig. | |||
ReactionSand and Sand-CementBackf illEngineers IncWinchester, MassachusettsProject 77386Public Service Company ofNew HampshireMarch 13, 1978Fig. 4INTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILLCOMPACTIONIO'9765976541456 7 8 91023456 7 65489467 8 9102346ReactionProject 77386March 13, 1978Fia. 5Sand and Sand-CementBackf illINTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILL95% COMPACTIONPublic Servide Company ofNew HampshireGeotechnical Engineers Inc.Winchester,MassachusettsEFFECTIVE VERTICALSTRESS AT DEPTH Z2U=I IO986987463456 7 8 91023456 7 8Public Service Company ofNewGeotechnical Engineers Inc.Winchester,MassachusettsReactionSand and Sand-CementBackfillProject 77386March 13, 1978Fig. 6= EFFECTIVE VERTICALSTRESS AT DEPTHSAND-CEMENT BACKFILLINTERNAL PRESSUREPIPE BURIED INDISPLACEMENT ReactionDISPLACEMENT=98765= EFFECTIVE VERTICALSTRESS AT DEPTH4452346 7 8 9 0 0SURCHARGE PRESSURE ONPIPE IN STRUCTURALBACKFILLCOMPACTIONMarch 13, 1978Fig. 7Project 77386Sand and Sand-CementBackf illPublic Service Company ofGeotechnical Engineers Inc.Winchester, MassachusettsNew Hampshire 4567 8 910234564ReactionSand and Sand-CementBackf illProject 77386BACKFILL'95% COMPACTIONMarch 13, 1978Fig. 8ON PIPE IN STRUCTURALSURCHARGE PRESSUREInc.DISPLACEMENT= EFFECTIVE VERTICALSTRESS AT DEPTH ZPublic Service Company ofNew HampshireWinchester, Massachusetts UPDATED FSARAPPENDIX 2PSTATION CONTAINMENT AIRCRAFT IMPACT ANALYSISThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
FSARAPPENDIX 2P STATION CONTAINMENTAIRCRAFT IMPACT ANALYSISPrepared byUNITED ENGINEERSCONSTRUCTORS INC.OCTOBER 1975PUBLIC SERVICE COMPANY OF NEW HAMPSHIRESEABROOK, NEWHAMPSHIRE CONTENTSABSTRACTl-ll-ll-12l-14l-15FSARCONTENTS1.0 Structural Analysis ofStation Containmentfor Aircraft Impact l-l1.1Introduction ------------------------------1.2Forcing Function for Impacting Aircraft1.3Behavior of Containment -------1.4Response of the Enclosure Building -----1.5Shear Capability of the Containment ----1.6Requirements to Prevent Perforation ----1.7Conclusions1.8References for Section2.0 Fire Hazard Analysis ofStation 2-l2.1CombustibleVaporProduction 2-22.2FireAnalysis2-22.3Evaluation of Various Safety Related Areas 2-42.4Hazards from Smaller Aircrafti 2-62.5Conclusion2-72.6References for Section2-7l-18 SBFSARABSTRACTResults are presented which verify the adequacy of thecontainment to resist the impact of an FB-111 type aircraft.Includedis a description of the dynamic forcing function, the elastic-dynamicanalysis, the elastic-plastic analysis, an estimate of reinforcementand liner strain and a verification of the punching shear capabilityof the containment.It is shown that there existsmechanism by which spilledfuel from the impacting aircraft can access theThe ensuingfire is, therefore, postulated to start in thevicinityexternal toenclosure and it is demonstrated that these externalfires do not, in any way, inhibit or handicap the safe shutdown cap-ability of the plant following the postulated crash.It is concluded, that under the aircraft impact, the containmentstructure is able to withstand postulated impact and that the consequencesof the aforementioned fire hazard is mitigated by the inherent designfeatures ofStation. | |||
1.0 STRUCTURAL ANALYSIS OFSTATION+2l-ldxFSARAIRCRAFT IMPACT1.1 IntroductionTheStation containment has been analyzed for the effects ofa-postulated impact by an FB-111 type aircraft with a speed atimpact of 200 mph.Based on the analyses performed;-theof the containment to withstand the postulated impact is verified.TheStation containment and enclosure building is describedin Section 3.8.1 of thePSAR. The FB-111 aircraft, the missilein the postulated73.5 feet long, has a wingspanoosition) of 70.0 feet and weighs 81.800 Dounds (See Reference 1).In order to perform the analyses,a force-time relationship isdeveloped from the mechanical properties of the impacting aircraft.An elastic dynamic analysis indicates that an elastic-plasticdynamic analysis is required to predict theresponse of thestructure.From this analysis of the structure,is madeof the strains experienced by the reinforcing bars and liner.Subsequently, an analysis is performed to verify the adequacy of thecontainment against punching shear and penetration.1.2 FORCING FUNCTION FOR IMPACTING AIRCRAFTThe time variation of the load on a rigid surface due to an impactingaircraft may be developed using the momentum principle.The governingequations which are used to determine thevariation of the forceexperienced by the target are (Reference 2): | |||
FSARwhereR(t) is the force acting on the target (positive for compression),is the extent of crushing at any time t as measured from theleading edge of nose of the missile,is the load required to crush the cross section of the missileat any distance n from the nose,(positive for compression)is the mass density per unit length of the missile as a functionof the distance from the nose.These equations are used to determine the two unknowns, the crushinglength,and the reaction, R(t), as functions of time.Theinformation required to determine these variables consists of theinitial impact velocity, weight or mass distribution and crushingload distribution of the aircraft.The first equation is integrated numerically to obtain the velocitytime history. The reaction force is then determined from the secondequation.Figureshows three views of the FB-111 aircraft. Figurethe one dimensional idealized model of the same aircraft. Figure 2bdescribes the weight distribution for an FB-111 with a total weightof 81,800 pounds.The sketch and the weight distribution are obtainedfrom Reference 1.The particular configuration used is essentiallythe same as that summarized on P. 1.3.3 of Reference 1 with the wingstores and wing useful load removed.This configuration is consistenttheof the FB-111 at Pease AFB. The value of 81,800 pounds is thel-2 FSARweight before the airplane has warmed up and taken off.flights the aircraft would fly a mission and return to Pease AFB withapproximately 10,000 pounds of fuel.On this basis, the landingweight would be approximately 59,000 pounds.For those missionswhen the aircraft is flown with wing tanks the maximum take-offweight ispounds. The FB-lllis not allowed to land withfuel in these wing tanks; therefore in all cases the maximum landingweight is 81,800 pounds.Thus, the 81,800 lbs weight of the FB-111 used in the impact analysiswas the fully loaded FB-111 without wing tanks.This weight isconservatively large for any configuration of the aircraft flyingout of Pease AFB, but it was used because it represented a maximumupper bound on the weight of the FB-111 in the landing pattern.The exact crushing load distribution foran PB-111 is not available.The crushing load distribution shown onis arrived at byscaling the known values for ais demonstratedin this report that the peak value of the reaction is relativelyinsensitive to reasonable variations ofthe crushing load.Figure 3 shows the reaction-time relationship for the FB-111 strikinga rigid wall at an impact velocity of 200 mph. The peak value of thereaction is 8.2 x pounds. This peak value occurs when the wingstructure is in the process of collapsing.This peak reflects thel-3 PC8.5 x8.2 xpounds7.1 xpoundsFSARmass in the wing structurefuselage in the vicinitythenoted that the cross-sectional area overlargerthe area of fuselagesecondaryof 4.2106 pounds (atthe vicinity of the engines.The determination of the sensitivity of theto the magnitudethe crushing load is investigated bytheforvalues of one-fifth and fivethis crushing load.Theseresults are shown in Figure 4.From Figure 4,peak values of thereactions are:The peak value of the reactionrelativelv insensitive to variationsin' the magnitude of the crushing load, and the scaled value of PCjudged to give accurate results.1.3Behavior of Containment1.3.1 Elastic Dynamic Analysis For the elastic dynamic analysis, the finite element methodwas chosen as the analytical method, and a computer programfor axisymmetric structures subjected to arbitrary static anddynamic loads was used.(See Reference 3 for the basis of themechanics of the program.) Damping was not considered. Thus,the predicted structural response is slightly larger than thatwhich does occur.l-4 FSARTo accomplish the analysis, several assumptions were made.They are as follows:i)Theis fixed at the base of the cylinder.ii)Impact loads are uniformly distributed over the loadingzones.iii)In the axisymmetric analysis (impact at apex of dome), theloading zone is a circle with a radius of 52.77 inches andan area of 8748.3 square inches.iv)In the asymmetric analysis (impact at springline), theloading zone is a square,93.53 inches on a side and8748.3 square inches in area.v)The stiffness of the reinforcing steel is neglected; onlythe gross concrete volume is considered.The modulus ofelasticity was taken as 3.0 xin., Poisson'sratio was taken as 0.15, and the weight density wastaken as 150 pcf.vi)The effect of the enclosure building is neglected. Itcan be shown that the enclosure absorbs approximately 4%of the energy of the impacting aircraft.The containment structure is modeled with axisymmetric conicalshell elements, a plot of this model is shown in Figure 5.Two impact positions, the apex of the dome and the springline,are considered. The impact at the dome is uniformlydistributed over the first seven (7) elements, and the impactat the springline is uniformly distributed over the six (6)elements nearest to the springline.By means of a half-rangecosine series, the load at the springline is confined to al-5 FSAR6.18' arc.(30) terms were used to represent thisFourier series which is shown, normalized to 1.0, in Figure 6.Experience with loadings similar to the loadings here, hasdemonstrated that twenty (20) terms of the series were foundto be too few and ninetyterms were found toresultsvery close to those generated by thirtyterms.Selected maximum results for the axisymmetric and asymmetricanalyses are given in Tablesand l-2, respectively. Thesemoments will cause cracking of the concrete and yielding oftheTherefore, an elastic-plastic dynamic analysis isrequired.1.3.2' Elastic-Plastic Dynamic Analysis The procedure followed for the elastic-plastic analysis ofthe response of the containment under aircraft impact followsthat of(Reference 4). In this procedure, knowing theload-time relationship, the first natural frequency of thatpart of the structure participating in the energy absorption,and the allowable ductility ratio (defined as the ratio of themaximum deflection to the deflection at yield), the ratioof the maximum value of the load-timeto themaximum value of the resistance function can be determined. This1-6 SBFSARcan then be compared with the actual estimated maximum valuesof the load-time relationship and resistance function.The force-time relationship, given in Figure 3 is approximatedby a triangular load-time curve with the same total impulseand peak force.This ideal and the actual force-time relation-ships are compared in Figure 7 .It is assumed that a circularregion of radius "a" will participate in the energy absorption.The natural frequency, associated with this participatingregion, is estimated on the basis of the first naturalfrequency of a flat circular plate of radius "a" clamped atthe edges.The assumption of clamped edges, in that it givesa smaller period for the first natural frequency than in theactual case, is a conservative simplification. This followsbecause, in general the value of the maximum allowable forcingfunction decreases as the first natural period decreases (Ref. 4,p. 78, Figure 2.26).Conversely, ignoring the curvature isnon-conservative in that it gives an estimate*of the periodwhich is larger than the actual case.For small values of theradius "a", the curvature effect is minimal.All calculations are based upon thedome sectionconfiguration.The first natural frequency of a flat circularplate, clamped at the edge is:PX.17whereis therigidity and M is the mass density per unitsurface area (See, for example, Ref. 5).l-7 FSARthethick concrete plate with a Young's modulus ofpsi and a unit weight of 150 pounds per cubic foot,period is:sectioncracked section"a" in feet T15.94 x12.86 xUsing Fig, 2.26 of Reference 4the ratioas afunction of the radius of the participating material of thecontainment,can be determined for various values ofductility ratio.For the purpose of this investigation, two (2) ductilityratios, 3 and 10 are used. For plates and shells, the lowervalue is conservative, the larger value reasonable. Theresults of the calculations are shown in Table l-3 and Figure8.Although the range of Fig. 2.26 of Reference 4 islimited to aof 20, it can be observed that for aductility ratio greater than two and of 20, isgreater than unity. Therefore, the allowable peak force,F, can be than the maximum value of the resistance, Rm.1.3.3 Resistance FunctionIn the vicinity of the impact region, the response of thestructure is assumed to have the characteristics shown inFigureFor values of the force less than Rm, the displacements arelimited in magnitude even though the response may be inelastic.As the load reaches the valuethe deformations are ablel-8For3xthe 2+=FSARto become arbitrarily large, i.e.,the collapse load has beenreached.The collapse load for a concentrated load on acurved shell is not readily accessible.As a conservativeestimate, the collapse load for a flat plate with reinforcementthe same as the dome is used to estimate the collapse loadfor the shell..Expecting the yield line formation shown in Figureobservationsuggests that the clamped boundary condition case should beused. The value of the collapse load, Rm, is then (Referencewhereis the ultimate moment capacity and the notation + andrefers to the outside and inside reinforcement respectively.The ultimate moment capacities and collapse loads of thecontainment are:dome= 643 k-ft. /ft.651 k-ft./ft.springline= 1,235 k-ft./ftM-643 k-ft./ftAt the dome, the collapse load and peak load are approximatelyequal.However, from Figure 8 , the dynamic effect allowsthe structure to withstand loads in excess of the capacity.From Figurethe allowable load is 10% larger than theresistance or collapse load.Therefore,the apex will notl-9 FSARcollapse.Since the maximum load,less than thecapacity of the dome in the springline,collapse willnot occur at the springline.The dome will not collapse, under the applied load.1.3.4 Estimation of Rebar and Liner StrainsWhile plastic analysis techniques are useful for finding collapseloads, they cannot be directly used to find the strains anddisplacements corresponding to collapse loads.However, a procedure making use of the ductility ratio can beused to approximate the maximum strains in the structuresubject to dynamic loading when nonlinear material behavioris encountered.This procedure is described below.A typical load-displacement curve for reinforced concretesection is shown in Figure 10.This curve is linear up to theload causing crackingafter which a straight line ofsomewhat flatter slope is obtained until the loadisreached which causes yielding of the steel.Any increase in load beyondcauses the displacement toincreasedisproportionately.Further increase in load causesextensive displacements to occur,resulting in eventual collapse.This actual behavior of the structure was idealized as shown inFigureand was used for the elastic-plastic dynamic analysispreviously discussed.Thiscurve represents theresistance function of the structure.l-10 Y60 0.002FSARThe ductilityreferred to in the elastic-plasticdynamic analysis represents the ratio of the maximum displacementof the structure to the deflection established as yieldforthe structure.While it is recognized that the ductility ratio is not an exactmeasure of the maximum strain at a particular point of thestructure, it can be used as an approximation because theat yield in the actual structure is very nearly the straincorresponding to yield for the idealized structure.The procedure used herein is based on the peak of the actualforcing function resulting from the-aircraft impact, the durationof loading, theresistance function for the structureand the first natural period of the responding part of thestructure.By using the above known quantities, the correspondingductility ratio for the structure may be determined.For a peak in the forcing function of and ain the resistance function of 8,130 k, the maximum ductility ratiofor all ratios of is Fig. 2-26, Ref. 2).Thus, regardless of the natural period of the responding part ofthe structure, the largest displacement that will occur under theaircraft impact loading is the same as that to yieldfor the idealized structure.The yield strain for the reinforcing steel is SBFSARIf it is assumed that thecorresponding to yieldforthe idealized structure is 50% larger than this (actuallymuchless than this),, then an upper bound for the strain in thereinforcing steel will be:x 1.5 x 0.002 in/in =in/inSince the liner and the tension reinforcing steel are only severalinches apart in a 42" thick containment dome, they will bestrained to nearly the same values.Hence, there will be nopossibility of impairing the leak tight integrity of the liner.1.4 Response of the Enclosure Building During the early stages of the impact process, the enclosure buildingwill deform until it comes into contact with the containment. Theenclosure building must deflect five feet in order to come intocontact with the containment dome.Such a deformation will involvean inelastic response.This inelastic response will involve bothflexure and shear.The 15" thick enclosure building is reinforced withboth ways and both faces.The collapse load is 635k.The allowable shear load will depend upon the shear area over whichthe transverse shear stress acts. This shear area is determined bymultiplying the average shear periphery by the effective depth ofthe shell. The average shear periphery is determined by a contourwhich is at a distance of one-half the effective depth away from thecontour of the contact area (Figure 12 to 21 show theimpact area and shear periphery associated with various locations1-12 FSARalong the aircraft and for the effective depths of the enclosurebuilding (9") and containment (37").The reaction as a function of the cross section being crushed isdetermined from the reaction-time and crushing distance relationshipand is shown in Figure 22.From this information, it is possible to examine the effect of theaircraft impact on the enclosure building as a function of thedistance being crushed.Figure 23 shows the average shear stresson the enclosure as a function of distance being crushed.Forexample, using a shear strength of 4.25the enclosure buildingwill fail by shear when the aircraft is crushing at 7.25 feet.Alsoshown on Figure 23 is the reaction as a function of the distance beingcrushed.For a collapse load ofthe enclosure building willcollapse when the aircraft is crushing at 9.75 feet.It wouldappear that, usingas a shear strength,the enclosurewould fail by shear before collapse, however, the two eventswould occur at a time difference of 0.0086 sec. Any increase inactual shear strength abovewould increase the possibilityofand collapse happening simultaneously. Asbedomonstrated in Section 1.5, the actual shear strength can varyconsiderably above a value ofNo clear conclusion canbe drawn as to whether punch through or collapse occurs first. Basedon the above discussion, the failure of the enclosure building willinvolve both extensive shear and flexure damage and it will deformuntil it comes into contact with the containment.1-13 FSAR1.5 Shear Capability of the Containment The enclosure building will deform until it comes into contactthe containment dome.The dome will then resist the impact forceand experience transverse shear stress in the vicinity of the impactarea. The maximum average shear stress is determined by defining ashear perimeter and thickness over which the impact force is acting.Figure 24 describes the procedure by which the shear perimeter forthe maximum average shear stress acting on the containment dome isdetermined.The shear perimeter for the containment is at adistance(effective depth of enclosure) + ( effective depth of containment 2away from theof the impact area.The values of the shear perimeter for various cross sections of theaircraft are given in Table l-4.Also shown are the shear area,impact force and average shear stress for the containment building.The values of average shear stress as a function of the cross sectioncrushed is shown in Figure 25. The shear stress is given interms of psi andThe maximum value of the average shear stressoccurs when the aircraft is crushing at a distance of 35 feet fromthe nose. The value of this maximum average shear stress is 229 psiorVarious shear strengths have been proposed.A tabulation of theseshear strengths, for parameters similar to the aircraft and structureunder discussion is shown in Table l-5.It is seen that the maximumnominal shear stress ofis less than all the otherproposed values except the conservative value ofas proposed by the1-14 G1.01-15B2.570.454dmxeVWKFSARXI-Committee 326.Hence, it is concluded the the containmentwill not fail by punch through.1.6 Requirements to Prevent Perforation The velocity of the engines as they impact on the enclosure buildingand containment is 250 fps.The FB-111 has two Pratt Whitney(Military designationjet turbo fan engines with an outside diameter of 50.22inches.Each engine has a dry weight of 4,121 pounds (Ref. 1).The thickness of the dome required for no performation was determinedusing procedures reported in Reference 7.The pertinent nomenclature is :penetration thickness for infinitely thick slab (inches)perforation thickness for reinforced concrete (inches)diameter of missile (inches)velocity of impact (feet per second)weight of missile180ultimate compression strength of concrete (psi) | |||
FSARSince a jet engine is not completely solid (thin shells for torquetransmission, blades for fan, compressor and turbine, burner cans forcombustion) the engine was assumed to behave similarly to a hollowpipe missile.For a fan-jet, the outside diameter is slightly larger than the gasgenerator.Two values of dm (the diameter of the gas generator)were used, SO.23 inches and 40 inches. The results are:dm (inches)21.822.8These values can be compared with the dome thickness of 42 inches.From these calculations,can be concluded that there will be noperforation.1.7 ConclusionsFrom the above results of the analysis of theStationContainment,the following conclusions can be made:1.The enclosure building will fail and will come into contact withthe containment building.The mode of failure will not be byshear or flexure alone, but will involve both types ofdamage.2.The containment building will not fail.Thestrength willprevent collapse.The shear strength will prevent.punchThere will be permanent damage to the structure, but the extentof this damage will not be sufficient to cause loss of theintegrity of the building.l-16 FSAR3.The linerinelastic, will be sufficiently smallso that tearing of the liner will not occur.4.The engines will not perforate the containment.These conclusions can be made even though the above analysis wasperformed with considerableThe conservative aspectsof the analysis are:1.The reaction-time relationship was determined for impact on a rigidtarget. A realistic, flexible target would reduce the peak valueof the reaction.2.Normal impact was assumed.Any impact angle other thanreducesthe impact forceand increase the area over which the impactforce acts.3. The arcing effect of the doubly-curved dome was ignored. Archingincreases the collapse and punching load capacities.4.The shear stresses can be computed more accurately using theeffective forceduring the time necessary for thestructure to respond rather than the peak instantaneous force.The peak instantaneous force will give larger shear stresses thanthe effective force.5.The actual concrete compression strength will be larger than thespecified strength of 3,000 psi.This would result in a largervalue for the shear strength.6. A conservative estimate of the shear periphery used to calculateshear areas and shear strengths wasThe1-17 FSARfailure cone was assumed to be through the containment only andnot through the combined thicknesses of the containment andenclosure building,The latter would be more accurate.The integrity of the containment buildingnot be impaired in theoccurrence of the postulated aircraft impact. | |||
==1.8 REFERENCES== | |||
FOR SECTION 1.01."FB-111 Unit Inertia Data, "General Dynamics, Fort Worth Division,Report FZS-12-6010, Revision "A", January, 1968.2.Riera, J.O., "On the Stress Analysis of Structures Subjected to AircraftImpact Forces" Nuclear Engineering and Design, North Holland PublishingCompany, Amsterdam, Holland, 8p. 415-426.3.Ghosh, S., and Wilson, E., "Dynamic Stress Analysis of AxisymmetricStructures Under Arbitrary Loading", University of California,Berkeley, CA., Revised Sept., 1975.4.Biggs, J. M., Introduction to Structural Dynamics, McGraw-Hill, Inc.,1964, pps. 69-84.5. Meiorovitch, Analytical Methods in Vibrations, The Macmillan Company,1967, p. 183.6.Save and Massonnet, Plastic Analysis and Design of Plates, Shells and Disks, North Holland, 1972, p. 245.7.Kennedy, Effects of an Aircraft Crash Into a Concrete Reactor ContainmentBuilding.HolmesNarver, Inc., July, 1966.1-18 | |||
-478-478FSARTABLE l-lMAXIMUM RESPONSEANALYSIS(IMPACT AT DOME)MeridionalCircumferential Element 36 is elementabove springline.FSARTABLE 1-2RESPONSEASYMMETRIC ANALYSIS(IMPACT AT SPRINGLINE)Meridional-1139Ft-K/FtCircumferential-1309Meridional383Circumferential442Meridional-1148.Ft-K/FtCircumferential1350Meridional*378Circumferential431Element 37 is element immediately below springline. | |||
SectionTABLE l-3ALLOWABLEFORCE, MAXIM?? RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATING TARGET MATERIAL RADII31.121.2331.151.1231.201.3331.251.47Participating Radius; since this is notdefined, a range of values isincluded.** By observation, Pigure 2.26,"Introduction to StructuralRiggs-3( 1.00 x 10-29.03 x1.61 x 104.92 x 10-2T4.01 x 10-33.61 x 10-26.42 x 10-24a12162024322.51 xCracked Section41.24x137.1a4.92x10-334.2121.12x10-215.2161.99x10-2a.53-210203.11x105.43-210244.48x3.8310286.09x2.83-210327.96x102.131011.101.201.101.301.171.361.231.471.251.70170.042.418.810.6 1-4AVERAGE SHEAR STRESSLocationShear Perimeterft.ft.Shear AreaReactionpoundsAverage ShearStresspsi*If the wings were assumed to have sheared-off at the time that the aircraft were crushing at this locationthe shear perimeter and reaction would-be reduced to 64.6 ft. andrespectively. The average shearstress then becomes 198 psi.the horizontal and vertical stabilizers were assumed to have sheared-off at the time that the aircraftwere crushing at this location the shear perimeter and reaction would be reduced to 42.1 ft. andrespectively. The average shear stress then becomes 209 psi.average shear stress for the case were the crushing strength is reduced by 5 is 245 psi.32.614,47437.016,42841.818,55950.222,28899.844,31145.520,20249.221,84449.221,84415193541505889229178686,00032 Ultimate Shear StrengthpsiUltimate Shear Strength71765560752752552344539138336335129221913.111.911.089.629.589.557.146.996.626.415.334.00SBFSARTABLE l-5COMPARISON OF ULTIMATE SHEAR STRENGTH CAPACITY*equation 5-2,equation 5-1,=equation S-10,=equation 5-5,=equation 5-2,= 1equation 5-3,=equation 5-1,= 1equation S-10,= 1equation 5-5,1equationequationequation 5-6equation 5-9,326shear stress at distanced/2 from periphery = 1*"The Shear Strength of Reinforced Concrete Member-Slabs",JointTask Committee426, Journal of the Structural Division, ASCE, Aug., 1974.c = 93"= 3,000 psip = 0.0099d37"Y60,000 psi**Adjusted for circular region,evaluated at d/2 away from periphery. | |||
10 FT 3 INI.133FT., II IN.STA270.50STATICGROUND LINESTA562.97 704020Figure 2B E I G H TSB 1 2FSAR73.5---FigureI I I60040 8622FSAR TIMESECONDSFIGURE 3REACTION-TIME RELATIONSHIP 5PFSARP denotes the scale crushing load used in the calculation.and5 denotes that one-fifth and five time the crushing loadused,'respectively.1086T I M ESECONDSFIGURE 4Reaction-Time Relationship for FB-111 with impact velocities of 200 mph. | |||
SB 1 & 2FSARFIGURE 5FINITE ELDIENT MODEL FSARNO.3S T A T I O NFIGURE.6FOURIER SERIES REPRESENTATION OF SPRINGLINE LOADING 00.050.100 . 1 50.200.250.30FIGURE 7 ACTUAL AND IDEAL REACTION TIME RELATIONSHIP MATERIAL,FSARFIGURE 8ALLOWABLE MAXIMUM FORCE, MAXIMUM RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATION TARGET MATERIAL RADII SBFIGUREBEHAVIOR ANDLINE CONFIGURATION FSARFIGURE 10.LOAD-DISPLACEMENT CURVE FOR REINFORCED CONCRETE SB 1FSAR | |||
- 15.2 ft.30.2 ft.Shear PerimeterSBFSARFigure 13, Impact Area and Shear Perimeter at 8.5 Feet From Nose SBShear PerimeterEnclosure17.8 ft.Containment31.8 ft.Figure 14, Impact Area and Shear Perimeter at 9.9 feet From Nose SBShear Perimeter- -ft.Containment 32.6 ft.FigureImpact Area and Shear Perimeter at 15 Feet From Nose FSAR\\IShear PerimeterContainment37.0 ft.Figure 16, Impact Area and Shear Perimeter at 19.0 Feet From Nose Shear PerimeterContainment37 ft.FSARFigure 17, Impact Area and Shear Perimeter at 27 Feet From Nose FigureImpact Area and Shear Perimeter at 35 Feet from NoseShear Perimeter'Containment 50.2 Ft.SBFSAR | |||
...Containment - 99 8 ftShear Perimeterm.MIN********.*1.Figure 19, Impact Area and Shear Perimeter at 41.0 Feet From Nose Shear PerimeterContainmentII43.2 ft.SB2FSARFigure 20, Impact Area and Shear Perimeter at 50.0 Feet From Nose Shear PerimeterContainment 49.2 ft.Figure 21Impact Area and Shear Perimeter at 58.0 Feet From NoseFSAR IDISTANCEFEET1010304050602FIGURE 22, REACTION-CRUSHING LOCATION RELATIONSHIP JPSI6.005.0025010012345671750DISTANCE CRUSHED-FT.Figure 23 Average Shear Stress-Distance Crushed and Reaction Distance CrushedRelationship for the Enclosure Building. | |||
2Effective Shear Area24 SCHEMATIC FORSHEAR 25STRESS-DISTANCE CRUSHED RELATIONSHIP FOR CONTAINMENTDISTANCE CRUSHED229 PSI FSAR2.0FIRE HAZARD ANALYSIS OFSTATION CONTAINMENTFOR AIRCRAFT IMPACTA highly unlikely chain of adverse events is postulated in thefollowing manner:An FB-111 with a weight of 81,800 lbs and initial speed of 200mph impacts on one of the two double containment complexes of thebrook plant.The enclosure building deforms locally under the initialimpact,and the local deformation continues with little to no perforationuntil the enclosure building comes into contact with the containmentbuilding.This fact, plus the fact that if any penetration should occurit would be only the nose of the aircraft, will preclude the spillingof significant amounts of fuel into thespace. Thespacecontains no equipment,and all penetrations both mechanical and electricalare isolated from missiles and fuel by reinforced concrete slabs,Theenclosure building acts as a barrier and directs the spilled fuel to theexterior area near the enclosure building.The following effects werethen studied:Possible production of combustible vapor, its promptignition and the ensuing pressure pulse, and thepossibility that the combustible vapor may be suckedinto the plant areas and be cause for delayed ignitionor toxic atmosphere in habitability systems.The fuel spilled and its transport to various areas ofthe plant. An ignition is then postulated, and theeffect of the ensuing fire studied in order to evaluate2-l FSARthe safe shutdown capability of the plant.The effect of smoke and/or toxic gases as may be generatedby the fire, with particular reference to control roomhabitability.The effects as detailed in (1) and (3) for all smaller air-craft.2.1COMBUSTIBLE VAPOR PRODUCTION The FB-111 carries approximately 32,000 lbs of type JP-4 fuel. Asindicated in Reference 1, the process of combustible vapor production isas follows:the crashing aircraft drags along the ground in a relativelyslow deceleration (0.4 g) which lasts for a 'long' time (20and thefuel issuing from the wing after some postulated leakage mechanism isatomized to mist by the air as a result of its velocity relative to air.For the direct impact considered here,the decelerations are very high(peak value of 29 g) and of very 'short' duration (0.3 sec.).The atom-izing process under these conditions is not significant.It is, there-fore, concluded that the combustible vapor production and the associatedhazards can be considered to be mitigated.2.2FIRE ANALYSISVarious spill mechanisms are postulated either on the roofs or onthe ground adjacent to the containment structure:The various roof areas adjacent to the containment enclosurewith their elevation approximate areas, etc., are detailedin Table 2-1.As stated in PSAR Section 2.4, most of theseroofs have parapets, and the roof drainage systems aredesigned to drain at least 3 inches per hour rain. It is2-2 FSARnoted further that 1 inch of fuel takes 10 minutes toUsing the minimum area in Table 2-1, and acatastrophic instantaneous mode of fuel release, themaximum expected duration of the fire is 17.9 minutes.For ground areas adjacent to the containment, there isapproximately 1.5 acres of land, the total drainage ofwhich is approximately 6 cfs.The spreading of the fuelover this area and the adequate drainage would result ina film fire with width comparable to the roughness of thepavement, e.g.,inch.The resulting fire would lastonly for 1 minute at the most.The mechanism of fire propagation was examined. No flamm-able material is normally expected to be present next tothe containment which can serve as the propagator of thefire. The range of the fire has very conservativelyestimated to be 200 ft. from its point of origin.Smoke is postulated to be traveling from this centre firelocation carried by the wind.Its effect on the habitabilitysystems was then studied.The possible hazard of fuel getting into the PAB Buildingthrough the vent stack is considered remote due to the follow-ing reasons:The mechanism is improbable.The entering fuel will be drained off at the base ofthe vertical stack, just as rainwater would be.The possible hazard of fuel getting into the main steam linetunnels through the side vent openingsconsidered notprobable since the vent openings are above grade.2-3 FSAR2.3 EVALUATION OF VARIOUS SAFETY RELATED AREASThe various intake points to the safety related areas and theirdescription8 are detailed in Table 2-2,including the missile shieldswhen applicable, under the accident conditions detailed in Subsection2.3. All buildings other than the control room and the PAB residualheat removal area are either not needed for safe shutdown or are redun-dant.However, the conservative analysis below includes the reactionof these areas to the postulated fire.(a) Control Room There is no mechanism for the fire to endanger the habitabilityof the control room, since the split intake vents are at adistance of at least 300 ft. from the containment; therefore,it is beyond the reach of the direct fire. However, in theremote event that the fire finds its way into the intakestructure, the temperature and smoke sensors will sense itthe intake opening will be closed. Under theseconditions, the other intake will be used for ventilating thecontrol rooms.Primary Auxiliary Building (PAB) The air intake is located on the east wall of the primaryauxiliary building at an elevation ofThe area infront of the intake has the containment enclosure roofelevation ofand the east wall of the PAB faces thecontainment and the fuel storage building.There may be afire lasting 12.5 minutes at most on the roof of thecontainment enclosure area, a part of which may be injectedinto theair intake, as its height is 3 ft. above the2-4 FSARroof of containment enclosure area.The inside of thePAB has roll-type filters after the intake and heatingcoil panels after the filter.Therefore,the flame andthe hot gases would have to penetrate the filter and thecoils before reaching the fans.As indicated in Subsection 2.2, the roof surface of thecontainment enclosure area will be finished smooth andwith proper drainage to drain off the spilled fuel quickly.Smoke and heat sensors will be located at the air inlet sothat on a signal from them the operator can stop the fans.Diesel Generator BuildingThe diesel generator building intakes are on opposite sidesof the building and are located at least 180 ft. from thecontainment structures.It is considered improbable thatthe spilled fuel will find its way underneath one of theseintakes.Furthermore,the intakes are 28.5' above gradelevel, and it is unlikely that the fire will rise to thatheight.In addition, one of the intakes is shielded bythe diesel generator building and it is thus not consideredcredible that the fire could reach that intake.Althoughit may be postulated that the hot gas from thepoint may cause momentary oxygen starvation ofgenerator, the shielded intake will ensure theother diesel generator and of one train.Service Water Building direct intakeone dieselintegrity ofThe intake for the service water building is approximately280 ft. from the containment'and should be out of reach ofthe postulated fire.Furthermore,the air intake is located2-5 FSARin the east wall of the building.Consequently, thebuilding serves as a shield for the spilled fuel flow.Additionally, there is a missile shield in front of thestructure, which should inhibit any possible fuel flowand subsequent fire.The fire effects are, therefore,considered minimal. However, a minute amount of hot gasmay enter the facility, but since the pumps are locatedat the west end of the building, it will not criticallythreaten their operation due to rise of temperature.Vent StackThe vent stack is not a safety related item and, as in-dicated in Subsection 2.2, it does not furnish a significantpathway for the fuel to get into the primary auxiliary build-ing. This mechanism of fire propagation is, therefore, con-sidered incredible.Cable Spreading, Battery Room, Switch Gear Room and Cable Tunnel The air intake for cable spreading, battery room, switch gearroom and cable tunnel areas is through the mechanical equip-ment room of the diesel generator building, and the varioussafety aspects discussed for the diesel generator room holdfor this case.2.4HAZARDS FROM SMALLER AIRCRAFTThe smaller plane crashes were examined for the various areas, asdetailed in Subsections 2.2 and 2.3. The fuel in general may be JP-1,kerosene and JP-4.Since the fuel carrying capacity for all these planesis smaller than that of FB-111, and their burning temperatures are of thesame order of magnitude, it was concluded that the effect would be envelopedby those in the case of FB-111.2-6 FSARCONCLUSIONS In view of the results in Subsectionsandit was con-cluded that the hazard toStation from direct fire after thepostulated crash of an FB-111 or smaller aircrafts on the containmentrepresents only very minimal potential hazard to the plant.The presentdesign of the plant has inherent safety features so that the consequenceof this minimal hazard is mitigated.REFERENCES FOR SECTION 21.Appraisal of Fire Effects From Aircraft Crash at Zion PowerReactor Facility, I. Irving Pinkel,Consultant, Atomic EnergyCommission, July 17, 1972.Flammability Characteristics of Combustible Gases and Vapors,Bulletin 627, U. S. Bureau of Mines, 1965, Michael Zabetakis. | |||
BUILDINGSROOFAREA(SQ.FT.)ELEVATIONREMARKSCONTAINMENT ENCLOSURE4,10053'WITH PARAPETEMERGENCYFEEDWATERPUMPBLDG.3,00047'WITH PARAPETFUEL STORAGE BUILDING9,20084'WITH PARAPETPRIMARYAUXILIARYBUILDING8,14481'WITH PARAPETPAB Filter Room2,856108'WITH PARAPETTABLE 2-lROOF DESCRIPTIONSNOTE:GRADE ELEVATION 20' TABLEVENTILATION SYSTEM DESCRIPTIONS OF THE BUILDING SURROUNDING THE CONTAINMENT .,SHEET 1 OFBUILDINGBUILDINGSURFACEFACING THE CONT.LOCATIONS OF THEINTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMCONT.WALLELEVATIONDieselGen.South wallSouthWall200 ft.28.5ft.above gr.Other Bldg.at 40'dist..Ventilationair;notnecessaryforsafeshutdown.NorthWall240 ft.(thruroof)28.5 ft.aboveOther Bldg.at40PABEast wallEastWall20 ft.3aboveadjacentroof.Shielded bythe Cont.F.Stg.Bldg.Normalventilationair;only RHRpump area safeshutdownrelated.NorthWall95ft.(thruroof)29ft.above gr.thickshield.Ventilationairtosafety relatedmary component cool,ing water pump areaand Boron injectionpump area.EmergencyFeedwaterPump Bldg.South WallNorthWall30 ft.(thruroof)18ft.above gr.2'thickconcretemissileshieldVentilationairtothe emergencywater pump area. | |||
TABLE 2-2 (CONT.)SHEET 1 OF 2BUILDINGBUILDINGSURFACEFACING THE CONT.LOCATION OFTHE INTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMELEVATIONCONT.WALLServiceWaterPumpHouseWest WallEastWall290ft.(throof)ru45 ft.above2'thickmissileshield.Ventilationairtotheservice waterpump house.WestWall180ft.13.5above2'thickmissileshield.Air intake to theelectricalareas.ControlRoomComputerRoomSouth 6EastWallsRemoteIntakePorts300ft.least)At gr.levelCoveredwithgrating.Ventilationairtothe habitable areasof the control andcomputer room. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-1 APPENDIX 2Q EAB AND LPZ SHORT TERM ACCIDENT DIFFUSION ESTIMATES FOR AST 2Q.1 OBJECTIVE Conservative values of atmospheric diffusion at the site boundary (EAB) and the low population zone (LPZ) were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2Q.2 METHODOLOGY The methodology used for this calculation is consistent with Regulatory Guide 1.145 as implemented by the PAVAN computer code (Reference 2). Using joint frequency distributions of wind direction and wind speed by atmospheric stability, the PAVAN computer code provides relative air concentration (CHI/Q) values as functions of direction for various time periods at the site boundary and LPZ. Three procedures for calculation of CHI/Qs are utilized for the site boundary and LPZ; a direction-dependent approach, a direction-independent approach, and an overall site CHI/Q approach. The CHI/Q calculations are based on the theory that material released to the atmosphere will be normally distributed (Gaussian) about the plume centerline. A straight-line trajectory is assumed between the point of release and all distances for which CHI/Q values are calculated. The theory and implementing equations employed by the PAVAN computer code are documented in Reference 2. 2Q.3 CALCULATIONS/PAVAN COMPUTER CODE INPUT DATA The boundary distance used in each of the 16 downwind directions from the site was set to 914 m. The LPZ boundary distance was set to 2,011 m. All of the releases were considered ground level releases because the highest possible release elevation is from the plant stack at 185 ft above plant grade. From Section 1.3.2 to Reference 1, a release is only considered a stack release if the release point is at a level higher than two and one-half times the height of adjacent solid structures. For the Seabrook plant, the elevation of the top of the containment is 199.25 ft. Therefore, the highest possible release point is not 2.5 times higher than the adjacent containment buildings, and thus all releases were considered ground level releases. As such, the release height was set equal to 10.0 meters as required by Table 3.1 of Reference 2. The building area used for the building wake term was 2,416 m2. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-2 The tower height at which the wind speeds were measured is 10.05 m above plant grade. The windspeed units are given in miles per hour, therefore the PAVAN variable UCOR was set equal to 101 to convert the windspeeds to meters per second as described in Table 3.1 of Reference 2. The maximum windspeed in each windspeed category was chosen to match the raw joint frequency distribution data, which conforms to the windspeed bins in Table 1 of Reference 3. 2Q.4 RESULTS PAVAN computer runs for the EAB and LPZ boundary distances were performed using the data discussed previously. Per Section 4 of Reference 1, the maximum CHI/Q for each distance was determined and compared to the 5% overall site value for the boundary under consideration. For dose calculations, the most limiting 2 hour CHI/Qs were combined with the worst 2 hour EAB doses to maximize calculated EAB doses (conservative approach). The maximum EAB and LPZ CHI/Qs that resulted from this comparison are provided in the table below: Offsite Boundary /Q Factors for Analysis EventsTime Period EAB /Q (sec/m3)LPZ /Q (sec/m3) 0-2 hours 3.17E-041.54E-04 0-8 hours 2.08E-048.63E-05 8-24 hours 1.68E-046.46E-05 1-4 days 1.06E-043.45E-05 4-30 days 5.51E-051.40E-05 2Q.5 REFERENCES 1. USNRC Regulatory Guide 1.145, "Atmospheric Dispersion Models for Potential Accident Consequence Assessments at Nuclear Power Plants," Revision 1, November 1982, (Reissued February 1983 to correct page 1.145-7). 2. NUREG/CR-2858, "PAVAN: An Atmospheric Dispersion Program for Evaluating Design Basis Accidental Releases of Radioactive Materials from Nuclear Power Stations," November 1982. 3. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-1 APPENDIX 2R SHORT-TERM (ACCIDENT) DIFFUSION FOR THE CONTROL ROOM 2R.1 OBJECTIVE Conservative values of atmospheric diffusion to the Control Room were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2R.2 METHODOLOGY The ARCON96 computer code is used by the USNRC staff to review licensee submittals relating to control room habitability (Reference 1). Therefore, the ARCON96 computer code was used to determine the relative concentrations (CHI/Qs) for the control room air intakes and inleakage locations. The ARCON96 computer code uses hourly meteorological data for estimating dispersion in the vicinity of buildings to calculate relative concentrations at control room air intakes that would be exceeded no more than five percent of the time. These concentrations are calculated for averaging periods ranging from one hour to 30 days in duration. The theory and implementing equations employed by the ARCON96 computer code are documented in Reference 1. 2R.3 CALCULATIONS/ARCON COMPUTER CODE INPUT DATA Five years of meteorological data (1998-2002) were used for the ARCON96 computer code runs. The percentage of valid data over this time period was 98.8% which exceeds the minimum value of 90% data recovery specified in Reference 2. A number of various release-receptor combinations were considered for the control room CHI/Qs. These different cases were considered to determine the limiting release-receptor combinations for the various events. The case matrix for these combinations is provided in Table 2R-2. The distance and direction inputs for the ARCON96 runs may be found in Table 2R-1. The distances were converted from feet to meters with a factor of 0.3048 m/ft. The distances in meters were then rounded down to the nearest tenth for conservatism. The elevation difference term was set equal to zero for each case since all elevation points are taken with respect to the same datum. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-2 The lower and upper measurement heights for the meteorological data were entered as 10.05 m and 60.66 m, respectively, for each case. The mph option was selected for the windspeed units. A ground level release was chosen for each scenario since none of the release points are 2.5 times taller than the closest solid structure as called out in Section 3.2.2 of Reference 3 for stack releases. The top of the containment structure is at an elevation of 199.25 ft. The highest release point is from the top of the plant stack at an elevation of 185 ft., which is not 2.5 times higher than the nearby containment structure. The vertical velocity, stack flow, and stack radius terms were all set equal to zero since each case is a ground level release. The vent release option was not selected for any of the scenarios. The actual release height was used in the cases. No credit was taken for effective release height due to plume rise; therefore, for the releases from the stacks, the release elevations were set equal to the stack top elevation. The release heights were taken as the release elevations less the plant grade elevation of 19 ft. The only cases in this analysis that take credit for the building wake effect are the scenarios where the release is from the containment building, the tank farm, or the waste processing building. Some of the other scenarios have buildings between the release and receptor points, but for these cases the building wake was not credited for the sake of conservatism. Not crediting wakes was accomplished by setting the building area term equal to 0.01 m2 as stated in Table A-2 of Reference 3. The first building area used is a conservatively determined containment cross sectional area. The area is calculated as the sum of the cross sectional areas created by the cylindrical portion of the containment structure above the highest nearby roof and the hemispherical area of the dome. The width used is equal to the diameter of the containment structure. The height of the cylindrical portion is taken as the distance between the top of the cylinder portion of the containment structure (represented by the spring line elevation) and the primary auxiliary building roof elevation. The radius of the hemispherical dome is taken as one half of the calculated diameter. The containment area was determined to be 1,506 m2. The second building area is calculated as the product of the minimum roof height of the waste processing building and tank farm and one half the width of the waste processing building and tank farm. The minimum roof height and one half of the width are used for conservatism. This building area was determined to be 337 m2. All of the default values in the ARCON96 code were unchanged from the code default values with the following exceptions. Table A-2 of Reference 3 suggests use of a value of 0.2 for the Surface Roughness Length, and use of a value of 4.3 for the Averaging Sector Width Constant. These two changes were made for each case. The minimum wind speed was left at 0.5 m/s per the guidance instruction in Table A-2 of Reference 3. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-3 2R.4 RESULTS ARCON96 computer runs for the various release points and control room intake locations were performed using the data discussed previously. Per Reference 3, the 95th percentile CHI/Q values were determined. The resulting CHI/Qs are listed in Table 2R-2. 2R.5 REFERENCES 1. NUREG/CR-6331 PNL-10521, "Atmospheric Relative Concentrations in Building Wakes," May 1995, with Errata dated July 1997. 2. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. 3. USNRC Regulatory Guide 1.194, "Atmospheric Relative Concentrations for Control Room Radiological Habitability Assessments at Nuclear Power Plants," June 2003. | |||
UPDATED FSARAPPENDIX 2LGEOLOGIC INVESTIGATION OF SOILS AND THE BEDROCK SURFACE ATUNIT 2 CONTAINMENT SITE.STATIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
GEOLOGIC INVESTIGATIONSofSOILS AND THE BEDROCK SURFACEat2SITESTATIONPUBLIC SERVICE COMPANY OF NEW HAMPSHIRENEW HAMPSHIREOctober 24, 1974 CONTENTS1.Purpose of I nvc stigations2.Borings Investigationsto Boring3.Trench Excavations4.Bedrock* Exposed in TrenchesA.FaultingB.Jointing5.Unconsolidated Glacial Deposits6.ConclusionsFigure 1Public Service Company of NewSite SurveyFigure 2Geologic Map Unit 2 TrenchesFigure 3Soils ProfilesUnit 2 TrenchesAppendix IBoring Log BoringAppendix IIGeotechnical Report, Reactor BoringsGeotechnical Engineers, Inc.Page12334456 GeologicalofSoils and the Bedrock SurfaceUnit 2 Containment SiteStationNew HampshireAugust and early September, 1974, four trenchesin length were excavated to bedrock on anconfiguration acrossthe area of the Unit 2 containment site at theStation,Hampshire.The bedrock in the floor of these trenches is gneissoid quartzdiorite of the pluton, which is commonly fractured atthan 3* intervals in this area by an intersecting pattern ofangle and low-angle joints. The most prominent and continuous jointse; within the containment area appears to b one which strikesdips steeply to the north, and is by smoothcoated joint surfaces.Unconsolidated overburden in the area ranges to amaximum of 16* in thickness, and is characterized by adeposit of sand-silt-cobble till locally overlain by a blanket offine sand. Glacial-marine clay lies between the till andwash to the east of the containment. covered by sand,the upper surface of the till is beveled to a gently undulating,planar erosion surface upon which rest isolated boulders rangingtoin diameter.No evidence of Recent fault displacement was observed on thesurface in the Unit 2 trenches. The sub-planarcontact horizon, which occurs in three of the four trenches, shows noevidence in these areas of static or dynamic deformation.1. Purpose of Investigations Bedrock at the site of the proposed Unit containment is largelyobscured by glacial till, glacial-marine clay andsand. Bor-ingdrilled in December 1972 to a depth of 159.2* on the verticalcenterline of Unit 2, encountered thinof structural weakness inthe diorite bedrock at intervals between elevations -75* and These zones are characterized bychlorite-richhigh-angleandclosely jointed zones in chlorite-richof the bedrock. High-angle joints indip fromtoand most commonly dipTrenching investigations over the Unit 2 site werein1974 for precautionaryto ascertain theof thedeposits in the urea and to examine the natureof jointing in the underlying bedrock surface.2.Investigations Subsequent to BoringDuring April 1974, Eoringwas drilled to a depth of 97.8*at a iocatior, 33*(True) of the centerline of2 (see Appen-dix I for boring log) . This boring encounteredwith minorchlorite coatings a variouswith a zone of smoothcoated joints-64 to -79* elevations. These joints diptoand frequently show pyrite crystal growths over the chloritesurfaces.During 1974, four inclined borings,and 18, were down around the periphery of the Unit 2containment site to develop information relative to engineering of thecontainment Logs and orientation data for these boringsare presented in a July 31, 1974 report prepared byEngineers, Inc., Winchester, Massachusetts (see II) .Boringsandalong the west and south edges ofthe containment, respectively, encountered very few chlorite-coatedjoints.polished joint atdepth inappears likely to re-present the projection to depth of a prominent chlorite-coatedangle joint which is observed on the bedrock surface to trendthrough the centerline of Unit 2. There are no anomalouslypolished joints in BoringBoringdrilled northerly across the east edge of the con-tainment site, encountered polished chlorite-coated joints intermittentlyat depths of137* and 152-156*. Some ofthese joints appear tothe prominent east-west jointwhich trends through the centerline of Unit 2. This prominent jointappears to split into a number of high-angle branches as it passeseast into the zone of influence of Boring | |||
,and(see Figure 1) .encounteredindividual jointshavecoatings.anomalously polished orrichfound,in thedepth drilled.injoint mapping of the bed-rock surfaceBoringsanddo not indicate the presence of a through-going faultinthe area of Unit 2. These borings do appear,tothat the most prominent orchlorite-coatedjoint system in thearea trends(True) through the central part of theand dipsto the north.3. Trench ExcavationsDuring August 1974, four trenches were excavated with a back-hoe to bedrock across the 'Unit 2 site, to form anwhose legs areeach203' long and intersect at right angles at thevertical centerline of the Unit. The legs trend approximately TrueNorth,Ground surfacein the area oftrenches range fromaboutto. The elevation of the bedrock surface in the floorof the trenches rangesabout -3'Stationin the East trenchtoat Stationin the South trench. Profiles of the bedrockface along the centerlines of the trenches, as surveyed by Public ServiceCompany 'of Newpersonnel, are shown on Figuresand 3.4.Exposed in the TrenchesFigure 2 shows by half-tonethe areas of bedrock mappedby J. R. Rand in the several trenches. Although the trenches wereto bedrock, throughout, the bedrock in theelevation areastoo obscured byand mud to permit the observation of jointsor other pertinentfeatures. Although much of the bedrocksurface is rough and irregular due to glacial plucking or breaking bythe backhoe, wide areas of the bedrock are locally smooth and showglacial striations.Throughout the area exposed by the trenches the bedrock con-sists predominantly of gneissoid, sometimes quartzitic, quartz dioritewhich ranges in grain size from fine- to orientations:StrikeDipStrikeDipStrikeDipNoofof'bedrock surface or the overlyingglacialin thebreccia fab-ric,isin drill corein the Unit 2 area andthroughout thearea, can beon a smooth5'ofi nThis breccia isdips steeply, is annealedcompact,andof the glaciated bedrock surface.B. Jointingon Figure 2, jointing in the bedrock is closely spaced2 containment area,a:andat less than 3'joints (greater thandips) occur in three prominentAt the centerline of Unit 2, the most continuoustrend is This set is seen----tohavechlorite-coated surfaces. __Thejointstos e t ,thejoints arestriations whichdirections ofLow-angle joints (less thanclips) appear to be somewhat morethan high-angle joints, and occurinprominentorientations:to t'ne north.characteristic&v short__lent.StrikeStrikeStrikeand SENE andand terminate against theoccur onof p l a n a r,showstriations, with no consistent striation orientationfrom joint to joint.Fromtoin the East trench, the bedrockis subject to closely-spaced jointing, and theof the bed-rocksufficiently fractured toexcavation by t'ne backhoe.Joints in this areand smooth, and show somepolishing on conchoidal surfaces. Thin gray clay fillings occur lo-cally in discontinuous patchessome joints.showno preferredand no strike direction could be determinedfor this zone.5. Unconsolidated Glacial Deposits As shown on trench profiles on Figure 3,cobble till directly overlies the bedrock surface throughout the areaexposed by the four trenches. Tillto ground surface through-out the length of the South trench, and rises locally to ground sur-face in the North trench and in the area of the Unit 2 centerline.the till does not rise to ground surface in the trenches, theupper surface of theis a gently undulating, sub-planar erosionsurface on which a layer of medium-fine sand.At the east end of the East trench, a sequence of interbedded,layered marine clays and sands lies between the and the over-lyingsand iayer. At scattered intervals in the West, Northand East trenches, isolated boulders ranging toin diameter lieenclosed insand and rest on the upper surface of the till.Subsequent to backhoe excavation of the trenches, the contacthorizon between the till and overlyingsand was exposed andcleaned by hand throughout the length of its exposure in the West,North and East trenches. The contact was inspected and photographedby J.Rand throughout its exposed length in these trenches, andits elevation determined by transit leveling along bothof each ofthese trenches. The extent of thesand deposits in the trenchand the elevations of thecontact from place to placeare shown on Figure 2.featuresobservedthiscontact in anyof the trenches to suggest either static or dynamic deformation sub-sequent to deposition of the sand on the beveled till surface. Through-out the zone of close and slippery bedrock jointing between Stationsandin the East trench, the overlyinghorizonis sub-planar and continuous. | |||
Glacioverlying the bedrock surfacetheSouth trcrich are limited to unsorted, non-layered sand-silt-cobbletill.locallya crude stratification, and nowhereexhibit structures suggestive of podeformation.6.Examination of the overburden, bedrock surface and bedrockjoints in the Unit 2 trench excavations has revealed several distinc-tive featuresare indicative of the tectonic stability of the bed-rock at the site:A.Intermittentratified horizons in the glacial tillare not displaced over joints in the underlying bedrock.B.The undulating, sub-planar erosion surface at the top ofthe till is through-going and not subject to structural offsets or otherdeformations suggestive of faulting,C.Local exposures of glacially-scoured bedrock surfaces aresmooth across joints in the bedrock.D.Slickenside striations on closely-spaced bedrock joints ex-hibit widely divergent orientations, with no preferred attitude ororientation.John R. RandConsulting Geologist FIGURES | |||
,o7BOULDERS ON TILL SURFACEOUTiASH AND BEACH SANDE SAND.SIL1.C2EBLE TILLLT: BENCIC IN TRENCH FLOCRSURVEYED ELEV. -.3,ASE CF SANTOP OF TREHCHBATE oF TAENT8 SL),**'\letak*,5e:frock ccpbisis prederninactlyof pissoid Newburgort Vetdiorite, fine- to mediurr.graine(locally ccarse hornblende \diorite, No diabase dikes WMnoted in the trench floor.PAC URVICE COUNAY Cr KW HAIPPIli&AIWA 51A10GEOLOGIC MAP UNIT 2 TRENCHESI Ow CoduiMIMI 10 UPDATED FSARAPPENDIX 2MGEOTECHNICAL REPORTPRELIMINARY REPORT. COMPRESSION TESTS ON STRUCTURAL BACKFILL AND SAND CEMENT,STATIONThe information contained in this appendix was not revised, but has beenextracted from the originaland is provided for historical information. | |||
PRELIMINARY REPORT'COMPRESSION TESTS ONSTRUCTURAL BACKFILL AND SAND-CEMENTSTATIONJanuary 24, 1978Prepared forPUBLIC SERVICE CO. OF NEW HAMPSHIREandUNITED ENGINEERS AND CONSTRUCTORS, INC.Geotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890Project 77386 1.INTRODUCTION1.1 Purpose1.2 Scope1.3 ScheduleTABLE OF CONTENTSLIST OF TABLESLIST OF FIGURES2.DESCRIPTION OF STRUCTURAL BACKFILL ANDRESULTS OF INDEX TESTS2.1 Description2.2 Grain-Size Distribution Tests2.2.1 Procedure2.2.2 Results2.3 Specific Gravity Test2.3.1 Procedure.2.3.2 Results3.MOISTURE-DENSITY RELATION TEST4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTS4.1 Procedure4.2 Stress-Strain Curves For S Tests4.3 Moduli and Poisson's Ratios For S Tests5.1 Procedure5.2 Stress-Strain Curves ForTests5.3 Moduli and Poisson's Ratio ForTests6.TESTS ON SAND-CEMENT7.COEFFICIENT OFREACTION7.1 Structural BackfillNOTATIONSTABLESFIGURESAPPENDIX ASTRESS-STRAIN CURVES FOR DRAINED TESTSAPPENDIX BSTRESS-STRAIN CURVES FOR UNDRAINED TESTSPage No.243.1 Procedure3.2 Results5. CONSOLIDATED-UNDRAINED,TRIAXIAL TESTS910101344 LIST OF TABLESTable 1Schedule of Tests on Sand-CementTable 2Consolidated-DrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 3Consolidated-UndrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 4Unconfined Tests on 2-in. Cube Samplesof Sand-Cement, 5% Cement .TableCompression Tests on 2.8-in.-diameterSamples of Sand-Cement, 5% Cement.*To be added when tests are complete. 2. DESCRIPTION OF STRUCTURAL BACKFILLAND RESULTS OF INDEX TESTS2.1 Description Beard Pit No. 5 soil is a yellowish-browngravelly sand containing about two percent fines.2.2 Grain-Size Distribution Tests Two sieve analyses were performed.The grain-size dis-tribution of Beard Pit No. 5 soil as received was first, determined. The entire sample wassieved on aNO. 4 (4.75 mm) mesh and a grain-size distribution of soilpassing the No. 4 mesh was determined.The minus No. 4 mat-erial was used for triaxial testing.2.2.1 ProcedureTo determine the grain-size distribution ofthe original soil, a representative samplewas selected, weighed and air-dried.Thesample was sieved on a mesh and ag-gregates retained were removed, weighed andseparately sieved. A representative sampleof aggregates passing the mesh wasweighed, oven-dried and washed on a No. 200mm) sieve.The soil retained on theNo. 200 sieve was oven-dried, weighed andmechanically sieved.The entire quantity of soil was then sievedon a No. 4 (4.75 mm) mesh and aggregates re-tained were removed. A representative sampleof soil passing the No. 4 mesh was oven-driedand washed on a No. 200mm) sieve.Soilretained on the No. 200 sieve was subsequentlyoven-dried, weighed and mechanically sieved todetermine the grain-size distribution of thesoil to be used for compaction and triaxialtesting.2.2.2 ResultsThe grain-size distribution curve of BeardPit No. 5 soil is presented in Fig. 1.The grain-size distribution curve of the soilpassing the No. 4 (4.75 mm) sieve is presentedin Fig. 2. 4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTSSix S tests were performed on compacted specimens ofBeard Pit No. 5 soil.Only soil passing a No. 4 sieve wasused.Specimens were compacted to 90% and 95% of the maxi-mum dry unit weight as determined by ASTM Designation D1557,Method A (Section 3).Tests were performed at effectiveconsolidation pressures of 0.5, 2.0 and 6.0 ksc (7.1, 28.4,85.3 psi).Test specimens typically had a diameter ofand a height of 6.6-in.4.1 ProcedureA predetermined quantity of air-dried soil was thoroughlymixed with distilled water to a water content of 14%.Themixture was divided in seven portions of equal weight andplaced in covered containers.The compaction was performed in seven layers within asplit mold. The mold was lined with a rubber membrane whichwas held tightly to the inside of the mold by a small vacuum.The first soil layer was placed in the mold and leveled off.A l-psi surcharge was lowered onto the soil and vibratedvertically using an Ingersoll-Rand pneumatic hammer.Thehammer provided low frequency-high amplitude vibrations.Thelayer was compacted to a predetermined height to achieve thedesired unit weight.The surcharge was removed and the soilsurface scarified. Subsequent layers were added and compactedin the same manner to form a test specimen of the desired sizeand unit weight.The mold and specimen assembly was then mounted on thebottom platen of a triaxial cell. A vacuum of approximatelyof Hg was applied to the specimen to provide support tothe specimen. The mold was removed and the diameter and heightof the specimen were measured. A second membrane was placedaround the specimen and O-rings attached to seal the membranesto the top and bottom platens.The triaxial cell was subsequently assembled and floodedwith water. A chamber pressure of 0.5 ksc was applied and thevacuum released to distilled water at atmospheric pressure.When the vacuum had dissipated, distilled water was permeatedthrough the specimen to improve saturation by displacing airvoids. A back pressure of approximately 10 ksc was utilized tocomplete saturation.B-values of 0.90 or higher were measured. | |||
..a.normalized shear stress on theplane,vs. axial strain, andThe specimen was then consolidated to the desired effectiveconsolidation pressure. Volume changes during consolidationwere measured by monitoring the flow of pore water throughthe drainage system.The test specimen was subsequently loaded axially at aconstant rate of strain of approximatelyDuringshear the specimen was allowed to drain through both ends.Volume changes were measured by monitoring the flow of porewater. Axial loads were measured with a proving ring anddeformations were monitored with an axial dial.The testwas terminated at 20% axial strain.The specimen was thenremoved and oven-dried to determine the weight of solids.4.2 Stress-Strain Curves For S Tests Results of the consolidated-drained triaxial, S, testsare plotted in terms ofb. volumetric strain,VS. axial strain.The results of individual S tests are presented in Appen-dix A and Table 2 contains the details of each S test performed.A summary of S tests performed on specimens initially com-pacted to a specific 90% compaction are plotted in Fig. 4, and95% compaction in Fig. 5.4.3and Poisson's Ratios For S TestsFigs. 6 and 7 are plots of secant modulus and Poisson'sratio, respectively, as a function of axial strain from thetriaxial S tests.Fig. 8 (top) is a plot of the initial tangent modulus andthe secant modulus at 50 of the compressive strength versusthe effective consolidation pressure,At the bottom inFig. 8 is a similar plot for the values of Poisson's ratios. 6. TESTS ON SAND-CEMENTWe herewith forward results of tests on 2-in. cubespecimens of sand-cement, so that thewill be avail-able early in this preliminary form.In Fig. 13 are plotted the stress-strain curves for un-confined tests on three replicate specimens cured for 7 days,and in Fig. 14 are the stress-strain curves for unconfinedtests on three replicate specimens cured for 28 days. De-tails of these tests are given in Table 4.The sand-cement specimens were prepared using the samesand and cement that were used at thesite for testbatches.The mixtures are shown in Figs. 13'and 14.It may be seen that the strength increased rapidly withcure time. A strength increase that is logarithmic with timewould lead to the predition of an average strength of 180psi for the specimens curedmodulus would increase to 33,800 psi.Similarly, the average | |||
: 7. COEFFICIENT OFREACTION7.1 Structural BackfillTo determine reasonable values for the coefficient ofreaction of buried pipes, the following proceduremay be used:1.Determine whether the loading condition is"drained" or "undrained." That is, will volumechanges take place during loading (drained), orwill volume changes not occur during loading(undrained) .2.Establish the allowable diametral strain ofthe pipe. That is, select a diameter-strainthat the pipe can withstand with an adequatefactor of safety. That strain may be as lowas 0.1% for stiff, brittle pipes,to 3% or 4%for flexible pipes.3.Compute the vertical effective stress in theground at the level of the middle (springline)of the pipe.4.Choose whether the expected degree of compactionof the structural backfill is 90% Modified or95% Modified.5.Given the above data, enter the appropriatetable below, and interpolate to obtain a valueofi.e., the coefficient oftimes the pipe diameter (in psi).6.Divideby the pipe diameter to obtain thevalue ofin pci (pounds/cubic inch). | |||
TABLE 2CONSOLIDATED-DRAINEDTRIAKIAL TESTSSTRUCTURAL BACKFILLBEARD PIT 5 SANDSTATIONPercent Compaction, PEffectiveBAt Max. Compressive StressModuli ASTM D1557, AConsoli-ValueDeviator AxialVolumeInitial At 50%InIn Triaxial CelldationStressStrain StrainCompac-InitialAftertionConsoli-MolddationMax.Stress0Stresspcf--13.8100.7s213.8100.9s313.8101.0s413.8106.413.5106.3S613.7106.3GeotechnicalEngineersInc.Project 7738623, 1978pcfksckscpsip si100.8100.889.990.090.00.500.971.641.310.416,2604,0500.310.43101.0101.590.190.290.62.000.955.882.380.0814,22011,0900.170.23101.3102.390.290.491.46.000.9515.057.28-0.6623,75018,7700.220.23106.4106.495.095.095.00.500.952.341.310.9213,5109, 6000.330.35106.4106.894.995.095.32.000.977.960.9221,33016,1400.170.27106.4107.394.995.095.86.000.9519.354.000.3429,15024,7400.200.27Test InitialDry Unit WeightsNo.WaterInIn Triaxial CellContentInitialAfterConsoli-MolddationPoisson's RatioInitial At 50%Stress3ca STATIONSTRUCTURAL BACKFILLBEARD PIT 5 SANDEffectiveASTMA Consoli-Value Deviator AxialEffectiveInitialAt 50%InIn Triaxial CelldationMinorCompac- InitialStressPrincipaltionConsoli-StressMolddationTest InitialDry Unit WeightsPercent Compaction, P13.7101.0101.2101.290.290.490.40.500.966.869.532.635,8303,13013.5100.6100.6100.989.889.890.12.000.907.948.333.1112,7305,760ii313.8100.8101.1102.290.090.391.26.000.9911.326.69.4.4638,11018,63013.6101.0101.2102.390.290.491.36.000.9512.245.734.7724.46019,05013.8106.3106.5106.594.995.195.10.500.9519.9113.837.2311,8707,180ii513.6106.3106.3106.694.994.995.22.000.9521.8714.537.9319,7708,39013.5106.3106.4107.294.995.095.76.000.9627.8811.58io.3544,01014,220GeotechnicalEngineersInc.Project77386January 23,1978p pcf cfpcf- ksc -ksckscpsiCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSNo.WaterInIn Triaxial CellContent Compac- Initial AfterConsoli-MolddationBAt Maximum Compressive UnitWeightWetUnconfinedStrengthpsiStrainModulusAtofPeakElasticity*psiCureTimedaysTestNo.TABLE 4UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5% CEMENTSTATION77-1124.066.70.8010,600123.972.50.9210,110126.285.30.8313,650Avg 74.82828-1127.4141.60.67126.2133.80.77126.8130.00.87Avg 135.0Avg 11,45033,33019,13022,760Avg 25,0709090-290-3*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386.January 23, 1978 FIGURES Lab. 4-3 rev. 0U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER50050IOI0.5GRAIN SIZE MILLIMETERSCOBBLESSANDCOARSEFINECOARSEMEDIUMIFINEIIGRAIN-SIZEDISTRIBUTIONTriaxialTestsBEARD PIT NO. 5SOILStructuralBackfillProject77386Jan.23,1978Fig.1New HampshirePublic Service Company ofEngineers Inc.Winchester,Massachusetts Lab. 4 - 3 rev. 028 May 74500100505I0.50.10.05GRAIN SIZE MILLIMETERSISILT OR CL AYCOARSEFINECOARSEMEDIUMIProject 77306Jan. 23, 1978Fig. 2II\-10go-20I-IIIIIIIIIIIIIIIIIJ - 7 0809020IO0IIIIIU.S. STANDARO SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER64 3I1420 30 40 50 70200II*IIIIIIIIIIIIIII\IIIIIIITriaxial TestsStructuralBackfillGRAIN-SIZE DISTRIBUTIONBEARD PIT NO. 5 SANDNO. 4 MATERIALPublic Service Company ofNew HampshireGeotechnical Engineers Inc. .Winchester, Massachusetts WATER CONTENT,As mixed before compaction0 After compaction1051 1 31 1 11 0 91 0 704122 024TESTSSTRUCTURAL BACKFILLMOISTUREDENSITYRELATION TESTBEARD PIT No.5 SOILJanuary1978 Fig. 3PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386ENGINEERS INC.WINCHESTER,MASSACHUSETTS PROJECT 77366DECEMBER, 1977 FIG. 43024681416182006.0AXIAL STRAIN, %ENGINEERS INC.VI NCH ESTER, M ASSACHUS ETTS 2.51.5.1.0TESTs40.5s52.0S66.006420-2024681416 1820AXIAL STRAIN,%TRIAXIAL TESTSSERVICE COMPANYOF NEW HAM SSV IR^EUC T U R A L B A C K F I L LDECEMBER, 1977 FIG. 5PROJECT 77386ISUMMARY OFDRAINED TRIAXIAL TESTSCOMPACTIONENGINEERS INC AXIAL STRAIN,F O RW0III30,0002 5,00020,00090% Modified Compaction10,000.IIIII00.40.60.81.01.21.42.0IIIW000.40.60.81.21.41.61.82.0IIIII95Compact ionIPUBLIC SERVICE gCOMPANYOF NEW TARPUSHfI2RET U R ENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386JANUARYTESTSA LB A C K F I L LDRAINED LOADING 1.61.82.000.20.40.60.81.01.21.4AXIAL STRAIN,TESTS90% Modified Compaction7.1psi0.20.40.60.81.01.21.41.62.0III95% Modified Compactionpsi .PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386JANUARYFig. 7,ENGINEERS INC.MASSACHUSETTS1.21 .o0.80.60.40.201.2.o0.80.60.40.20STRUCTURAL BACKFILLPOISSONS RATIOSFOR DRAINED LOADING 10020300E moduluscompactionEmodulus50%peakcompactionE modulus95% compactionE modulus atpeokcompaction95% compactionvat 50%peak95%90% compactionat 5 00.50.40.30.20.10kg(Multiply by 14.22 for psi)SERVICE COMPANYqF NEI HAMPSHIRECENGINEERS INC.YINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSUMMARY OFFSTRUCTURALILLDRAINEDTESTSPROJECT 77386FIG. 8 4678910TEST NO.0.502.0002468141618206.006.00AXIAL STRAIN , %SERVICE COMPANYSUMMARY OFTRIAXIAL TESTSOF NEW H'WWHIJRCET UR A LB A C K F I L LUNDRAINED TRIAXIAL TESTS90% COMPACTIONENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. 9 TEST NO.*3c kg/cm2kg/cm2R40.50R52.00R66.0006421214R6STRESS-STRAINR63024681012141618 20AXIAL STRAIN,%PUBLIC SERVICE COMPANYOF NEW HAMPSHIREGEOTECHNICAL ENGINEERS INC.WINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSTRUCTURAL BACK FILLPROJECT 77386SUMMARY OF CONSOLIDATED-UNDRAINED TRIAXIAL TESTS95% COMPACTIONDECEMBER,1977 FIG. 10 SECANT MODULUS,psiundrained loadingSECANT MODULUS, Es, , psiundrained loading0DXriI I.II ENGINEERS INC.*WINCHESTER, MASSACHUSETTSPROJECT 77386DECEM 8FIG.(Multiply by 14.22 for psi)00 90% Compact ion90% CompactionCompaction 95% CompactionNOTE POISSONS RATIO FOR UNDRAINEDTESTS MAY BE TAKEN AS 0.49 TO 0.50 | |||
,12080400I2345AXIAL STRAINSand-Cement Mixture (by weight):1 part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimens7 daysUnit weight after cure7-1 124.07-2 123.97-3 126.2Strain control. loading at 1.5 mm/minPublicCompanyof New HampshireEngineers Inc.Winchester,MassachusettsCOMPRESSION TESTS7-DAY CURE5% CEMENTJanuary 1978Fig. 13Triaxial TestsStationSand-CementBackfillProject 77386 | |||
.,AXIAL STRAINSand-Cement Mixture (by weight):1part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimensCured 28 daysUnit weight after cure28-1 127.428-2 126.228-3 126.8Strain control loading at 1.5Public Service Companyof New HampshireTriaxial TestsCOMPRESSION TESTSSand-CementBackfill28-DAY CURBStation5% CEMENTGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386January 1978Fig. 14.. | |||
APPENDIX A SERVICE COMPANYPROJECT 77386ENGINEERS INC.10121618201.0VOLUMESTRESS STRAINAXIAL STRAIN,%TEST90% CompactionTRIAXIAL TESTSITRAL BACK F I L LCONSOLIDATED-DRAINEDTRIAXIAL TESTDECEMBER, 1977 FIG.OF NEW HAMVTHIRITC T 2.50.5STRESS STRAIN002468101214161820AXIAL STRAIN,%TEST S290% Compaction= 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF ^EW RHAUMPCS4IR15 R A LB A C K F I L LGEOTECHNICAL ENGINEERS INC.PROJECT 77386DECEMBER, 1977 FIG. A21.50-0.5VOLUME STRAINCONSOLIDATED-DRAINEDTRIAXIAL TEST S2 2.5STRESS-1.5,VOLUME-2.0.02468101214161820AL STRAIN,%TEST S3 90Compaction3c = 6.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386DECEMBER, 1977 2.51.51.00.5064202VOLUME STRAIN681012141618AXIAL STRAIN,%TEST S495% Compaction3c = 0.5T R I A X I A L^aSERVICE COMPANYICONSOLIDATED-DRAINEDOF NEW HAMPSHIRESTRUCTURAL BACKFILLPROJECT 77386GEOTECHNICAL ENGINEERS INC .YINCHESTER,MASSACHUSETTSDECEMBER, 1977 1.5.1.00.5 . .STRESS0VOLUME STRAIN2461012141620AXIAL STRAIN,%TEST95% Compaction2.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETEST,STRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386 DECEMBER, 6PROJECT 77386I DECEMBER, 1977 FIG. A2.5STRESS STRAIN-1.024681012741618 20VOLUME STRAINAXIAL STRAIN,%TEST S695% Compaction= 6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,SEOTECHNICAL ENGINEERS INC.1TRIAXIAL TESTSSTR UCTURAL BACKLL 4.03.02.0I>3=1.64E6260 psi4050 psi.1.00.60.40.200.40.81.21.6AXIAL STRAIN,%TEST90% Compaction= 0.5CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPROJECT 77386DECEMBER,1977 FIG. A7ENGINEERS INC.MASSACHUSETTSSERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILL 8.0= 5.883E014220 psi11090 psi6.04.0I2.00-0.1-0.2-0.3-0.400.81.21.62.0AXIAL STRAIN,%TEST S290% Compaction= 2.0SERVICE COMPANYOF NEW HAMPSHIRET R I A X I A L TESTSSTRUCTURAL BACKFILLENGINEERS INC.VVINCHESTER, MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S2Expanded ScalesPROJECT 77386DECEMBER,!977 FIG. | |||
AXIAL STRAINTEST S390% Compaction6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,STRUCTURAL BACKFILLPROJECT 77386TESTSTEST S3Expanded ScalesENGINEERS INC.WINCHESTER, MASSACHUSETTS 3= 2.34E013510 psiE9600 psi= 0.3350= 0.3500.40.81.2162.0AXIAL STRAINTEST S495% Compaction= 0.5SERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILLENGINEERS INC.MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S4Expanded ScalesPROJECT 77386IFIG. | |||
TEST95% Compaction3c = 2.0TESTSSKTRUCFTURALILLPROJECT 77386CONSOLIDATED-DRAINEDTRIAXIAL TEST S5Expanded ScalesF I G .SERVICE COMPANYOF NEW HBAMPSAHIRECMASSACHUSETTSENGINEERS INC.-0.20.40.2AXIAL STRAIN,%32133016140=7.96kg/cm-psipsi8.062.I4. | |||
I-0.1-0.3,1 6 . 012.04.08.0 .AXIAL STRAINTEST95% Compaction= 6.0PROJECT 77386DECEMBER,1977 FIG.CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.NINCHESTER, MASSACHUSETTSTESTSSTRUCTURAL BACKFILL APPENDIX 246814161820AXIAL STRAIN , %-SSPA81012141618TEST90%Compactiona3c1412108606PUBLIC SERVICE COMPANYOF NEW HAMPSHIRESTRUCTURALTRIAXIALPROJECTTESTSBACKFILL77386IDECEMBER,1977CONSOLIDATED-UNDRAINEDTRIAXIAL TEST 3.53.02.51.5STRESS PA0.5TEST90% Compactiona 3c002468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSOFSHf %P ^ H^R f U RTRIAXIAL TESTA LB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. B2 1.25"1.0DO.750.25STRESS-S TRAINSPA01.00.500.751.001.251.501.752.002.252.TEST90% Compaction6.0.. 2524681214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYOF NEW HOMPSMIRE CPROJECT 77386DECEMBER, 1977 FIG.T R I A X I A L TESTSSTKRUCTFURALILLCONSOLIDATED-UIJDRAINEDTRIAXIAL TESTENGINEERS INC.WINCHESTER, MASSACHUSETTS STRESS PASTRESS0.250.500.751.001.251.501.752.002.25TESTCompaction3c6.002468101214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIALTESTSOF NEW HAMPSHIRETRIAXIAL TESTBACKFILLSTRUCTURAL,ENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG. B4PROJECT 77386 s TRESS PASTRESS-S05101520253035404550TEST90% Compactiona 3c0024681012 14 1618 20AXIAL STRAIN, %PUBLIC SERVICE COMPANYTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDO F N E ^l 0 ALY PCS1^I RUE R ATRIAXIAL TESTLB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER, 1977 FIG. B5 S ESS PA-S10121416TEST90% Compactiona 3c= 2.02468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYTRIAXIAL TESTSOS TF RNEU CHATP UHIRREA LTRIAXIAL TESTB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG.PROJECT 77386 0.502468lo14161820AXIAL STRAIN ,ENGINEERS INC..WINCHESTER,MASSACHUSETTS00.51.01.52.02.53.03.54.04.55.PROJECT 77386TEST90% Compaction6.0DECEMBER, 1977 FIG. BSTRESS PA TRIAXIAL TESTSSTRUCTURAL BACKFILLPROJECT 773860.40 . 81.21.6AXIAL STRAIN,4.01.03 . 020TEST90% Compaction= 0.53cCONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.WINCHESTER, MASSACHUSETTS 4.03.0bI20.1.0AXIAL STRAIN, %TEST90% Compactiona 3c = 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESENGINEERS INC.WINCHESTER, MASSACHUSETTS1PROJECT 77386DECEMBER,1977 CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER,19778.00.40.81.2AXIAL STRAIN,.%TEST90% Compaction ,6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREE N G I NWINCHESTER, MASSACHUSETTST R I A X I A L TESTSSTRUCTURAL BACKFILLE E R SI N C;PROJECT 77386 AXIAL STRAIN,ENGINEERS INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG00.40.81.21.68.0TEST90% Compaction= 6.0.6.03c PUBLIC SERVICE COMPANYOF NEW HAMPSHIRECONSOLIDATED-UNDRAINEDT R I A X I A L TESTSTRTAXTALISTRUCTURAL BACKFILLSCALESTEGEOTECHNICALCHNICA L ENGIENGINERSNEER SINC.INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977AXIAL STRAIN,8.02.0TEST90% Compaction.3c= 0.5 00.40.81.21.62.0AXIAL STRAIN,20164I12TEST90% Compaction3 c = 2.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERSWINCHESTER, MASSACHUSETTSTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESPROJECT 77386IDECEMBER, 1977 AXIAL STRAIN,20.016.04.012.08.000.81.21.62.0TEST90% Compaction= 6.0 kg/cm.CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER, 19773c ENGINEERS INC.1017 MAIN STREETWINCHESTERMASSACHUSETTS 01890729-1625February 14, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th FloorManchester, NH 03105 | |||
==Subject:== | |||
Interim Test Results on Sand-Cement BackfillStation | |||
==Reference:== | |||
Preliminary Report, Compression Tests onStructural Backfill and Sand-CementStation,January 24, 1978 | |||
==Dear Mr.The purpose of this letter is to present data on moduli deter-mined on sand-cement backfill at the request of United Engineersand Constructors Inc. The data herein supplements the data in thereference and will be incorporated in the completed version of thatreport.Themodulus values were submitted to Mr. Pate1ofby telephone on February 13,== | |||
1978.The stress strain curves for three unconfined compression testson cylindrical specimens are shown in the enclosed Fig. 15 and thetest data are summarized in the enclosed Table 5.The following values of the coefficient ofreactionwere computed for the cube and cylindrical specimens cured for 28days.. | |||
Mr. JohnFebruary 14, 1978FOR SAND-CEMENT BACKFILL28-DAY CURETabulated values are in psiEffectiveVerticalStress atAllowable Diameter Strain, Springline0.020.10.30.5CUBE SPECIMENS100,000CYLINDRICALSPECIMENS200,00089,00060,00036,000The stress strain curves for the cylindrical specimens show aninitial straight line portion withhigh modulus of elasticity.At axial strains of about 0.03% there is a break in the curves and asecond straight line is followed up to near the peak strength.Thetangent modulus of this second straight line portion of the curves isabout one-third of the initial modulus.Fig. 16 shows the variation ofthe secant modulus with axial strain for the unconfined tests on cylin-drical specimens.Seating problems occurred in the tests on the cube specimens, asseen in Figs. 13 and 14 of the above reference, and thus the high initialmodulus observed for the cylindrical samples was not observed for thecubes. However, the second straight line slope for the cylindricalspecimens in Fig. 15 is in good agreement with the straight line portionof the curves for the cube specimens.The compressive strength of thecube specimens is somewhat higher than that of the cylindrical specimens,probably as a result of the more significant end restraint of the cubespecimens.For these two reasons we feel that the results of tests oncubes and cylinders are consistent with each other, but that the resultsfor tests on cylinders are more reliable and should be used to establishmoduli ofreaction. | |||
Mr. JohnFebruary 14, 1978We have also provided by telephone various friction coefficientsand estimates of shear wave velocities in the compacted soil. Thesedata will be confirmed in writing at a later date.Sincerely yours,Steve J. PoulosPrincipalEncl.cc:R.YAEC w/l encl.D.w/l encl.A. Desai,w/l encl. | |||
ConfiningCompressiveStrainInitialStressStrengthAtModulus ofPeakElasticitykscpsi%psiCureTestUnitTimeNo.WeightWetdaysTABLE 5 COMPRESSION TESTS ON 2.8-IN.-DIAMETER.SAND-CEMENT SPECIMENS, 5% CEMENTSTATION2828-O-l126.20.002828-O-2124.80.002828-O-3124.10.0091.00.6588.8.0.58106.10.8075,00052,20034,30095.3Avg 50,500Geotechnical Engineers Inc.Project 77386February 7, 1978 StationTriaxial TestsProject 77386February 1978Fig. 15Engineers Inc.Winchester, MassachusettsPublic Service Company ofSand-CementBackfillSpecimens Tested:specimens28-day cureUnconfined testsStrain control loading at1.10.81.6AXIAL STRAIN ,Sand-Cement Mixture:Xa1part cement16.18 parts sand (oven-dry)2.79 parts waterCOMPRESSION TESTS2.8-IN.-DIAMETER SPECIMEN5% CEMENT, 28-DAY CURE Winchester, MassachusettsProject 77386600 .00.20.40.81.01.2STRAIN AT PEAKAVERAGE= ksAXIAL STRAIN,,Triaxial TestsSand-CementBackfillStationPublic Service Company ofNew HampshireGeotechnical Engineers Inc.February 197816SECANT MODULUS VS STRAINSPECIMENS5% CEMENT,CURE 203060500AXIAL STRAIN,, %0.20.4= | |||
ENGINEERS INC.1017 MAIN STREET. WINCHESTERMASSACHUSETTS 01890Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street-11th floor..Manchester, NH 03105 | |||
==Subject:== | |||
Interim Test Results on Sand-Cement'BackfillStation | |||
==Reference:== | |||
Preliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978Bear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letter of February 14.These triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 33 days instead ofthe intended 28 days because of the February 6, 1978 blizzard herein Boston. The test data are summarized in a revised Table 5 andthe stress strain curves are presented in Fig. 17.The modulus and strength data were estimated for 28-day curingon the basis of the rate of change of modulus and strength withtime as measured using the cube specimens (see referenced report).The estimated values of strength and modulus for 28-day cure alsoare shown in Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letter of February14. The following table lists all values obtained to date for thesand-cement specimens. | |||
FOR SAND-CEMENT BACKFILLCURE, 5% CEMENTGEOTECHNICALINC.cc:R. Pizzuti, YAEC w/l encl.w/l encl.A. Desai,w/l encl.D.. Patel,w/l encl.Mr. JohnFebruary 27, 1978Tabulated values are in psiEffectiveAllowable Diameter Strain, %VerticalStressatSpringlinepsi0.10.30.5.CUBESPECIMENS0100,000.CYLINDRICALSPECIMENS0200,00089,00060,00036,00042.7138,000163,000129,600Sincerely yours,Steve J. PoulosPrincipalGC:msEncl. | |||
TABLE 5COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%STATION372.3652.1035,00033,6003762.4033,30036931,7003641.4040,00035738,40042.742.7124.8332833283328EstimatedTestNo.days28-O-lUnitWeightWetConfiningCompressiveStrengthpsiStrainInitialatModulus ofPeakElasticitypsi126.20.00910.6575,0002828-O-2124.80.00890.5852,200.2828-O-3124.10.001060.8034,300NOTE: 1) The percentage of cement is computed as the ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.2) The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.Geotechnical Engineers Inc.Project 77386February 7, 1978Revised February 24, 1978 3= 42.7 psi0.8 IIII 0051.0I.52.02.53.03.54 . 0AXIAL STRAIN, %Project 77386Feb. 23, 1978Fig.17StructuralBackfillTriaxial Tests2.8-IN.-DIA., 5% CEMENT33-DAY CURE,=SAND-CEMENT SPECIMENSPublic Service Company ofNew HampshireEngineersWinchester,Massachusetts 1017 MAIN STREET. WINCHESTER. MASSACHUSETTS 01890729-1625March 10, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire.1000 Elm Street11th FloorManchester, NH 03105Interim Test Results on Sand-Cement Backf illStationPreliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978 | |||
==Dear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letters of February 14 and27.Three triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 28 days and weretested under a confining stress of 7.1 psi.The test data aresummarized in a revised Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letters of February14 and 27. The following table lists all values obtained to datefor the sand-cement specimens:== | |||
Mr. JohnMarch 10, 1978FOR SAND-CEMENT BACKFILL28-DAY CURE, 5% CEMENTTabulated values are in psiEffectiveVerticalAllowable Diameter Strain, Stress atSpringlinepsi0.10.30.5CUBE SPECIMENS01 0 0, 0 0 0CYLINDRICAL SPECIMENS0200,00089,00060,0007.1115,000106,00079,60042.7138,000163,000129,600*Modulus value determined at strains greater than the strain at peakcompressivestrength.Geotechnical Engineers Inc.Project 77386Revised March 6, 1978 Mr. JohnMarch 10, 1978,GEOTECHNICALINC.GC/SJP:msEncl.cc: R. Pizzuti, YAECD.A. Desai,D. Patel,Three unconfined tests were performed on cube specimens ofsand-cement cured for 90 days. The test data are summarized ina revised Table 4.The stress-strain curves for the additional tests will betransmitted as soon as they have been drafted.Sincerely yours,Steve J. PoulosPrincipal UnitWeightWetCureTimedaysTestNo.TABLE 4 UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5 % CEMENTSTATIONUnconfinedStrengthpsiStrainModulusAto fPeakElasticity*%psi28907-l124.07-2123.97-3126.228-l127.428-2126.228-3126.890-l124.490-2124.590-30.8010,6000.9210,1100.8313,650Avg 11,450141.60.67.33,3300.7719,1300.8722,760 Avg 135.00.951.080.84Avg 28,200Avg 25,07026,32027,03031,250*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386January 23, 1978Revised6, 1978 126.2124.8124.175,00052,20034,3002828-O-l2828-O-22828-O-30.0910.650.0890.580.0.1060.80TABLE 5--COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%CureTimeNo.daysUnitWeightWetConfiningCompressiveStrengthpsiStrain.InitialatModulus ofPeakElasticitypsi283333283342.742.7423722.1035,00028282 8281)372.3762.4033,3001.4040,00039,6007.11197.1134124.3The percentage ofthe ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.34,60037632,9003643640.6032,6000.9022,9000.9717,400Geotechnical Engineers Inc.Project 77386February1978Revised-February 24, 1978Revised March 6, 1978 UPDATED FSARAPPENDIX 2NGEOTECHNICAL REPORT TEST FILL STUDY OF QUARTZITE MOLE CUTTINGS The information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
William R.Senior EngineerStevePrincipalTEST FILL STUDYOFQUARTZITE MOLECUTTINGSSubmitted toPublic Service Company of New HampshireSubmitted byGeotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890July 13, 1979Project 76301 81010101111111314TABLE OF CONTENTSPage No.LIST OF TABLESLIST OF FIGURES1.INTRODUCTION1.1 Purpose1.2 Background1.3 Summary2.CONSTRUCTION OF TEST FILLS2.1 Gravelly Sand2.2 Molecuttings (Controlled Placement)2.3 Molecuttings (No Special Controls)2.4 Stratified Molecuttings and Gravelly Sand3.PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand3.2 Molecuttings (Controlled Placement)3.3 Molecuttings (No Special Controls)3.4 Stratified Molecuttings and Gravelly Sand4.PLATE LOAD TESTS5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS5.1 Grain-Size Limits5.2 Lift Thickness5.3 Determination of In-Place Dry.Density5.3.1 Gravelly Sand5.3.2Molecuttings5.4 Determination of Percent Compaction5.5 Water Content ControlTABLESFIGURESAPPENDIX ARECOMMENDEDFOR PLACEMENTAND FIELD CONTROL OF MOLECUTTINGSAPPENDIX BPLATE LOAD TESTS LIST OF TABLESTable 1Summary of Field Density TestsGravelly Sand Test FillTable 2Summary of Field Density TestsMolecuttings (Controlled Placement) Test FillTable 3Summary of Field Density TestsMolecuttings (No Special Controls) Test FillTable 4Summary of Field Density TestsStratified Molecuttings and Gravelly Sand Test FillTable 5Summary of Plate Load Tests Results LIST OF FIGURESFig. 1Plan View of Test FillsFig. 2Profile of Test FillsFig. 3Profile of Test FillsFig. 4Compaction CurvesGravelly SandFig. 5Grain Size CurvesGravelly Sand Test FillFig. 6Compaction CurvesMolecuttings.Fig. 7Grain Size CurvesSamples of MolecuttingsFig. 8Modulus of Elasticity vs Percent CompactionMolecuttings.Fig. 9Water Content Sand ConeNuclear Density MeterGravelly SandFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryGravelly SandFig.Water Content Sand Cone vs Nuclear Density MeterDet., MolecuttingsFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryMolecuttings the same percent compaction.problem was addressed byInvestigation of the resistivityINTRODUCTION1.1 Purpose The intake and discharge tunnels atStation arebeing excavated using a tunnel boring machine, more commonlytermed a mole. The excavated material from the mole is awidely-graded crushed stone commonly termed tunnel muck, which,for this report, shall be termed "molecuttings."The purpose of the test fill study was to determine if thequartzite molecuttings obtained from-the tunnel excavationscould be used for Safety and Nonsafety-Related Structural Fill.Construction of the test fills provided the opportunity to ob-serve the behavior of the molecuttings during placement andobtain data necessary to develop procedures to control the com-paction of the molecuttings during placement.1.2 Background The molecuttings from the quartzite bedrock in the tunnelsare widely-graded crushed stone containing up to 13% passingthe No. 200 sieve.The grain size curve of the molecuttingsplots below the lower limit of the Safety and Nonsafety-RelatedStructural Backfill specification.The resistivity of thecuttings is generally below the specified minimum value of10,000Thus, although the molecuttings appearedsuperior to the gravelly sand structural fill as a backfillmaterial, it was rejected because the gradation and resistivityrequirements did not comply with the specifications.Useofthe molecuttings for Safety and Nonsafety-Related StructuralFill required that selected tests be performed which would demon-strate that the molecuttings were as good or better than thepresently used gravelly sand when both materials were placed atThe Safety and Nonsafety-Related Structural Fill is usedfor backfill around pipes and conduits, under floor slabs, roads,etc.For these applications the deformation characteristics ofthe backfill will control the soil support of the pipes andsettlements of structures. One method of determining the defor-mation properties of a soil is by determining the soil modulusby the use of a plate load test.Plate load tests were performedon carefully constructed test fills consisting of (a) gravellysand, (b) molecuttings, anda test fill of essentially alter-nating layers of gravelly sand and molecuttings which herein willbe referred to as the stratified gravelly sand and molecuttings test fill The modulus from each test fill was used as a means of comparingthe desirability of the molecuttings versus the gravelly sand foruse as Safety and Nonsafety-Related Backfill.The molecuttings are widely graded and containhigh percentages of stone retained on thesieve.In manycases the percentretained on thesieve exceeds theallowable limits for the Modified AASHO compaction testThus, it was necessary to determine by means of field and labora-tory tests performed during construction of the test fill howconstruction control of the placement of the molecuttings shouldbe handled.., 1.3 Summary The results of the plate load tests indicate that thecuttings will provide superior support for pipes and structuresthan the gravelly sand currently accepted for Safety andsafety-Related Structural Fill when both materials are placed atthe same percent compaction.The molecuttings and gravelly sandwill provide about equivalent deformation properties when thepercent compaction of the molecuttings is as much as 2 to 3%lower than the gravelly sand.Therefore, the use of molecuttingsfor Safety and Nonsafety-Related Structural Fill is recommended.Further, it is recommended that the percent compaction of themolecuttings for Safety and Nonsafety-Related Structural Fill be95% andrespectively.The molecuttings used in constructing these test fills werewidely graded crushed stone with up to 7% passing the No. 200sieve.The water content of the material varied from 3 to 4% upto 10% during placement.Because of the grain-size distributioncompaction of the molecuttings was sensitive to fluctuations inthe water content of the material. Based on data obtained fromtests performed during construction of the test fills, limitationson the grain-size distribution and water content'of thecuttings during placement have been recommended in Section 5.Construction of the test fills indicated that placement ofthe molecuttings can be controlled by modifying standard testingprocedures.The in-place dry density can be measured using thenuclear density meter and the laboratory reference dry densitydetermined by modifying the currently specified compaction tests.Details of the construction of the test fills, performanceand results of the plate load tests, and procedures for controlof placement and compaction of molecuttings are presented in thefollowing sections. 2.CONSTRUCTION OF TEST FILLSFour test fills were constructed for this study.Theorientation of the test fills is shown in Fig. 1.The soilsand details of placement for each test fill is presented below.2.1 Gravelly Sand Gravelly sand satisfying the requirements for Safety andNonsafety-Related Structural Fill Specifications 9763-8-5 and9763-8-4 was placed in 8-in. -thick loose lifts and compactedto a minimum of 95% of the maximum dry density as determined byASTM D1557, Method D.Satisfactory compaction was generallyachieved by applying water to the surface of the loose lift andcompacting with six coverages with the Mikasa double drum roller.Eight lifts of gravelly sand were placed and compacted, result-ing in a total height of about 4 ft.2.2 Molecuttings (Controlled Placement)The construction of this test fill was controlled to achievethe compaction requirements of Safety and Nonsafety-RelatedStructural Fill (i.e., 95% of the maximum dry density as deter-mined by ASTMMolecuttings were placed in 8-in. loose lifts and compactedto 95% compaction. To achieve 95% compaction, control of thewater content to within a few percent of the optimum water con-tent, and numerous coverages with the Mikasa double drum rollerwas required. Attempts at controlling the water content includedmixing of wet and dry molecuttings and adding water tocuttings with water contents 2 to 3% below optimum. Molecuttingsplaced at water contents several percent higher than optimumcould not achieve 95% compaction until sufficient drainage hadreduced the water content to near the optimum value.Eight liftsof molecuttings were placed and compacted resulting in a totalheight of about 4 ft.2.3 Molecuttinqs (No Special Controls)Construction of this test fill involved the placement of themolecuttings with limited control of water content and a specifiedcompactive effort. The molecuttings were generally placed inG-in. loose lifts and compacted by six coverages with the Mikasadouble drum roller.In some instances, water content control waslimited to permitting drainage of a compacted layer overnight be-fore placement of the succeeding layer.Eight lifts ofcuttings were placed and compacted. 2.4 Stratified Molecuttings and Gravelly Sand The first three lifts of this test fill were constructedthe same way as the test fill of Molecuttings (No Special Con-trols). The water content of the molecuttings placed for thethird lift was about 3% higher than optimum. The surface ofthe third lift was saturated and became severely rutted duringcompaction.Sandwiching layers of gravelly sand between layersof molecuttings was done to determine (1) if the gravelly sandprovided drainage of sandwiched layers of molecuttings and (2)the feasibility of constructing a backfill of stratifiedgravelly sand and molecuttings (which may be required in thezone of frost penetration).Therefore, lifts 4 and 6 were con-structed using gravelly sand.Lift 4 was compacted with sixcoverages of the Mikasa double drum roller and lift 6 was com-pacted to at least 95% compaction. Molecuttings for lifts 5, 7and 8 were generally placed in 8-in. loose lifts with limitedwater content control and compacted with six coverages of theMikasa double drum roller. 3. PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand The percent compaction of each lift was determined by per-forming in-place density tests and laboratory compaction tests.The average percent compaction of the gravelly sand test fillwas 97.4%.The in-place density for each lift, after compaction, wasdetermined by performing two 6-in. -diameter Sand Cone (SC)tests and three Nuclear Density Metertests.Theplace density determined by the NDM was generally performed atprobe depths of 4 in. and 8 in.The two SC tests were performedadjacent to two of the NDM tests to provide a comparison of thewater content and dry density measured by each 'method.The SCand NDM tests were generally performed within a 5-ft radius ofthe plate load test location. .One-point compaction samples were obtained adjacent to theSC and NDM test locations. The one-point samples were compactedin accordance with ASTM D1557, Method D.The maximum dry densityfor the one-point sample was determined by plotting the one-pointdry density on a family of curves for the gravelly sand and in-terpolating the maximum dry density.The percent compaction wascomputed by dividing the in-place dry density by the correspondingone-point compaction determined maximum dry density.Table 1presents the summary of the percent compaction achieved in thetest fill.A profile of the test fill and the average percentcompaction for each lift is shown on Fig. 2.Three compaction tests were performed in accordance withASTM D1557, Method D, on bag samples of gravelly sand obtainedfrom material placed in lifts 2, 4 and 7.The compaction curvesand related grain-size curves performed by Pittsburgh Testing Labsare shown on Figs. 4 and 5, respectively.3.2 Molecuttings (Controlled Placement)The average percent compaction achieved for this test fillwas 96.7%.The in-place density of each lift after compactionwas determined by performing several NDM tests and, when thesoil conditions were acceptable, oneSC test.The SC test was performed adjacent to a NDM test to provide acomparison of the water content and dry density measured by eachmethod. Observations in the field and data from tests indicatedthat the hole excavated for the SC test tended to squeeze in orreduce in volume when the molecuttings were placed and compacted at water contents above or near optimum.Results from the SCtests when these conditions existed gave unreasonably high drydensities, and, as a result, SC tests were considered valid onlywhen they were performed in areas where the water content of themolecuttings was less than 5%. A more complete discussion ofthis problem is presented in Section 5.The SC and NDM testswere generally performed within about a 5-ft radius of the plateload test.Generally, several NDM tests were required before a lift ofthe molecuttings was compacted to a dry density that was esti-mated to provide 95% compaction. One-point compaction sampleswere obtained adjacent to the series of NDM and SC tests that, indicated about 95% compaction had been achieved.The one-pointsamples were compacted in accordance with ASTM D1557, Method C,except the minusmaterial was included for compaction.The maximum dry density for the one-point sample was determinedby plotting the one-point dry density on a family of compactioncurves for molecuttings and interpolating the maximum dry density.Correction of the in-place dry density to account for theplusmaterial, which was removed for the laboratory test,was necessary in order to determine the percent compaction. De-tails of the correction procedure are presented in Appendix A.The percent compaction was computed by dividing the correctedin-place dry density by the corresponding maximum dry densitydetermined by the one-point compaction technique.Table 2 pre-sents the summary of the percent compaction achieved in thetest fill. A profile of the test fill and the average percentcompaction for each lift is presented in Fig. 2.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on l&-in. sieveon bag samples of molecuttings from lifts 4 and 6.The compac-tion curves and related grain-size curves are shown on Figs. 6and 7, respectively.3.3 Molecuttings (No Special Controls)The average percent compaction of this test fill was 93.0%.The water content of the molecuttings during placement was gen-erally above optimum and was not controlled during compaction.Sand Cone tests to determine the in-place dry density were notperformed because of the inaccuracy in performing the test inmolecuttings compacted at water contents near or above optimum.The in-place dry density was determined by performing at least two and most usually three to five NDM tests at probe depthsof 4 and 8 in.The NDM tests were generally performed withina 5-ft radius of the plate load test location.One-point compaction samples were obtained adjacent'to theseries of NDM tests that indicated the next lift of molecuttingscould be placed.In some cases after a lift had been compacted,NDM tests performed, and one-point samples obtained, the liftwas permitted to drain overnight and additional NDM tests takenin the morning. One-point compaction samples generally were notobtained for the NDM tests performed after drainage. The pro-cedure to compute the percent compaction for each in-place den-sity test was the same as described in the previous section.Table 3 presents the summary of the percent compactionachieved in the test fill. A profile of the test fill and theaverage percent compaction for each lift is presented in Fig. 3.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on thesieve on bag samples obtained from lifts 2A and 7A. The com-paction curves and the grain-size curve for lift 2A are shownon Figs. 6 and 7, respectively.3.4 Stratified Molecuttings and Gravelly SandThe average percent compaction of the gravelly sand andmolecuttings test fill was 92.8%.Molecuttings were used forlifts 1, 2, 3, 5, 7, and 8 for this test fill.The in-placedry density and percent compaction of the molecuttings was deter-mined in accordance with the procedure described in the previoussection. Lifts 4 and 6 of the test fill were constructed usinggravelly sand. The in-place density for lift 4 was determinedby four NDM tests. One SC test and 3 NDM tests were performedin lift 6. The maximum dry density and computation of the per-cent compaction at each in-place density test location was asdescribed in the section for gravelly sand.Table 4 presentsthe summary of the percent compaction in the test fill. A pro-file of the test fill and the average percent compaction of eachlift is presented in Fig. 3. 4.PLATE LOAD TESTSFive plate load tests were performed on the four testfills.The plate load test number, test fill and date of thetest is presented below.Plate Load Test No.Test FillDate of Test1Gravelly SandJune 7, 19792MolecuttingsJune 14, 1979(No SpecialControl) .StratifiedJune 15, 1979cuttings andGravelly SandMolecuttingsJune 18, 1979(ControlledPlacement)5Molecuttings(No SpecialControl)The locations of the tests are indicated on Fig. 1 and de-tails of the procedure are presented in Appendix B.In briefthe procedure was as follows:an-diameter steel platewas generally placed 12 in. below the surface of the test filland loaded to produce contact stresses to 4 tsf and then to 12Deflections of the plate were measured and recorded.The results of the plate load tests are presented in Figs.B2 through B6. Values of Young's Modulus, E, were calculatedfrom the results of the plate load tests using elastic theory.A description of the analysis is presented in Appendix B. Asummary of the modulus calculated for each test is presented inTable 5.The percent compaction indicated in Table 5 representsthe average percent compaction of lifts within the zone of signi-ficant stress increase due to the load on the plate.For anin. -diameter plate this zone is aboutto 36-in.-thick.The soil modulus determined by the plate load test vs per-cent compaction is plotted on Fig. 8.The results indicate thatthe molecuttingshave a much higher modulus than the gravelly sandwhen both materials are compacted to the same percent compaction.In fact, the modulus of the molecuttings compacted to 93% compac-tion is approximately equivalent to the modulus of the gravellysand placed at 97% compaction.Plate Load Test No. 5 (PLT-5) wasperformed 13 days after and about 4 ft away from Plate Load TestNo. 2 (PLT-2).The soil modulus for PLT-5 was about two timesJune 27, 1979 the modulus for PLT-2. The increase in modulus may have beencaused by densification of the molecuttings as a result ofdrainage over the 13 day period between the performance of thetwo tests. Assuming that the molecuttings were saturated afterPLT-2 and the water content reduced by 1% during a period of 13the in-place dry density would have increased by 2 to 3 pcfor about a 1 to 2% increase in the percent compaction.Themodulus for PLT-5, as a result of the densification, nearly plotson the line from PLT-2 to PLT-4.Test PLT-3 was performed on the stratified molecuttings andgravelly sand test fill. The average percent compaction of themolecuttings and gravelly sand was 92.5 andrespectively., Plate load tests, PLT-2 and PLT-1, were performed on separatetest fills of molecuttings and gravelly sands compacted to aboutthe same percent compaction and the moduli were 7,300 psi and 10,100respectively.The moduli determined for the stratified testfill, however, was 17,000 psi.Based on the results of PLT-1 andPLT-2 the anticipated modulus determined by FLT-3 was between 8and 10,000 psi.The high modulus measured by PLT-3 may have beencaused by one or more of the following factors:1.Distribution of the load may have been more rapid forthe layered fill than in a homogeneous fill, and2.Drainage of the molecuttings and related increases indry density and modulus may have accelerated faster inthe stratified test fill than in the homogeneouscuttings (No Special Controls) test fill due to drainagethrough the gravelly sand layers. | |||
: 5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS The purpose of this section is to present recommendationsfor the placement and field control of molecuttings based onfield and laboratory data obtained during construction of thetest fills.Review of the data obtained provided the information neces-sary to make recommendations on the limits for grain size, liftthickness, determination of in-place density and percent compac-tion, and control of water contents of the molecuttings. Adiscussion of each of the items is presented below.5.1 Grain-Size LimitsGrain-size analyses were performed on thre'e samples of themolecuttings used for the test fills.The grain-size curvesare presented on Fig. 7.The molecuttings were generally widelygraded with uniformity coefficients of 45 to 100.The maximumparticle size was generally less than 3-in.-diameter and thepercent by weight passing the No. 200 sieve was from 5 to 7%.Based on these and other grain-size analyses recommendations forgradation requirements were developed and are presented inAppendix A.5.2 Lift ThicknessThe molecuttings were placed in 8-in.-thick loose liftsduring construction of the test fills. Observations made duringplacement of the molecuttings indicated that the ability toachieve a specific percent compaction was mostly affected by thewater content of the material rather than the thickness of thelift. When the molecuttings were placed at water contents aboveoptimum, a specific degree of compaction generally was notachieved until the water content was reduced to'or below theoptimum water content as a result of drainage.The time requiredfor drainage is a function of the lift thickness and, therefore,where 95% and 93% compaction is required, lift thicknesses of8-in. andare recommended.Thethick loose lift inareas where 93% compaction is required was recommended based onthe fact that the average percent compaction of 93.0% was achievedfor the molecuttings (No Special Controls) test fill without thebenefit of extensive compactive efforts. | |||
5.3 Determination of In-Place Dry Density The nuclear density meterprovides a much fasterdetermination of the field in-place dry density and water con-tent than the sand cone (SC).The accuracy of the NDM testsperformed in the gravelly sand and molecuttings was verifiedby comparing the results of adjacent NDM and SC tests.5.3.1 Gravelly Sand Generally, two SC tests were performed adjacent totwo NDM tests on each lift of the test fill to com-pare the in-place dry density and water contentmeasured by each method.. The in-place water con-tent determined by the sand cone versus nuclear den-sity meter is plotted on Fig. 9.The data indicatethat both methods measure essentially the same watercontent at values less than 8% and, as the water con-tent increases, the NDM measures a lower value thanthe SC. As a result, a correction was applied tothe water content measured by the NDM to compute thein-place dry density... A plot of sand cone versusnuclear density meter determined in-place dry densityis shown on Fig. 10.The correlation of the densi-ties determined by each method was considered to bepoor.The correlation may have been improved ifmore frequent moisture checks had been performed dur-ing construction of the test fill.5.3.2Molecuttings Twelve-inch-diameter sand cone tests were performedin the molecuttings to reduce the effects that themaximum particle size and percentage of materiallarger than thesieve would have on in-place drydensity determination. The in-place dry density andwater content determined by the SC test was comparedto the results from adjacentNDM tests.Comparison of the results indicated the water contentdetermined by the NDM averaged 1.7% higher than thatdetermined by the sand cone.The 1.7% difference inwater contents was confirmed by performing water con-tent checks at random NDM test locations. A 1.7% biascorrection was applied to the water contents determinedby the NDM. A plot of sand cone determined water con-tent versus nuclear density meter water content (with a1.7% bias correction) is presented on Fig. 11. | |||
The plot shows there is a good correlation betweenthe sand cone and nuclear density meter (after biascorrection) water content determinations.A secondwater content check was made on molecuttings. afterthe test fill was completed which indicated thatthe bias had increased to 2.5%.Because the watercontent bias changed significantly within a periodof two weeks periodic checks of the bias arerecommended.The in-place dry density determined by the sand conetest and the 8-in. NDM test after correction for thewater content bias is plotted on Fig. 12.The soliddots and dashed circles represent in-place dry den-sity measurements at water contents less than 5% andgreater thanrespectively.The data indicatethat there is good correlation of dry densities deter-mined by both methods at water contents less than 5%and that the SC measured higher dry densities thanthe NDM at water contents above 5%.For this testfill the SC tests performed in molecuttings compactedat water contents above 5% are not considered validfor the reasons presented in the following discussion.When the molecuttings were placed at water contentsabove aboutthe compacted surface would exhibit aspongy behavior when one walked across the surface.The degree of sponginess increased as the moistureincreased above the optimum water content.Thesponginess is believed to be caused by water and airpore pressures. The net effect was that as the sandcone hole was excavated the pore pressures at thewalls of the hole were relieved by the walls movinglaterally into the hole until an equilibrium of thepore pressure at the walls of the hole was reached.Thus, by the time the volume of the hole was measureda significant decrease in the volume of the hole hadoccurred but the quantity of soil excavated was fromthe original volume.The result was that the dry soilexcavated was divided by awhich re-sulted in an inaccurately high computed dry density.The SC and NDM test results indicate that the NDM canbe used to determine the in-place dry density and watercontent of molecuttings. The water content bias shouldbe checked periodically to account for changes thatoccur in the molecuttings. Details of a recommendedplacement procedure arepresented in Appendix A. | |||
5.4 Determination of Percent Compaction The field and laboratory data indicated the nuclear densitymeter could be used to determine the in-place dry density afterthe appropriate water content bias had been determined for themolecuttings being tested.The preferred field procedure for determing the percent com-paction of compacted soil is as follows:1.Gbtain a one-point sample of the soil before compaction.2.Perform the' one-point compaction test in the lab anddetermine the maximum dry density from a family ofcurves.3. Perform the in-place dry density of the compacted liftusing the nuclear density meter at or near thelocation of where the one-point sample was taken.This procedure can be used for the molecuttings if at leastthree nuclear density meter determinations of the in-place drydensity are made. The average of the three tests should be usedto represent the in-place density for computation of the percentcompaction. The above procedure will reduce the effect that minorin the character of the molecuttings will have on thein-place dry density determination.The use of a standard laboratory compaction test or one whichwas slightly modified was considered the best method of deter-mining the maximum dry density of the molecuttings.The ModifiedAASHG Compaction Test, ASTM D1557, permits the use of minusmaterial to be compacted in 6-in. molds.Grain-size analysesperformed on molecuttings indicate that nearly 50% of the sampleis retained on thesieve, and, as a result, the materialpassing thesieve would behave much differently than thetotal sample during compaction. A sample of the molecuttings thatwould represent the compaction behavior of the material was con-sidered possible if the amount of coarse material removed waslimited to about 20% by weight of the total sample.This couldgenerally be achieved by removing material retained on thesieve.For the test fill the laboratory compaction used was ASTMD1557, Method C, except the plusmaterial was removed.Because this compaction test, as modified above, was used for thetest fill and gave reasonable results its use is recommended forperforming laboratory compaction tests on the molecuttings. | |||
5.5 Water Content Control The laboratory compaction curves for compaction tests per-formed on samples of molecuttings show a sharp peak in dry densityat the optimum water content, Fig. 6.The dry density drops asthe water increases or decreases from the optimum value.Thelaboratory data show that small variations in water content sig-nificantly affect the degree of compaction that can be achievedin the molecuttings. This behavior was also observed duringplacement and compaction of the molecuttings in the test fills.In the test fill where placement of the molecuttings was con-trolled, the required percent compaction generally could only beachieved by controlling the water content, by either wetting ordrying, of the molecuttings.The most efficient compaction of themolecuttings was when the water content was from about 4 to 6%.Therefore, the water content of the molecuttings should notdiffer from optimum by more than +for most efficienttion. | |||
TABLES TABLEOF FIELD DENSITY TESTS.GRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNo.SampleNo.PercentND-1One-point120.9ThiscolumnND-2samplesnot123.7doesnotap-ND-3obtained121.1plyforcompac-SC-1118.1tiontestper-formedusing2SC-111.19.7120.9123.0115.0ASTM93.5ND-24.810.0116.8120.5117.1Method D97.2SC-39.49.0120.1123.0120.397.88.19.2117.9122.0119.5N.A.13.0122.31 2 2 . 3119.23ND-1One-point123.0SC-2samplesnot126.0ND-3obtained121.4122.5N.A.I5.2I115.5122.1121.548.54.9117.8125.5119.194.98.54.9117.8125.5120.596.05.07.4119.1124.0124.1100.05.0.7.4119.1124.0118.895.8ND-55.8I7.0121.5126.0119.094.4NOTES:One-point compaction sample performed by Pittsburgh Testing Labs.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLEOF FIELD DENSITY TESTSGRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2NO.SampleNo.One-PointLaboratoryMaximumDry DensityIn-PlaceDrDensitypcfPercentCompactionPercentMaterialWaterContent%DensityForMaterial4.89.7124.5125.0125.5100.44.89.7124.5125.0123.899.05.810.3123.1124.0120.997.513.09.3126.4127.0124.998.013.09.3126.4127.0121.395.53.910.0122.3123.2117.895.613.28.4126.0127.0118.793.513.28.4126.0127.0125.799.09.17.6123.3126.5123.097.29.17.6123.3126.5126.699.75.96.8120.5126.5122.596.85.9120.5126.5123.897.910.77.8121.0124.8121.697.410.77.8121.0124.8123.298.711.37.6121.5125.8121.996.9ND-lOne-point119.6SC-2samplesnot118.9ND-3obtained120.2SC-4118.8IN.A.13.8117.9120.9116.2.NOTES:(1) One-point compaction sample performed by Fittsburgh Testing Lab.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.(3) Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geo technical Engineers Inc.Project 76301July 12, 1979 PLACEMENT)FILLTABLEOF FIELD DENSITY TESTSQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNO.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density, pcfPercent%PercentMaterialWaterContento0DryDensityTotalCorrectedForMaterial1ND-12One-pointN.A.145.5N.A.N.A.ND-13samplesnotN.A.144.0N.A.N.A.ND-14obtainedN.A.142.6N.A.N.A.ND-15N.A.146.9144.5N.A.2ND-810.85.1145.4151.0150.0146.997.324.95.1146.0151.5149.5140.993.0(1)7.3.7153.0161.5152.4150.5158.498.43ND-1011.44.6145.9152.0143.1139.091.4ND-1110.4.14.4144152.5151.8145.5152.4.150.7142.8149.898.293.999.24ND-l7.35.0151.2154.0149.4147.495.78.24.6148.3154.0148.3145.994.76.84.3144.9142.792.6.149.797.2NOTES:One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.Project 76301July 12, 1979 MOLECUTTINGS (CONTROLLED PLACEMENT) TEST FILLQUARTZITE MOLECUTTINGS STUDYTABLEOF FIELD DENSITY TESTSSTATIONPage 2 of 2LiftNo.SampleNo.One-PoirMaximumDensityIn-PlaceDensity,MaterialWaterContent%DensityCorrectedForMaterial5ND-85.64.9148.7155.0150.6149.17.74.1146.5155.0148.0145.714.54.7146.0149.4145.0.162.3160.66ND-416.94.0146.0155.0152.6146.0ND-57.84.5147.9153.0150.2148.17.54.2148.3154.0152.3150.4148.3154.07ND-412.54.9145.21 5 1 . 0147.1143.1ND-512.25.0147.5152.0149.5145.9ND-610.44.6146.3152.0147.6144.48ND-lOne-point146.0N.A.ND-2samplesnot146.5N.A.ND-3obtained146.1N.A.PercentCompaction96.294.094.895.596.897.794.896.095.0N.A.N.A.N.A.NOTES: (1) One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.July 12, TABLE 3OF FIELD DENSITY TESTSMOLECUTTINGSSPECIAL CONTROLS) TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATION 2LiftNo.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density,PercentCompactionPercentMaterialWaterContent%DensitySampleCorrectedFor +Material1ND-4One-point146.3N.A.ND-5samplesnot142.4N.A.ND-6obtained145.5N.A.ND-7149.1149.1N.A.2ND-412.34.6147.7155.0149.4145.794.0ND-510.65.8149.0152.0145.8144.595.1ND-614.55.5149.6152.0145.8142.393.6SC-712.34.6147.7155.0157.8154.591.03ND-56.06.7147.0151.0143.7141.793.8ND-69.26.2147.8151.0141.9.138.591.74ND-l10.66.5148.8151.1144.7141.193.3ND-215.56.6146.0151.0143.0137.190.85ND-l12.34.9148.9153.0150.9147.596.4ND-212.35.0148.1152.0152.2149.098.0ND-324.84.7147.7153.0140.5129.084.36ND-523.54.3153.3156.0154.2147.794.7ND-68.53.6145.1153.0145.1142.393.0ND-79.45.6153.6155.0143.3140.090.3Geotechnical Engineers Inc.Project 76301July 12, 1979 3OF FIELD DENSITY TESTS.SPECIALTEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2CompactionLaboratoryMaximumDryDensityIIn-Place Dry Density, pcfPercentCompaction%WaterContentDryDensityCorrectedForMaterial78ND-7ND-8ND-9ND-1ND-2ND-35.14.07.5One-pointsamplesnotobtained3.13.43.9141.2140.1143.6149.0148.0151.0140.0139.2148.8144.4125.0144.3138.1137.7146.6N.A.N.A.N.A.92.793.097.1N.A.N.A.N.A.Geotcchnical Engineers Inc.Project 76301July 12, 1979 4OF FIELD DENSITY TESTS STRATIFIED MOLECUTTINGS AND GRAVELLY SAND TEST FILLQLJARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 1LiftNo.SampleNo.One-PairnLaboratoryMaximumDryDensityDensity, pcfPercentPercent+Material%WaterContentDryDensityTOY-11CorrectedForMaterial3ND-715.05.7149.3153.0148.8144.194.2ND-812.26.0148.8152.0145.9141.893.35.6118.3125.0114.3N.A.91.4ND-42.7122.2124.0108.1N.A.87.2ND-53.0115.1123.0108.2N.A.88.0ND-64.9116.9124.5N.A.88.85ND-410.44.3145.7151.0151.3148.5ND-516.33.8144.8153.0138.1130.8N.A.N.A.123.31.27.5123.8N.A.97.17.2123.3127.5121.1N.A.95.0ND-36.8118.8124.5119.3N.A.95.8ND-48.3120.3124.0119.6N.A.96.57ND-104.82.7137.5148.0140.2138.493.58ND-4Onepoint147.3N.A.N.A.ND-5samplesnotobtained140.8N.A.N.A.NOTES :construction or Lift.(2)Values represent percentmaterial.(3)Nuclear density probe may have penetrated gravelly sand layer below.(4) One one-point compaction sample obtained for SC-1 and ND-2.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLE 5SUMMARY OF PLATE LOAD TESTS RESULTSQUARTZITE MOLECUTTINGS STUDYSTATIONLoadNo.SoilAtTestSoilModulus,psiAveragePercentCompaction1R e m a r k sVirginReload1GravellySand97.12Mole92.6(NoSpecialControl)3StratifiedAve. PercentMoleCuttingsandGravellyCompaction93.7Sand4Mole95.3(ControlledPlacement)5MoleCuttings(NoSpecialPerformed13daysafterControl)PLT-2Geotechnical Engineers Inc.Project 76301July 11, 1979 FIGURES PLAN VIEWTEST FILLSic ServiceofProjectStudyMolecuttingsPLT-3GravellycuttingsSandStratified Mole-cuttings andGravelly Sand(ControlledPlacement)LT-5PLT-4PLT-1PLT-2cuttings(No SpecialNot To Scale PROFILE OF GRAVELLY SANDTEST FILLSteel PlateLift 7 Ave.Comp. = 97.5Lift 6 Ave.Comp. = 97.0Lift 5 Ave.Comp. = 98.1. Lift 2Ave.% Comp. = 97.4Lift 1 Ave.Corns. = 99.0Lift 4 Ave.= 96.2Lift 3 Ave. % Comp. = 100.6Scale:= 2.5'1. One-point compaction samples not obtained.Average percentcompaction is based on maximum dry density provided by PTL.PROFILE OF MOLECUTTINGS(CONTROLLED PLACEMENT) TEST FILLSteel PlateAve.Comp. = 95.3Lift 6 Ave. %= 96.7Lift 5 Ave.Comp. = 95.0Lift 4 Ave. % Comp. = 95.1Lift 3 Ave.= 95.7Lift 2 Ave.96.2Lift 1 Ave.Comp. = N. A.Scale:= 2.5'Molecuttings l -PROFILE OF TEST_ FILLSProject 7630111, PROFILE OF MOLECUTTINGS(NO SPECIAL CONTROLS) TEST FILLLift 1 Ave.Comp. = N.A.Scale:= 2.5'PROFILE OF STRATIFIED MOLECUTTINGSAND GRAVELLY SAND TEST FILLServiceofIMolecuttingsIPROFILE OFFILLSStudyProject11, 19g .Steel Plate (PLT-2and 5)Lift 8 Ave.=Lift 7 Ave.= 94.3Lift 6 Ave.Comp. = 92.7Lift 5 Ave.Comp. = 92.9Lift 4 Ave.Comp. = 92.1Lift 3 Ave. % Comp. = 92.8Lift 2 Ave.Comp. = 94.7.Steel Plate (PLT-3)Lift 8 Ave. % Comp. = N.A.Lift 1 Ave.= N.A.Scale:2.5' U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDRCMETER6432IofLabs.Pro-iIGrain-size analyses per 'formed,..COBBLESCOARSEIFINECOARSEMEDIUMIFINEWINCHESTERMASSACHUSETTS3 4 6GRAIN SIZE MILLIMETERSSIZEQuartziteMolecuttingsGRAVELLY SANDStudyITEST FILLIIi11, 1979 NOTE: 1. Compaction test performed inwithC,the plusmaterial. was discarded and no limitationplaced on the percent retained on thePublic Service Company ofNewhireQuartzite MolecuttingsStudyProject 76301. COMPACTION CURVESMolccuttingsJuly 12, 1979Molecuttings- V W - -ControlledMolecuttings(No Special Controls)(Controlled Placement)Lift 4s = 100%-Gave = 2.83 (De152..02468IOWater Content, U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETERGRAIN SIZE MILLIMETERSCOBBLESSANDFINEGRAIN SIZESAMPLES OFMOLECUTTINGSQuartziteMolecuttingsstudyICOARSE FINE COARSEMEDIUMWINCHESTER . MASSACHUSETTSanalyses performedusing successive elutriation.MOLECDTTINGSMOLECUTTINGSLIFT 2LIFT 4I -I - -500100505I0.561(No Special Controls4 32I820 30 40 50 70200MOLECUTTINGS(Controlled Placement)(ControlledPlacement)0.050.001 | |||
.MOGravelly Sand302520151050PERCENT COMPACTIONVERSUS9092349698100Percent ofof Modified AASHO, %NOTES: 1. Modulus of elasticity computed using theory of elasticityfor semi-infinite, isotropic soil.2.Modulus of elasticity value plotted is minimum value fromvirgin loading curve.3.Percent compaction is the average percent compaction ofthe first three layers of soil under the plate.4.Percent compaction the average percent compaction of twolayers of molecuttings and one layer of gravelly sand.5.Range in percent compaction is estimated.See discussion in text.Public Service Company ofQuartziteMolecuttingsStudy76301 4.06.08.014.0Nuclear Density Meter Determined In-Place Water Content,WATER CONTENTSAND CONE VSDENSITY METERGRAVELLY SANDJu98 . 06 . 0Estimated Line ofGravelly SandBest Fit Gravelly Sandr11114116118122124126Density Meter Determined In-Place Dry Density, pcfNOTES: 1. In-place dry density includes plusmaterial. .2.In-place dry density based on 8-in. deep nuclear test.Densitieshave been corrected for water content bias according to plot ofversusnuclear for gravelly sand:conedevice3.Cone and Nuclear Density Meter determinations were performedto each other (about 6-12 in. apart).SAND CONE VS NUCLEAR DENSITY METER DET.DRY DENSITYGRAVELLY SAND10.-.--.----PublicCompany of.Elcwi L-CIIIIIQuartzitestudyProject 76301 Nuclear Density Meter DeterminedWater Content,(after bias was corrected)8 . 07 . 06 . 0Molecuttings3.04.05.06.07.08.0NOTES: 1. In-place water content is baseddeep nuclear test. | |||
135145150155160Nuclear Density Meter Determined In-Place DryDensity,NOTES: 1. In-place dry density is uncorrected for the plusmater2..except where noted.3.Water content of Sand Cone was greater than 5.0%.4.In-place density is based on 4-in. deep nuclear test.MolecuttingsPublic Service Company ofSAND CONE VS NUCLEARiSITY METER DET. IN-PLACEDRY DENSITYMOLECUTTINGSI.QuartziteMolccuttingsStudyProject 7630111, APPENDIX ASAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35in.75-1032-O22-o10-O2.The uniformity coefficient,should be notless than 5.B.PLACEMENT1.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 95% of maximum dry densityas determined by ASTMwith exceptions fortesting noted in Section C.2.2.The water content of the molecuttings should be atoptimum1% during placement. The water contentduringof quartzite molecuttings shouldbe stockpiled or otherwise treated to reduce thewater content to less than 6%.If the water contentis less thanthe addition of water during com-paction will be necessary if satisfactory compactionis to be achieved.3.Molecuttings should not be placed in direct contactwith pipes, culverts, or other structures sensitiveto abrasion and/or high point loads.4.The pore fluid of the molecuttings is brackish and,as a result, the resistivity of the muck is likelyto be below the minimum limit of 10,000United Engineers is to develop recommendations forplacement of the molecuttings in areas when highresistivity of backfill material is required. | |||
C.TESTING AND FIELD CONTROLDue to anticipated variations in rock type thecuttings should be monitored daily by determining thegrain-size distribution, water content, and rock typefor at least one typical sample.The grain-sizeanalysis should be performed by using a wet sievingtechnique and every tenth test should be performedby using the elutriation method, without pre-dryingof the sample. The frequency of testing may be re-duced in time after those testing become familiar withthe material and thus capable of judging when thematerial is or is not acceptable.a.If the percent passing thesieve materialis greater thanthe material should not beused.b.If the water content is greater than 1% aboveoptimum, the molecuttings should be stockpiledor treated to reduce the water content to optimum.2.A family of at least three compaction curves should bcdeveloped using ASTM D1557, Method C, except that theminusmaterial shall be used. Each compactioncurve should be accompanied by a grain-size analysis.Additional compaction curves should be performed onceevery 7,500 yards or earlier if visual changes in themolecuttings grain size is observed.3.A bag sample of the molecuttings should be obtainedafter the loose lift has been placed and before com-paction begins. The sample should be large enough toperform a laboratory one-point compaction test and tomeasure the percent material retained on the l&inchsieve.4.Separate the plusmaterial and calculate itspercentage by weight of the entire sample.5.A one-pointtest should be'performed on thebag sample of molecuttings in accordance with ASTMD1557, Method C, except that the minussievematerial shall be used.The maximum dry density for this sample, yd , is determined by plotting thepoint dry on the family of curves and inter-polating the maximum dry density for the minusmaterial.6.The in-place dry density should be determined by per-forming at least three nuclear density meter tests.The average dry density should be used to computethe percent compaction.This method should reduce theeffects of sharp variations in the molecuttings on thein-place dry density determinations.a. The water content bias for the nuclear densitymeter should be corrected for use in molecuttings.The water content bias should be checked weekly.7.The percent compaction is determined by dividing thecorrected in-place dry density by the laboratory maxi-mum dry density as determined in 6. above. A formulato compute the corrected in-place dry density, tocorrect for the quantity of plusmaterial, ispresented below. = 1-Rwhere= corrected in-place dry density for theminussieve material= average in-place dry density determinedby using nuclear density meter= unit weight of waterG = specific gravity of molecuttingsR = percent, by weight of the total sampleretained on thesieveThe percent compaction is computed as follows:Percent Compaction P(%) =x 100.= Maximum dry density of minusmaterialdetermined in Step 5. from the family ofcurves and the one-point compaction.YND NONSAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35100-1775-10No. 2022-o10-O2.The uniformity coefficientnot be lessthan 5.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 93 of maximum dry density asdetermined by ASTM D1557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Molecuttings can be sandwiched between presently ac-cepted gravelly sand structural fill. Whencuttings and gravelly sand are alternated in the back-fill, the following limits are recommended.a.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 93maximum dry densityas determined by ASTMb.Gravelly sand should be placed in accordance withthe present specification for structural fill (i.e.,8-in. loose lifts compacted to 95% of ASTM3. The water content of theshould beoptimum1% during placement if no gravelly sand layersare present. When the molecuttings and gravelly sandare placed in alternating layers, the water content ofthe molecuttings may be permitted to be as high as 2%above optimum.If the water content of the molecuttingsexceeds the suggested limits of water content, thecuttings should be stockpiled or otherwise treated toalter the water content.If the water content is low,say 2 tothe addition of water during compactionmay be necessary to achieve satisfactory compaction. | |||
RANDOM FILLA.MATERIALThe molecuttings to be used asFill should complywith the present specification as described in Specification No.9763-8-4, Section 3.2.2 dated September 27, 1974.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 90 of maximum dry density asdetermined by ASTM Dl557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Although limits on the water content of thecuttings are not necessary, the most efficient com-paction will occur at optimum water content1%.C.TESTING AND FIELD CONTROLTesting and field control for use of molecuttings as Ran-dom Fill should be the same as outlined for Safety-Related areaswith the following exceptions:The gradation of the molecuttings should comply withpresent specifications for Random Fill.No limit on the water content of the molecuttings isrecommended.The maximum permissible water contentin the field will be dictated by the ability toachieve the required percent compaction. | |||
APPENDIX | |||
APPENDIX BPLATE LOAD TESTB-l PurposeThe plate load tests were performed to determine the de-formation characteristics of gravelly sand and molecuttings.The results of the plate load tests provided the basis forcomparison of the two materials and to determine the effectthat percent compaction has on their deformation characteristics.. B-2 ProcedureFor each test a 24-in. -diameter hole was excavated to adepth of 12 in., except for test PLT-3 which was 6 in. deep.An -diameter, thick steel plate was placed on athin layer of liquid hydrous stone which was placed directlyon the bottom surface of the test hole. Additionalsteel platesandin diameter were placed in apyramid arrangement on top of theplate.After the hydrous stone and plates were in place, theplate was loaded by a hydraulic jack reacting against the under-side of a loaded, flat-bed trailer, as illustrated in Fig. B-l.The loads were measured using a calibrate pressure gage.Deformations of the plate were measured using three dialindicators attached to a reference beam as illustrated in Fig.B-l. The dial indicators were graduated to mm. The ref-erence beam supports were separated from the center the plateby about 72 in., which was a sufficient distance for deflectionsunder the supports to be negligible during loading of the plate.The loading sequence for each test was as follows:1.Applied load to develop contact stress of 4 tonsper square foot (tsf) in four equal increments.2.Unload to zero load in two equal increments.3.Repeat load-unload cycle to 4 tsf.4.Load to develop contact stress of 12 tsf in sixequal increments. | |||
EDS-2-5.Unload to zero load in three equal increments.6.Repeat load-unload cycle to 12 tsf two more times.Each loading or unloading increment was held constantuntil the rate of deformation of the plate was less than.001The air temperature when the plate load tests were per-formed was aboutF.B-3 ResultsThe load versus displacement curves for the five plate loadtests are illustrated in Figs. B-2 through B-6.The slope ofthe virgin load curve was generally straight except for testPLT-2 and PLT-3 where slight curvature was observed.The slopeof the reload curves were much flatter than the virgin curveand the slopes of the repeated reload-unload cycles were parallelas would be expected.Values of Young's Modulus, E, were calculated from the re-sults of the plate load tests using elastic theory.The solutionfor the settlement of a loaded, rigid circular plate on anelastic half space is as follows:where s = settlementq = average stress on the plateP = load on the plateD = diameter of the plate= Poisson's ratioI = influence factor =E = Young's ModulusAssuming a value v = 0.3 and rearranging to compute E, yields:The modulus calculated is the average modulus within the zoneof significant stress which for anplate would extend between18 to 36 inches beneath the plate.The moduli calculated using this method are presented in TableFor each test tangent moduli were calculated using the straightsegments of the load and reload curves. | |||
PLATETEST EQUIPMENTWINCHESTER .Project 76301Julv 12, 1979PublicofNew HampshireReaction Structure (Loaded Flat-bed Trailer)\ LiquidHydrousStoneBearing PlatesDial IndicatorBeamRefBeamSupportof Test FillNOTE: 1.Depth for PLT-3 was about 6-in.Schematic Illustration of Plate Load Test Equipment--(Not ToDialSteel Bearing PlateDial"Ear" Welded To Bearing PlateDial indicatorsandmonitored displacement of "ears" attachedto circumference of bearing plate.Plan---Locations of Dial Indicators(Not ToStudy 6 . 07 . 08 . 002.06.08.0. 10.012.0Vertical Stress. tsfDate Performed:June 7, 1979By:Fisher/R. GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONPLATE LOAD TESTGRAVELLY SAND...11I 802.04.06.010.012.0icof.QuartziteProject 76301StudyPLATETEST PLT-211.Vertical Stress, tsfDate Performed:June 14, 1979By:GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONCON.) | |||
41.2.3.04.06.08.0Vertical Stress, tsfDate Performed:June1979By: W. Fisher/R. GardnerPlate Diameter:Company of10.012.0VERTICALVSMolecuttingsStudyPLATE LOAD TEST PLT-3ST.GR.76301i 04 . c04.06.08.010.012.cVertical Stress, tsfDate Performed:June 18, 1979By:Fisher/R.GardnerPlate Diameter:MolecuttingsPLATE LOAD TEST PLT-4. . . . --a.---1.02.03.0DEFORMATIONStudy 02.04.06.08.010.012.0..Vertical Stress, tsfDate Performed:June1979By:FisherPlate Diameter:- -.STRESS VSDEFORMATIONPLATE LOAD TEST PLT-5MOLECUTTINGS -(NO SP. CON.-July 11,g .1 . 0.2 . 04 . 05 . 06.07.0IIIIIQuartziteStudy TABLESUMMARY OF FIELD DENSITY TESTSPageLiftSampleOne-PointCompactionLaboratoryIn-Place Dry Density, pcfNo.No.PercentWaterMaximumTotalCorrectedCompactionMaterialContentDensityDry DensitySampleForMaterialoa00% | |||
UPDATED FSARAPPENDIX 20GEOTECHNICAL REPORT DISCUSSION OF DERIVATION OFCOEFFICIENTS OFREACTIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
March 22, 1978Project 77386File No. 2.01017 MAIN STREET. WINCHESTER. MASSACHUSETTSMr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th Floor.Manchester, NH 03105 | |||
==Subject:== | |||
Discussion of Derivationof Coefficients ofReaction | |||
==Dear Mr.In the following we describe some techniques that we havedeveloped to convert the moduli obtained from triaxial tests tomoduli ofreaction for various loading conditions. Wepresent this information to complement various telephone con-versations with D. Pate1 ofComputation of Coefficients ofReactionThe coefficient ofreaction,== | |||
represents soildeformation, due to pressure acting along a boundary surface,as if the soil were composed of independent springs, each repre-senting a unit of area with a spring constantThe springconstant is defined as a pressure divided by a displacement.Such a representation is convenient for analytical purposes butneglects the influence of adjacent loaded surface areas on thedisplacement of any given point on the boundary surface.Thus,the coefficient ofreaction is not a unique number foran elastic material but is a function of the size of the loadedarea, the pressure distribution, and the geometry ofmaterial.For a soil, the modulus ofreaction is also dependent onthe method or sequence of loading, i.e., the stress path.On the basis of the theory of elasticity, wecomputedcoefficients ofreaction for the structural backfill andthe sand cement for three geometries of loading using the modulusof elasticity and Poisson's ratio data obtained in the triaxialtest results. The geometries of loading studied are illustratedin Figs. 1 through 9 and are as follows: | |||
Mr. JohnMarch 22, 19701.Circular or square footing subjected to vertical load.2.Pressure inside a cylindrical cavity in the soil massassuming a plane strain condition.This istive, for example, for the loading produced by thermalexpansion of the cross section of a buried pipe.3.Pressure inside a cylindrical cavity with simultaneousapplication of a vertical surcharge, p, and a horizon-tal pressure,This loading is an approximate re-presentation of the placement of fill over a buriedwhich deforms to produce an increased lateralstress around the pipe.A plane strain condition was.assumed.The modulus of elasticity and Poisson's ratio used in the compu-tations are strain dependent and were selected for the average strainin the region of the soil mass that contributes most to the displace-ments, namely, within a distance of one diameter from the pipe and onefooting width below the footing base. These strains were correlatedwith the displacements which, in turn, were expressed in terms offooting settlement divided by6/B, or in terms of thediameter strain of the pipe,In Figs. 1 through 9, the values ofthe coefficient ofreaction are plotted as a function of (T/Borand confining pressure. Confining pressure is to be taken asthe effective overburden pressure computed at the elevations shown inthe figures. An exception to the above procedure is that for the sur-charge type loading, a constant Poisson's ratio of 0.3 was used.The elastic modulus E and Poisson's ratio v used as a basis forthe coefficient of reaction computations were obtained fromtriaxial compression tests in which the minor principal stresses werekept constant and the major principal stress was increased monotoni-cally until the specimen failed. Such a stress path would be sufficientto determine E and v for an elastic material.However, soil is notelastic and E and v are dependent on the stress path or stress history.In particular, higher values of E would be obtained for repeated orcyclic loading. For the static load conditions, we feel that the valuesofreaction presented are reasonable estimates for the in-situloading conditions. As shown in the next section, the values comparewell with values given in published literature.We recommend, however,that when these values are used, sensitivity analyses should be made toassure that the designs are safe for a range 25% above and below thegiven values.Comparison With Published Coefficients ofReactionThe coefficients ofreaction obtained from thetestswere compared with data presented by K. Terzaghi in the paper entitled PrincipalGC/SJP:msEncl.ccR.YAECD.A. Desai,D. Patel,Mr. JohnMarch 22, 1978"Evaluation of Coefficients ofReactionGeotechnique,vol. 5, 1955, pp. 297-326.For shallow footings the vertical coefficient ofre-action for a one square foot plate, is estimated by Terzaghito range between 300 and 1,000 ton/cu ft for dense sands, i.e., arange for x B of 4,000 to 14,000 psi. These values are intendedfor shallow footings,a typical depth of embedment, Dof 4ft, and for a width, B, of one foot.Thus, they areof confining pressures equivalent to a depth of 4.5 ft or about 4 psi.The coefficient of horizontalreaction is given byTerzaghi for a 1 sq ft vertical area at a given depth, and it isassumed to be proportional to the effective stress at that depth.For example, for dense sands at a confining pressure of 10 psi, arange ofof 7,000 to 14,000 psi is indicated..Thedata for structural backfill, for strains of aboutFigs. 1, 2, 4 and 5, agree with Terzaghi's data.No specific infor-mation on strain level is given by Terzaghi for his data, but heindicates that the data are applicable to a factor of safety againstbearing capacity failure that is larger than two.It is also implicitthat the factor of safety would not be much more than 2.Perhaps itlies in the range of 2 to 4.For such factors of safety, the resultsof plate load tests on sands (1 sq ft plate) would indicate typicalsettlements of 0.1 in. to 0.3 in., which would be equivalent to avertical strain on the order of 1% in the soil adjacent to the plate.Thus, the data for the structural backfill obtained from the triaxialtests correspond to coefficients ofreaction within therange given by Terzaghi.Sincerely yours,GEOTECHNICAL ENGINEERS INC.Steve J. PoulosPrincipal FIGURES ReactionGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386Public Service Company ofNew Hampshire=March 13, 3.978Fig. 1SETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt462347Sand and Sand-CementBackfillPRESSURE ONBACKFILL90% COMPACTION ReactionSETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt B/2)..4IO'986544567 8 910234568sProject,.77386FOOTING PRESSURE ONSTRUCTURAL BACKFILL95% COMPACTIONMarch 13, 1978Fig. 2Public Service Company ofNew HampshireGeotechnicalInc.Winchester, M a s s a c h u s e t tSand and Sand-CementBackf ill 96SmSETTLEMENTk9765= EFFECTIVE VERTICASTRESS AT DEPTH445679102346789100Public Service Company ofReactionFOOTING PRESSURE ONNew HampshireSand and Sand-CementSAND-CEMENTBackf illBACKFILLEngineers Inc. ,Winchester,MassachusettsProject 77386March 13, 1978Fig. | |||
ReactionSand and Sand-CementBackf illEngineers IncWinchester, MassachusettsProject 77386Public Service Company ofNew HampshireMarch 13, 1978Fig. 4INTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILLCOMPACTIONIO'9765976541456 7 8 91023456 7 65489467 8 9102346ReactionProject 77386March 13, 1978Fia. 5Sand and Sand-CementBackf illINTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILL95% COMPACTIONPublic Servide Company ofNew HampshireGeotechnical Engineers Inc.Winchester,MassachusettsEFFECTIVE VERTICALSTRESS AT DEPTH Z2U=I IO986987463456 7 8 91023456 7 8Public Service Company ofNewGeotechnical Engineers Inc.Winchester,MassachusettsReactionSand and Sand-CementBackfillProject 77386March 13, 1978Fig. 6= EFFECTIVE VERTICALSTRESS AT DEPTHSAND-CEMENT BACKFILLINTERNAL PRESSUREPIPE BURIED INDISPLACEMENT ReactionDISPLACEMENT=98765= EFFECTIVE VERTICALSTRESS AT DEPTH4452346 7 8 9 0 0SURCHARGE PRESSURE ONPIPE IN STRUCTURALBACKFILLCOMPACTIONMarch 13, 1978Fig. 7Project 77386Sand and Sand-CementBackf illPublic Service Company ofGeotechnical Engineers Inc.Winchester, MassachusettsNew Hampshire 4567 8 910234564ReactionSand and Sand-CementBackf illProject 77386BACKFILL'95% COMPACTIONMarch 13, 1978Fig. 8ON PIPE IN STRUCTURALSURCHARGE PRESSUREInc.DISPLACEMENT= EFFECTIVE VERTICALSTRESS AT DEPTH ZPublic Service Company ofNew HampshireWinchester, Massachusetts UPDATED FSARAPPENDIX 2PSTATION CONTAINMENT AIRCRAFT IMPACT ANALYSISThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information. | |||
FSARAPPENDIX 2P STATION CONTAINMENTAIRCRAFT IMPACT ANALYSISPrepared byUNITED ENGINEERSCONSTRUCTORS INC.OCTOBER 1975PUBLIC SERVICE COMPANY OF NEW HAMPSHIRESEABROOK, NEWHAMPSHIRE CONTENTSABSTRACTl-ll-ll-12l-14l-15FSARCONTENTS1.0 Structural Analysis ofStation Containmentfor Aircraft Impact l-l1.1Introduction ------------------------------1.2Forcing Function for Impacting Aircraft1.3Behavior of Containment -------1.4Response of the Enclosure Building -----1.5Shear Capability of the Containment ----1.6Requirements to Prevent Perforation ----1.7Conclusions1.8References for Section2.0 Fire Hazard Analysis ofStation 2-l2.1CombustibleVaporProduction 2-22.2FireAnalysis2-22.3Evaluation of Various Safety Related Areas 2-42.4Hazards from Smaller Aircrafti 2-62.5Conclusion2-72.6References for Section2-7l-18 SBFSARABSTRACTResults are presented which verify the adequacy of thecontainment to resist the impact of an FB-111 type aircraft.Includedis a description of the dynamic forcing function, the elastic-dynamicanalysis, the elastic-plastic analysis, an estimate of reinforcementand liner strain and a verification of the punching shear capabilityof the containment.It is shown that there existsmechanism by which spilledfuel from the impacting aircraft can access theThe ensuingfire is, therefore, postulated to start in thevicinityexternal toenclosure and it is demonstrated that these externalfires do not, in any way, inhibit or handicap the safe shutdown cap-ability of the plant following the postulated crash.It is concluded, that under the aircraft impact, the containmentstructure is able to withstand postulated impact and that the consequencesof the aforementioned fire hazard is mitigated by the inherent designfeatures ofStation. | |||
1.0 STRUCTURAL ANALYSIS OFSTATION+2l-ldxFSARAIRCRAFT IMPACT1.1 IntroductionTheStation containment has been analyzed for the effects ofa-postulated impact by an FB-111 type aircraft with a speed atimpact of 200 mph.Based on the analyses performed;-theof the containment to withstand the postulated impact is verified.TheStation containment and enclosure building is describedin Section 3.8.1 of thePSAR. The FB-111 aircraft, the missilein the postulated73.5 feet long, has a wingspanoosition) of 70.0 feet and weighs 81.800 Dounds (See Reference 1).In order to perform the analyses,a force-time relationship isdeveloped from the mechanical properties of the impacting aircraft.An elastic dynamic analysis indicates that an elastic-plasticdynamic analysis is required to predict theresponse of thestructure.From this analysis of the structure,is madeof the strains experienced by the reinforcing bars and liner.Subsequently, an analysis is performed to verify the adequacy of thecontainment against punching shear and penetration.1.2 FORCING FUNCTION FOR IMPACTING AIRCRAFTThe time variation of the load on a rigid surface due to an impactingaircraft may be developed using the momentum principle.The governingequations which are used to determine thevariation of the forceexperienced by the target are (Reference 2): | |||
FSARwhereR(t) is the force acting on the target (positive for compression),is the extent of crushing at any time t as measured from theleading edge of nose of the missile,is the load required to crush the cross section of the missileat any distance n from the nose,(positive for compression)is the mass density per unit length of the missile as a functionof the distance from the nose.These equations are used to determine the two unknowns, the crushinglength,and the reaction, R(t), as functions of time.Theinformation required to determine these variables consists of theinitial impact velocity, weight or mass distribution and crushingload distribution of the aircraft.The first equation is integrated numerically to obtain the velocitytime history. The reaction force is then determined from the secondequation.Figureshows three views of the FB-111 aircraft. Figurethe one dimensional idealized model of the same aircraft. Figure 2bdescribes the weight distribution for an FB-111 with a total weightof 81,800 pounds.The sketch and the weight distribution are obtainedfrom Reference 1.The particular configuration used is essentiallythe same as that summarized on P. 1.3.3 of Reference 1 with the wingstores and wing useful load removed.This configuration is consistenttheof the FB-111 at Pease AFB. The value of 81,800 pounds is thel-2 FSARweight before the airplane has warmed up and taken off.flights the aircraft would fly a mission and return to Pease AFB withapproximately 10,000 pounds of fuel.On this basis, the landingweight would be approximately 59,000 pounds.For those missionswhen the aircraft is flown with wing tanks the maximum take-offweight ispounds. The FB-lllis not allowed to land withfuel in these wing tanks; therefore in all cases the maximum landingweight is 81,800 pounds.Thus, the 81,800 lbs weight of the FB-111 used in the impact analysiswas the fully loaded FB-111 without wing tanks.This weight isconservatively large for any configuration of the aircraft flyingout of Pease AFB, but it was used because it represented a maximumupper bound on the weight of the FB-111 in the landing pattern.The exact crushing load distribution foran PB-111 is not available.The crushing load distribution shown onis arrived at byscaling the known values for ais demonstratedin this report that the peak value of the reaction is relativelyinsensitive to reasonable variations ofthe crushing load.Figure 3 shows the reaction-time relationship for the FB-111 strikinga rigid wall at an impact velocity of 200 mph. The peak value of thereaction is 8.2 x pounds. This peak value occurs when the wingstructure is in the process of collapsing.This peak reflects thel-3 PC8.5 x8.2 xpounds7.1 xpoundsFSARmass in the wing structurefuselage in the vicinitythenoted that the cross-sectional area overlargerthe area of fuselagesecondaryof 4.2106 pounds (atthe vicinity of the engines.The determination of the sensitivity of theto the magnitudethe crushing load is investigated bytheforvalues of one-fifth and fivethis crushing load.Theseresults are shown in Figure 4.From Figure 4,peak values of thereactions are:The peak value of the reactionrelativelv insensitive to variationsin' the magnitude of the crushing load, and the scaled value of PCjudged to give accurate results.1.3Behavior of Containment1.3.1 Elastic Dynamic Analysis For the elastic dynamic analysis, the finite element methodwas chosen as the analytical method, and a computer programfor axisymmetric structures subjected to arbitrary static anddynamic loads was used.(See Reference 3 for the basis of themechanics of the program.) Damping was not considered. Thus,the predicted structural response is slightly larger than thatwhich does occur.l-4 FSARTo accomplish the analysis, several assumptions were made.They are as follows:i)Theis fixed at the base of the cylinder.ii)Impact loads are uniformly distributed over the loadingzones.iii)In the axisymmetric analysis (impact at apex of dome), theloading zone is a circle with a radius of 52.77 inches andan area of 8748.3 square inches.iv)In the asymmetric analysis (impact at springline), theloading zone is a square,93.53 inches on a side and8748.3 square inches in area.v)The stiffness of the reinforcing steel is neglected; onlythe gross concrete volume is considered.The modulus ofelasticity was taken as 3.0 xin., Poisson'sratio was taken as 0.15, and the weight density wastaken as 150 pcf.vi)The effect of the enclosure building is neglected. Itcan be shown that the enclosure absorbs approximately 4%of the energy of the impacting aircraft.The containment structure is modeled with axisymmetric conicalshell elements, a plot of this model is shown in Figure 5.Two impact positions, the apex of the dome and the springline,are considered. The impact at the dome is uniformlydistributed over the first seven (7) elements, and the impactat the springline is uniformly distributed over the six (6)elements nearest to the springline.By means of a half-rangecosine series, the load at the springline is confined to al-5 FSAR6.18' arc.(30) terms were used to represent thisFourier series which is shown, normalized to 1.0, in Figure 6.Experience with loadings similar to the loadings here, hasdemonstrated that twenty (20) terms of the series were foundto be too few and ninetyterms were found toresultsvery close to those generated by thirtyterms.Selected maximum results for the axisymmetric and asymmetricanalyses are given in Tablesand l-2, respectively. Thesemoments will cause cracking of the concrete and yielding oftheTherefore, an elastic-plastic dynamic analysis isrequired.1.3.2' Elastic-Plastic Dynamic Analysis The procedure followed for the elastic-plastic analysis ofthe response of the containment under aircraft impact followsthat of(Reference 4). In this procedure, knowing theload-time relationship, the first natural frequency of thatpart of the structure participating in the energy absorption,and the allowable ductility ratio (defined as the ratio of themaximum deflection to the deflection at yield), the ratioof the maximum value of the load-timeto themaximum value of the resistance function can be determined. This1-6 SBFSARcan then be compared with the actual estimated maximum valuesof the load-time relationship and resistance function.The force-time relationship, given in Figure 3 is approximatedby a triangular load-time curve with the same total impulseand peak force.This ideal and the actual force-time relation-ships are compared in Figure 7 .It is assumed that a circularregion of radius "a" will participate in the energy absorption.The natural frequency, associated with this participatingregion, is estimated on the basis of the first naturalfrequency of a flat circular plate of radius "a" clamped atthe edges.The assumption of clamped edges, in that it givesa smaller period for the first natural frequency than in theactual case, is a conservative simplification. This followsbecause, in general the value of the maximum allowable forcingfunction decreases as the first natural period decreases (Ref. 4,p. 78, Figure 2.26).Conversely, ignoring the curvature isnon-conservative in that it gives an estimate*of the periodwhich is larger than the actual case.For small values of theradius "a", the curvature effect is minimal.All calculations are based upon thedome sectionconfiguration.The first natural frequency of a flat circularplate, clamped at the edge is:PX.17whereis therigidity and M is the mass density per unitsurface area (See, for example, Ref. 5).l-7 FSARthethick concrete plate with a Young's modulus ofpsi and a unit weight of 150 pounds per cubic foot,period is:sectioncracked section"a" in feet T15.94 x12.86 xUsing Fig, 2.26 of Reference 4the ratioas afunction of the radius of the participating material of thecontainment,can be determined for various values ofductility ratio.For the purpose of this investigation, two (2) ductilityratios, 3 and 10 are used. For plates and shells, the lowervalue is conservative, the larger value reasonable. Theresults of the calculations are shown in Table l-3 and Figure8.Although the range of Fig. 2.26 of Reference 4 islimited to aof 20, it can be observed that for aductility ratio greater than two and of 20, isgreater than unity. Therefore, the allowable peak force,F, can be than the maximum value of the resistance, Rm.1.3.3 Resistance FunctionIn the vicinity of the impact region, the response of thestructure is assumed to have the characteristics shown inFigureFor values of the force less than Rm, the displacements arelimited in magnitude even though the response may be inelastic.As the load reaches the valuethe deformations are ablel-8For3xthe 2+=FSARto become arbitrarily large, i.e.,the collapse load has beenreached.The collapse load for a concentrated load on acurved shell is not readily accessible.As a conservativeestimate, the collapse load for a flat plate with reinforcementthe same as the dome is used to estimate the collapse loadfor the shell..Expecting the yield line formation shown in Figureobservationsuggests that the clamped boundary condition case should beused. The value of the collapse load, Rm, is then (Referencewhereis the ultimate moment capacity and the notation + andrefers to the outside and inside reinforcement respectively.The ultimate moment capacities and collapse loads of thecontainment are:dome= 643 k-ft. /ft.651 k-ft./ft.springline= 1,235 k-ft./ftM-643 k-ft./ftAt the dome, the collapse load and peak load are approximatelyequal.However, from Figure 8 , the dynamic effect allowsthe structure to withstand loads in excess of the capacity.From Figurethe allowable load is 10% larger than theresistance or collapse load.Therefore,the apex will notl-9 FSARcollapse.Since the maximum load,less than thecapacity of the dome in the springline,collapse willnot occur at the springline.The dome will not collapse, under the applied load.1.3.4 Estimation of Rebar and Liner StrainsWhile plastic analysis techniques are useful for finding collapseloads, they cannot be directly used to find the strains anddisplacements corresponding to collapse loads.However, a procedure making use of the ductility ratio can beused to approximate the maximum strains in the structuresubject to dynamic loading when nonlinear material behavioris encountered.This procedure is described below.A typical load-displacement curve for reinforced concretesection is shown in Figure 10.This curve is linear up to theload causing crackingafter which a straight line ofsomewhat flatter slope is obtained until the loadisreached which causes yielding of the steel.Any increase in load beyondcauses the displacement toincreasedisproportionately.Further increase in load causesextensive displacements to occur,resulting in eventual collapse.This actual behavior of the structure was idealized as shown inFigureand was used for the elastic-plastic dynamic analysispreviously discussed.Thiscurve represents theresistance function of the structure.l-10 Y60 0.002FSARThe ductilityreferred to in the elastic-plasticdynamic analysis represents the ratio of the maximum displacementof the structure to the deflection established as yieldforthe structure.While it is recognized that the ductility ratio is not an exactmeasure of the maximum strain at a particular point of thestructure, it can be used as an approximation because theat yield in the actual structure is very nearly the straincorresponding to yield for the idealized structure.The procedure used herein is based on the peak of the actualforcing function resulting from the-aircraft impact, the durationof loading, theresistance function for the structureand the first natural period of the responding part of thestructure.By using the above known quantities, the correspondingductility ratio for the structure may be determined.For a peak in the forcing function of and ain the resistance function of 8,130 k, the maximum ductility ratiofor all ratios of is Fig. 2-26, Ref. 2).Thus, regardless of the natural period of the responding part ofthe structure, the largest displacement that will occur under theaircraft impact loading is the same as that to yieldfor the idealized structure.The yield strain for the reinforcing steel is SBFSARIf it is assumed that thecorresponding to yieldforthe idealized structure is 50% larger than this (actuallymuchless than this),, then an upper bound for the strain in thereinforcing steel will be:x 1.5 x 0.002 in/in =in/inSince the liner and the tension reinforcing steel are only severalinches apart in a 42" thick containment dome, they will bestrained to nearly the same values.Hence, there will be nopossibility of impairing the leak tight integrity of the liner.1.4 Response of the Enclosure Building During the early stages of the impact process, the enclosure buildingwill deform until it comes into contact with the containment. Theenclosure building must deflect five feet in order to come intocontact with the containment dome.Such a deformation will involvean inelastic response.This inelastic response will involve bothflexure and shear.The 15" thick enclosure building is reinforced withboth ways and both faces.The collapse load is 635k.The allowable shear load will depend upon the shear area over whichthe transverse shear stress acts. This shear area is determined bymultiplying the average shear periphery by the effective depth ofthe shell. The average shear periphery is determined by a contourwhich is at a distance of one-half the effective depth away from thecontour of the contact area (Figure 12 to 21 show theimpact area and shear periphery associated with various locations1-12 FSARalong the aircraft and for the effective depths of the enclosurebuilding (9") and containment (37").The reaction as a function of the cross section being crushed isdetermined from the reaction-time and crushing distance relationshipand is shown in Figure 22.From this information, it is possible to examine the effect of theaircraft impact on the enclosure building as a function of thedistance being crushed.Figure 23 shows the average shear stresson the enclosure as a function of distance being crushed.Forexample, using a shear strength of 4.25the enclosure buildingwill fail by shear when the aircraft is crushing at 7.25 feet.Alsoshown on Figure 23 is the reaction as a function of the distance beingcrushed.For a collapse load ofthe enclosure building willcollapse when the aircraft is crushing at 9.75 feet.It wouldappear that, usingas a shear strength,the enclosurewould fail by shear before collapse, however, the two eventswould occur at a time difference of 0.0086 sec. Any increase inactual shear strength abovewould increase the possibilityofand collapse happening simultaneously. Asbedomonstrated in Section 1.5, the actual shear strength can varyconsiderably above a value ofNo clear conclusion canbe drawn as to whether punch through or collapse occurs first. Basedon the above discussion, the failure of the enclosure building willinvolve both extensive shear and flexure damage and it will deformuntil it comes into contact with the containment.1-13 FSAR1.5 Shear Capability of the Containment The enclosure building will deform until it comes into contactthe containment dome.The dome will then resist the impact forceand experience transverse shear stress in the vicinity of the impactarea. The maximum average shear stress is determined by defining ashear perimeter and thickness over which the impact force is acting.Figure 24 describes the procedure by which the shear perimeter forthe maximum average shear stress acting on the containment dome isdetermined.The shear perimeter for the containment is at adistance(effective depth of enclosure) + ( effective depth of containment 2away from theof the impact area.The values of the shear perimeter for various cross sections of theaircraft are given in Table l-4.Also shown are the shear area,impact force and average shear stress for the containment building.The values of average shear stress as a function of the cross sectioncrushed is shown in Figure 25. The shear stress is given interms of psi andThe maximum value of the average shear stressoccurs when the aircraft is crushing at a distance of 35 feet fromthe nose. The value of this maximum average shear stress is 229 psiorVarious shear strengths have been proposed.A tabulation of theseshear strengths, for parameters similar to the aircraft and structureunder discussion is shown in Table l-5.It is seen that the maximumnominal shear stress ofis less than all the otherproposed values except the conservative value ofas proposed by the1-14 G1.01-15B2.570.454dmxeVWKFSARXI-Committee 326.Hence, it is concluded the the containmentwill not fail by punch through.1.6 Requirements to Prevent Perforation The velocity of the engines as they impact on the enclosure buildingand containment is 250 fps.The FB-111 has two Pratt Whitney(Military designationjet turbo fan engines with an outside diameter of 50.22inches.Each engine has a dry weight of 4,121 pounds (Ref. 1).The thickness of the dome required for no performation was determinedusing procedures reported in Reference 7.The pertinent nomenclature is :penetration thickness for infinitely thick slab (inches)perforation thickness for reinforced concrete (inches)diameter of missile (inches)velocity of impact (feet per second)weight of missile180ultimate compression strength of concrete (psi) | |||
FSARSince a jet engine is not completely solid (thin shells for torquetransmission, blades for fan, compressor and turbine, burner cans forcombustion) the engine was assumed to behave similarly to a hollowpipe missile.For a fan-jet, the outside diameter is slightly larger than the gasgenerator.Two values of dm (the diameter of the gas generator)were used, SO.23 inches and 40 inches. The results are:dm (inches)21.822.8These values can be compared with the dome thickness of 42 inches.From these calculations,can be concluded that there will be noperforation.1.7 ConclusionsFrom the above results of the analysis of theStationContainment,the following conclusions can be made:1.The enclosure building will fail and will come into contact withthe containment building.The mode of failure will not be byshear or flexure alone, but will involve both types ofdamage.2.The containment building will not fail.Thestrength willprevent collapse.The shear strength will prevent.punchThere will be permanent damage to the structure, but the extentof this damage will not be sufficient to cause loss of theintegrity of the building.l-16 FSAR3.The linerinelastic, will be sufficiently smallso that tearing of the liner will not occur.4.The engines will not perforate the containment.These conclusions can be made even though the above analysis wasperformed with considerableThe conservative aspectsof the analysis are:1.The reaction-time relationship was determined for impact on a rigidtarget. A realistic, flexible target would reduce the peak valueof the reaction.2.Normal impact was assumed.Any impact angle other thanreducesthe impact forceand increase the area over which the impactforce acts.3. The arcing effect of the doubly-curved dome was ignored. Archingincreases the collapse and punching load capacities.4.The shear stresses can be computed more accurately using theeffective forceduring the time necessary for thestructure to respond rather than the peak instantaneous force.The peak instantaneous force will give larger shear stresses thanthe effective force.5.The actual concrete compression strength will be larger than thespecified strength of 3,000 psi.This would result in a largervalue for the shear strength.6. A conservative estimate of the shear periphery used to calculateshear areas and shear strengths wasThe1-17 FSARfailure cone was assumed to be through the containment only andnot through the combined thicknesses of the containment andenclosure building,The latter would be more accurate.The integrity of the containment buildingnot be impaired in theoccurrence of the postulated aircraft impact. | |||
==1.8 REFERENCES== | |||
FOR SECTION 1.01."FB-111 Unit Inertia Data, "General Dynamics, Fort Worth Division,Report FZS-12-6010, Revision "A", January, 1968.2.Riera, J.O., "On the Stress Analysis of Structures Subjected to AircraftImpact Forces" Nuclear Engineering and Design, North Holland PublishingCompany, Amsterdam, Holland, 8p. 415-426.3.Ghosh, S., and Wilson, E., "Dynamic Stress Analysis of AxisymmetricStructures Under Arbitrary Loading", University of California,Berkeley, CA., Revised Sept., 1975.4.Biggs, J. M., Introduction to Structural Dynamics, McGraw-Hill, Inc.,1964, pps. 69-84.5. Meiorovitch, Analytical Methods in Vibrations, The Macmillan Company,1967, p. 183.6.Save and Massonnet, Plastic Analysis and Design of Plates, Shells and Disks, North Holland, 1972, p. 245.7.Kennedy, Effects of an Aircraft Crash Into a Concrete Reactor ContainmentBuilding.HolmesNarver, Inc., July, 1966.1-18 | |||
-478-478FSARTABLE l-lMAXIMUM RESPONSEANALYSIS(IMPACT AT DOME)MeridionalCircumferential Element 36 is elementabove springline.FSARTABLE 1-2RESPONSEASYMMETRIC ANALYSIS(IMPACT AT SPRINGLINE)Meridional-1139Ft-K/FtCircumferential-1309Meridional383Circumferential442Meridional-1148.Ft-K/FtCircumferential1350Meridional*378Circumferential431Element 37 is element immediately below springline. | |||
SectionTABLE l-3ALLOWABLEFORCE, MAXIM?? RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATING TARGET MATERIAL RADII31.121.2331.151.1231.201.3331.251.47Participating Radius; since this is notdefined, a range of values isincluded.** By observation, Pigure 2.26,"Introduction to StructuralRiggs-3( 1.00 x 10-29.03 x1.61 x 104.92 x 10-2T4.01 x 10-33.61 x 10-26.42 x 10-24a12162024322.51 xCracked Section41.24x137.1a4.92x10-334.2121.12x10-215.2161.99x10-2a.53-210203.11x105.43-210244.48x3.8310286.09x2.83-210327.96x102.131011.101.201.101.301.171.361.231.471.251.70170.042.418.810.6 1-4AVERAGE SHEAR STRESSLocationShear Perimeterft.ft.Shear AreaReactionpoundsAverage ShearStresspsi*If the wings were assumed to have sheared-off at the time that the aircraft were crushing at this locationthe shear perimeter and reaction would-be reduced to 64.6 ft. andrespectively. The average shearstress then becomes 198 psi.the horizontal and vertical stabilizers were assumed to have sheared-off at the time that the aircraftwere crushing at this location the shear perimeter and reaction would be reduced to 42.1 ft. andrespectively. The average shear stress then becomes 209 psi.average shear stress for the case were the crushing strength is reduced by 5 is 245 psi.32.614,47437.016,42841.818,55950.222,28899.844,31145.520,20249.221,84449.221,84415193541505889229178686,00032 Ultimate Shear StrengthpsiUltimate Shear Strength71765560752752552344539138336335129221913.111.911.089.629.589.557.146.996.626.415.334.00SBFSARTABLE l-5COMPARISON OF ULTIMATE SHEAR STRENGTH CAPACITY*equation 5-2,equation 5-1,=equation S-10,=equation 5-5,=equation 5-2,= 1equation 5-3,=equation 5-1,= 1equation S-10,= 1equation 5-5,1equationequationequation 5-6equation 5-9,326shear stress at distanced/2 from periphery = 1*"The Shear Strength of Reinforced Concrete Member-Slabs",JointTask Committee426, Journal of the Structural Division, ASCE, Aug., 1974.c = 93"= 3,000 psip = 0.0099d37"Y60,000 psi**Adjusted for circular region,evaluated at d/2 away from periphery. | |||
10 FT 3 INI.133FT., II IN.STA270.50STATICGROUND LINESTA562.97 704020Figure 2B E I G H TSB 1 2FSAR73.5---FigureI I I60040 8622FSAR TIMESECONDSFIGURE 3REACTION-TIME RELATIONSHIP 5PFSARP denotes the scale crushing load used in the calculation.and5 denotes that one-fifth and five time the crushing loadused,'respectively.1086T I M ESECONDSFIGURE 4Reaction-Time Relationship for FB-111 with impact velocities of 200 mph. | |||
SB 1 & 2FSARFIGURE 5FINITE ELDIENT MODEL FSARNO.3S T A T I O NFIGURE.6FOURIER SERIES REPRESENTATION OF SPRINGLINE LOADING 00.050.100 . 1 50.200.250.30FIGURE 7 ACTUAL AND IDEAL REACTION TIME RELATIONSHIP MATERIAL,FSARFIGURE 8ALLOWABLE MAXIMUM FORCE, MAXIMUM RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATION TARGET MATERIAL RADII SBFIGUREBEHAVIOR ANDLINE CONFIGURATION FSARFIGURE 10.LOAD-DISPLACEMENT CURVE FOR REINFORCED CONCRETE SB 1FSAR | |||
- 15.2 ft.30.2 ft.Shear PerimeterSBFSARFigure 13, Impact Area and Shear Perimeter at 8.5 Feet From Nose SBShear PerimeterEnclosure17.8 ft.Containment31.8 ft.Figure 14, Impact Area and Shear Perimeter at 9.9 feet From Nose SBShear Perimeter- -ft.Containment 32.6 ft.FigureImpact Area and Shear Perimeter at 15 Feet From Nose FSAR\\IShear PerimeterContainment37.0 ft.Figure 16, Impact Area and Shear Perimeter at 19.0 Feet From Nose Shear PerimeterContainment37 ft.FSARFigure 17, Impact Area and Shear Perimeter at 27 Feet From Nose FigureImpact Area and Shear Perimeter at 35 Feet from NoseShear Perimeter'Containment 50.2 Ft.SBFSAR | |||
...Containment - 99 8 ftShear Perimeterm.MIN********.*1.Figure 19, Impact Area and Shear Perimeter at 41.0 Feet From Nose Shear PerimeterContainmentII43.2 ft.SB2FSARFigure 20, Impact Area and Shear Perimeter at 50.0 Feet From Nose Shear PerimeterContainment 49.2 ft.Figure 21Impact Area and Shear Perimeter at 58.0 Feet From NoseFSAR IDISTANCEFEET1010304050602FIGURE 22, REACTION-CRUSHING LOCATION RELATIONSHIP JPSI6.005.0025010012345671750DISTANCE CRUSHED-FT.Figure 23 Average Shear Stress-Distance Crushed and Reaction Distance CrushedRelationship for the Enclosure Building. | |||
2Effective Shear Area24 SCHEMATIC FORSHEAR 25STRESS-DISTANCE CRUSHED RELATIONSHIP FOR CONTAINMENTDISTANCE CRUSHED229 PSI FSAR2.0FIRE HAZARD ANALYSIS OFSTATION CONTAINMENTFOR AIRCRAFT IMPACTA highly unlikely chain of adverse events is postulated in thefollowing manner:An FB-111 with a weight of 81,800 lbs and initial speed of 200mph impacts on one of the two double containment complexes of thebrook plant.The enclosure building deforms locally under the initialimpact,and the local deformation continues with little to no perforationuntil the enclosure building comes into contact with the containmentbuilding.This fact, plus the fact that if any penetration should occurit would be only the nose of the aircraft, will preclude the spillingof significant amounts of fuel into thespace. Thespacecontains no equipment,and all penetrations both mechanical and electricalare isolated from missiles and fuel by reinforced concrete slabs,Theenclosure building acts as a barrier and directs the spilled fuel to theexterior area near the enclosure building.The following effects werethen studied:Possible production of combustible vapor, its promptignition and the ensuing pressure pulse, and thepossibility that the combustible vapor may be suckedinto the plant areas and be cause for delayed ignitionor toxic atmosphere in habitability systems.The fuel spilled and its transport to various areas ofthe plant. An ignition is then postulated, and theeffect of the ensuing fire studied in order to evaluate2-l FSARthe safe shutdown capability of the plant.The effect of smoke and/or toxic gases as may be generatedby the fire, with particular reference to control roomhabitability.The effects as detailed in (1) and (3) for all smaller air-craft.2.1COMBUSTIBLE VAPOR PRODUCTION The FB-111 carries approximately 32,000 lbs of type JP-4 fuel. Asindicated in Reference 1, the process of combustible vapor production isas follows:the crashing aircraft drags along the ground in a relativelyslow deceleration (0.4 g) which lasts for a 'long' time (20and thefuel issuing from the wing after some postulated leakage mechanism isatomized to mist by the air as a result of its velocity relative to air.For the direct impact considered here,the decelerations are very high(peak value of 29 g) and of very 'short' duration (0.3 sec.).The atom-izing process under these conditions is not significant.It is, there-fore, concluded that the combustible vapor production and the associatedhazards can be considered to be mitigated.2.2FIRE ANALYSISVarious spill mechanisms are postulated either on the roofs or onthe ground adjacent to the containment structure:The various roof areas adjacent to the containment enclosurewith their elevation approximate areas, etc., are detailedin Table 2-1.As stated in PSAR Section 2.4, most of theseroofs have parapets, and the roof drainage systems aredesigned to drain at least 3 inches per hour rain. It is2-2 FSARnoted further that 1 inch of fuel takes 10 minutes toUsing the minimum area in Table 2-1, and acatastrophic instantaneous mode of fuel release, themaximum expected duration of the fire is 17.9 minutes.For ground areas adjacent to the containment, there isapproximately 1.5 acres of land, the total drainage ofwhich is approximately 6 cfs.The spreading of the fuelover this area and the adequate drainage would result ina film fire with width comparable to the roughness of thepavement, e.g.,inch.The resulting fire would lastonly for 1 minute at the most.The mechanism of fire propagation was examined. No flamm-able material is normally expected to be present next tothe containment which can serve as the propagator of thefire. The range of the fire has very conservativelyestimated to be 200 ft. from its point of origin.Smoke is postulated to be traveling from this centre firelocation carried by the wind.Its effect on the habitabilitysystems was then studied.The possible hazard of fuel getting into the PAB Buildingthrough the vent stack is considered remote due to the follow-ing reasons:The mechanism is improbable.The entering fuel will be drained off at the base ofthe vertical stack, just as rainwater would be.The possible hazard of fuel getting into the main steam linetunnels through the side vent openingsconsidered notprobable since the vent openings are above grade.2-3 FSAR2.3 EVALUATION OF VARIOUS SAFETY RELATED AREASThe various intake points to the safety related areas and theirdescription8 are detailed in Table 2-2,including the missile shieldswhen applicable, under the accident conditions detailed in Subsection2.3. All buildings other than the control room and the PAB residualheat removal area are either not needed for safe shutdown or are redun-dant.However, the conservative analysis below includes the reactionof these areas to the postulated fire.(a) Control Room There is no mechanism for the fire to endanger the habitabilityof the control room, since the split intake vents are at adistance of at least 300 ft. from the containment; therefore,it is beyond the reach of the direct fire. However, in theremote event that the fire finds its way into the intakestructure, the temperature and smoke sensors will sense itthe intake opening will be closed. Under theseconditions, the other intake will be used for ventilating thecontrol rooms.Primary Auxiliary Building (PAB) The air intake is located on the east wall of the primaryauxiliary building at an elevation ofThe area infront of the intake has the containment enclosure roofelevation ofand the east wall of the PAB faces thecontainment and the fuel storage building.There may be afire lasting 12.5 minutes at most on the roof of thecontainment enclosure area, a part of which may be injectedinto theair intake, as its height is 3 ft. above the2-4 FSARroof of containment enclosure area.The inside of thePAB has roll-type filters after the intake and heatingcoil panels after the filter.Therefore,the flame andthe hot gases would have to penetrate the filter and thecoils before reaching the fans.As indicated in Subsection 2.2, the roof surface of thecontainment enclosure area will be finished smooth andwith proper drainage to drain off the spilled fuel quickly.Smoke and heat sensors will be located at the air inlet sothat on a signal from them the operator can stop the fans.Diesel Generator BuildingThe diesel generator building intakes are on opposite sidesof the building and are located at least 180 ft. from thecontainment structures.It is considered improbable thatthe spilled fuel will find its way underneath one of theseintakes.Furthermore,the intakes are 28.5' above gradelevel, and it is unlikely that the fire will rise to thatheight.In addition, one of the intakes is shielded bythe diesel generator building and it is thus not consideredcredible that the fire could reach that intake.Althoughit may be postulated that the hot gas from thepoint may cause momentary oxygen starvation ofgenerator, the shielded intake will ensure theother diesel generator and of one train.Service Water Building direct intakeone dieselintegrity ofThe intake for the service water building is approximately280 ft. from the containment'and should be out of reach ofthe postulated fire.Furthermore,the air intake is located2-5 FSARin the east wall of the building.Consequently, thebuilding serves as a shield for the spilled fuel flow.Additionally, there is a missile shield in front of thestructure, which should inhibit any possible fuel flowand subsequent fire.The fire effects are, therefore,considered minimal. However, a minute amount of hot gasmay enter the facility, but since the pumps are locatedat the west end of the building, it will not criticallythreaten their operation due to rise of temperature.Vent StackThe vent stack is not a safety related item and, as in-dicated in Subsection 2.2, it does not furnish a significantpathway for the fuel to get into the primary auxiliary build-ing. This mechanism of fire propagation is, therefore, con-sidered incredible.Cable Spreading, Battery Room, Switch Gear Room and Cable Tunnel The air intake for cable spreading, battery room, switch gearroom and cable tunnel areas is through the mechanical equip-ment room of the diesel generator building, and the varioussafety aspects discussed for the diesel generator room holdfor this case.2.4HAZARDS FROM SMALLER AIRCRAFTThe smaller plane crashes were examined for the various areas, asdetailed in Subsections 2.2 and 2.3. The fuel in general may be JP-1,kerosene and JP-4.Since the fuel carrying capacity for all these planesis smaller than that of FB-111, and their burning temperatures are of thesame order of magnitude, it was concluded that the effect would be envelopedby those in the case of FB-111.2-6 FSARCONCLUSIONS In view of the results in Subsectionsandit was con-cluded that the hazard toStation from direct fire after thepostulated crash of an FB-111 or smaller aircrafts on the containmentrepresents only very minimal potential hazard to the plant.The presentdesign of the plant has inherent safety features so that the consequenceof this minimal hazard is mitigated.REFERENCES FOR SECTION 21.Appraisal of Fire Effects From Aircraft Crash at Zion PowerReactor Facility, I. Irving Pinkel,Consultant, Atomic EnergyCommission, July 17, 1972.Flammability Characteristics of Combustible Gases and Vapors,Bulletin 627, U. S. Bureau of Mines, 1965, Michael Zabetakis. | |||
BUILDINGSROOFAREA(SQ.FT.)ELEVATIONREMARKSCONTAINMENT ENCLOSURE4,10053'WITH PARAPETEMERGENCYFEEDWATERPUMPBLDG.3,00047'WITH PARAPETFUEL STORAGE BUILDING9,20084'WITH PARAPETPRIMARYAUXILIARYBUILDING8,14481'WITH PARAPETPAB Filter Room2,856108'WITH PARAPETTABLE 2-lROOF DESCRIPTIONSNOTE:GRADE ELEVATION 20' TABLEVENTILATION SYSTEM DESCRIPTIONS OF THE BUILDING SURROUNDING THE CONTAINMENT .,SHEET 1 OFBUILDINGBUILDINGSURFACEFACING THE CONT.LOCATIONS OF THEINTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMCONT.WALLELEVATIONDieselGen.South wallSouthWall200 ft.28.5ft.above gr.Other Bldg.at 40'dist..Ventilationair;notnecessaryforsafeshutdown.NorthWall240 ft.(thruroof)28.5 ft.aboveOther Bldg.at40PABEast wallEastWall20 ft.3aboveadjacentroof.Shielded bythe Cont.F.Stg.Bldg.Normalventilationair;only RHRpump area safeshutdownrelated.NorthWall95ft.(thruroof)29ft.above gr.thickshield.Ventilationairtosafety relatedmary component cool,ing water pump areaand Boron injectionpump area.EmergencyFeedwaterPump Bldg.South WallNorthWall30 ft.(thruroof)18ft.above gr.2'thickconcretemissileshieldVentilationairtothe emergencywater pump area. | |||
TABLE 2-2 (CONT.)SHEET 1 OF 2BUILDINGBUILDINGSURFACEFACING THE CONT.LOCATION OFTHE INTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMELEVATIONCONT.WALLServiceWaterPumpHouseWest WallEastWall290ft.(throof)ru45 ft.above2'thickmissileshield.Ventilationairtotheservice waterpump house.WestWall180ft.13.5above2'thickmissileshield.Air intake to theelectricalareas.ControlRoomComputerRoomSouth 6EastWallsRemoteIntakePorts300ft.least)At gr.levelCoveredwithgrating.Ventilationairtothe habitable areasof the control andcomputer room. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-1 APPENDIX 2Q EAB AND LPZ SHORT TERM ACCIDENT DIFFUSION ESTIMATES FOR AST 2Q.1 OBJECTIVE Conservative values of atmospheric diffusion at the site boundary (EAB) and the low population zone (LPZ) were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2Q.2 METHODOLOGY The methodology used for this calculation is consistent with Regulatory Guide 1.145 as implemented by the PAVAN computer code (Reference 2). Using joint frequency distributions of wind direction and wind speed by atmospheric stability, the PAVAN computer code provides relative air concentration (CHI/Q) values as functions of direction for various time periods at the site boundary and LPZ. Three procedures for calculation of CHI/Qs are utilized for the site boundary and LPZ; a direction-dependent approach, a direction-independent approach, and an overall site CHI/Q approach. The CHI/Q calculations are based on the theory that material released to the atmosphere will be normally distributed (Gaussian) about the plume centerline. A straight-line trajectory is assumed between the point of release and all distances for which CHI/Q values are calculated. The theory and implementing equations employed by the PAVAN computer code are documented in Reference 2. 2Q.3 CALCULATIONS/PAVAN COMPUTER CODE INPUT DATA The boundary distance used in each of the 16 downwind directions from the site was set to 914 m. The LPZ boundary distance was set to 2,011 m. All of the releases were considered ground level releases because the highest possible release elevation is from the plant stack at 185 ft above plant grade. From Section 1.3.2 to Reference 1, a release is only considered a stack release if the release point is at a level higher than two and one-half times the height of adjacent solid structures. For the Seabrook plant, the elevation of the top of the containment is 199.25 ft. Therefore, the highest possible release point is not 2.5 times higher than the adjacent containment buildings, and thus all releases were considered ground level releases. As such, the release height was set equal to 10.0 meters as required by Table 3.1 of Reference 2. The building area used for the building wake term was 2,416 m2. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-2 The tower height at which the wind speeds were measured is 10.05 m above plant grade. The windspeed units are given in miles per hour, therefore the PAVAN variable UCOR was set equal to 101 to convert the windspeeds to meters per second as described in Table 3.1 of Reference 2. The maximum windspeed in each windspeed category was chosen to match the raw joint frequency distribution data, which conforms to the windspeed bins in Table 1 of Reference 3. 2Q.4 RESULTS PAVAN computer runs for the EAB and LPZ boundary distances were performed using the data discussed previously. Per Section 4 of Reference 1, the maximum CHI/Q for each distance was determined and compared to the 5% overall site value for the boundary under consideration. For dose calculations, the most limiting 2 hour CHI/Qs were combined with the worst 2 hour EAB doses to maximize calculated EAB doses (conservative approach). The maximum EAB and LPZ CHI/Qs that resulted from this comparison are provided in the table below: Offsite Boundary /Q Factors for Analysis EventsTime Period EAB /Q (sec/m3)LPZ /Q (sec/m3) 0-2 hours 3.17E-041.54E-04 0-8 hours 2.08E-048.63E-05 8-24 hours 1.68E-046.46E-05 1-4 days 1.06E-043.45E-05 4-30 days 5.51E-051.40E-05 2Q.5 REFERENCES 1. USNRC Regulatory Guide 1.145, "Atmospheric Dispersion Models for Potential Accident Consequence Assessments at Nuclear Power Plants," Revision 1, November 1982, (Reissued February 1983 to correct page 1.145-7). 2. NUREG/CR-2858, "PAVAN: An Atmospheric Dispersion Program for Evaluating Design Basis Accidental Releases of Radioactive Materials from Nuclear Power Stations," November 1982. 3. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-1 APPENDIX 2R SHORT-TERM (ACCIDENT) DIFFUSION FOR THE CONTROL ROOM 2R.1 OBJECTIVE Conservative values of atmospheric diffusion to the Control Room were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2R.2 METHODOLOGY The ARCON96 computer code is used by the USNRC staff to review licensee submittals relating to control room habitability (Reference 1). Therefore, the ARCON96 computer code was used to determine the relative concentrations (CHI/Qs) for the control room air intakes and inleakage locations. The ARCON96 computer code uses hourly meteorological data for estimating dispersion in the vicinity of buildings to calculate relative concentrations at control room air intakes that would be exceeded no more than five percent of the time. These concentrations are calculated for averaging periods ranging from one hour to 30 days in duration. The theory and implementing equations employed by the ARCON96 computer code are documented in Reference 1. 2R.3 CALCULATIONS/ARCON COMPUTER CODE INPUT DATA Five years of meteorological data (1998-2002) were used for the ARCON96 computer code runs. The percentage of valid data over this time period was 98.8% which exceeds the minimum value of 90% data recovery specified in Reference 2. A number of various release-receptor combinations were considered for the control room CHI/Qs. These different cases were considered to determine the limiting release-receptor combinations for the various events. The case matrix for these combinations is provided in Table 2R-2. The distance and direction inputs for the ARCON96 runs may be found in Table 2R-1. The distances were converted from feet to meters with a factor of 0.3048 m/ft. The distances in meters were then rounded down to the nearest tenth for conservatism. The elevation difference term was set equal to zero for each case since all elevation points are taken with respect to the same datum. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-2 The lower and upper measurement heights for the meteorological data were entered as 10.05 m and 60.66 m, respectively, for each case. The mph option was selected for the windspeed units. A ground level release was chosen for each scenario since none of the release points are 2.5 times taller than the closest solid structure as called out in Section 3.2.2 of Reference 3 for stack releases. The top of the containment structure is at an elevation of 199.25 ft. The highest release point is from the top of the plant stack at an elevation of 185 ft., which is not 2.5 times higher than the nearby containment structure. The vertical velocity, stack flow, and stack radius terms were all set equal to zero since each case is a ground level release. The vent release option was not selected for any of the scenarios. The actual release height was used in the cases. No credit was taken for effective release height due to plume rise; therefore, for the releases from the stacks, the release elevations were set equal to the stack top elevation. The release heights were taken as the release elevations less the plant grade elevation of 19 ft. The only cases in this analysis that take credit for the building wake effect are the scenarios where the release is from the containment building, the tank farm, or the waste processing building. Some of the other scenarios have buildings between the release and receptor points, but for these cases the building wake was not credited for the sake of conservatism. Not crediting wakes was accomplished by setting the building area term equal to 0.01 m2 as stated in Table A-2 of Reference 3. The first building area used is a conservatively determined containment cross sectional area. The area is calculated as the sum of the cross sectional areas created by the cylindrical portion of the containment structure above the highest nearby roof and the hemispherical area of the dome. The width used is equal to the diameter of the containment structure. The height of the cylindrical portion is taken as the distance between the top of the cylinder portion of the containment structure (represented by the spring line elevation) and the primary auxiliary building roof elevation. The radius of the hemispherical dome is taken as one half of the calculated diameter. The containment area was determined to be 1,506 m2. The second building area is calculated as the product of the minimum roof height of the waste processing building and tank farm and one half the width of the waste processing building and tank farm. The minimum roof height and one half of the width are used for conservatism. This building area was determined to be 337 m2. All of the default values in the ARCON96 code were unchanged from the code default values with the following exceptions. Table A-2 of Reference 3 suggests use of a value of 0.2 for the Surface Roughness Length, and use of a value of 4.3 for the Averaging Sector Width Constant. These two changes were made for each case. The minimum wind speed was left at 0.5 m/s per the guidance instruction in Table A-2 of Reference 3. | |||
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-3 2R.4 RESULTS ARCON96 computer runs for the various release points and control room intake locations were performed using the data discussed previously. Per Reference 3, the 95th percentile CHI/Q values were determined. The resulting CHI/Qs are listed in Table 2R-2. 2R.5 REFERENCES 1. NUREG/CR-6331 PNL-10521, "Atmospheric Relative Concentrations in Building Wakes," May 1995, with Errata dated July 1997. 2. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. 3. USNRC Regulatory Guide 1.194, "Atmospheric Relative Concentrations for Control Room Radiological Habitability Assessments at Nuclear Power Plants," June 2003.}} | |||
Revision as of 10:24, 19 May 2018
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UPDATED FSARAPPENDIX 2LGEOLOGIC INVESTIGATION OF SOILS AND THE BEDROCK SURFACE ATUNIT 2 CONTAINMENT SITE.STATIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
GEOLOGIC INVESTIGATIONSofSOILS AND THE BEDROCK SURFACEat2SITESTATIONPUBLIC SERVICE COMPANY OF NEW HAMPSHIRENEW HAMPSHIREOctober 24, 1974 CONTENTS1.Purpose of I nvc stigations2.Borings Investigationsto Boring3.Trench Excavations4.Bedrock* Exposed in TrenchesA.FaultingB.Jointing5.Unconsolidated Glacial Deposits6.ConclusionsFigure 1Public Service Company of NewSite SurveyFigure 2Geologic Map Unit 2 TrenchesFigure 3Soils ProfilesUnit 2 TrenchesAppendix IBoring Log BoringAppendix IIGeotechnical Report, Reactor BoringsGeotechnical Engineers, Inc.Page12334456 GeologicalofSoils and the Bedrock SurfaceUnit 2 Containment SiteStationNew HampshireAugust and early September, 1974, four trenchesin length were excavated to bedrock on anconfiguration acrossthe area of the Unit 2 containment site at theStation,Hampshire.The bedrock in the floor of these trenches is gneissoid quartzdiorite of the pluton, which is commonly fractured atthan 3* intervals in this area by an intersecting pattern ofangle and low-angle joints. The most prominent and continuous jointse; within the containment area appears to b one which strikesdips steeply to the north, and is by smoothcoated joint surfaces.Unconsolidated overburden in the area ranges to amaximum of 16* in thickness, and is characterized by adeposit of sand-silt-cobble till locally overlain by a blanket offine sand. Glacial-marine clay lies between the till andwash to the east of the containment. covered by sand,the upper surface of the till is beveled to a gently undulating,planar erosion surface upon which rest isolated boulders rangingtoin diameter.No evidence of Recent fault displacement was observed on thesurface in the Unit 2 trenches. The sub-planarcontact horizon, which occurs in three of the four trenches, shows noevidence in these areas of static or dynamic deformation.1. Purpose of Investigations Bedrock at the site of the proposed Unit containment is largelyobscured by glacial till, glacial-marine clay andsand. Bor-ingdrilled in December 1972 to a depth of 159.2* on the verticalcenterline of Unit 2, encountered thinof structural weakness inthe diorite bedrock at intervals between elevations -75* and These zones are characterized bychlorite-richhigh-angleandclosely jointed zones in chlorite-richof the bedrock. High-angle joints indip fromtoand most commonly dipTrenching investigations over the Unit 2 site werein1974 for precautionaryto ascertain theof thedeposits in the urea and to examine the natureof jointing in the underlying bedrock surface.2.Investigations Subsequent to BoringDuring April 1974, Eoringwas drilled to a depth of 97.8*at a iocatior, 33*(True) of the centerline of2 (see Appen-dix I for boring log) . This boring encounteredwith minorchlorite coatings a variouswith a zone of smoothcoated joints-64 to -79* elevations. These joints diptoand frequently show pyrite crystal growths over the chloritesurfaces.During 1974, four inclined borings,and 18, were down around the periphery of the Unit 2containment site to develop information relative to engineering of thecontainment Logs and orientation data for these boringsare presented in a July 31, 1974 report prepared byEngineers, Inc., Winchester, Massachusetts (see II) .Boringsandalong the west and south edges ofthe containment, respectively, encountered very few chlorite-coatedjoints.polished joint atdepth inappears likely to re-present the projection to depth of a prominent chlorite-coatedangle joint which is observed on the bedrock surface to trendthrough the centerline of Unit 2. There are no anomalouslypolished joints in BoringBoringdrilled northerly across the east edge of the con-tainment site, encountered polished chlorite-coated joints intermittentlyat depths of137* and 152-156*. Some ofthese joints appear tothe prominent east-west jointwhich trends through the centerline of Unit 2. This prominent jointappears to split into a number of high-angle branches as it passeseast into the zone of influence of Boring
,and(see Figure 1) .encounteredindividual jointshavecoatings.anomalously polished orrichfound,in thedepth drilled.injoint mapping of the bed-rock surfaceBoringsanddo not indicate the presence of a through-going faultinthe area of Unit 2. These borings do appear,tothat the most prominent orchlorite-coatedjoint system in thearea trends(True) through the central part of theand dipsto the north.3. Trench ExcavationsDuring August 1974, four trenches were excavated with a back-hoe to bedrock across the 'Unit 2 site, to form anwhose legs areeach203' long and intersect at right angles at thevertical centerline of the Unit. The legs trend approximately TrueNorth,Ground surfacein the area oftrenches range fromaboutto. The elevation of the bedrock surface in the floorof the trenches rangesabout -3'Stationin the East trenchtoat Stationin the South trench. Profiles of the bedrockface along the centerlines of the trenches, as surveyed by Public ServiceCompany 'of Newpersonnel, are shown on Figuresand 3.4.Exposed in the TrenchesFigure 2 shows by half-tonethe areas of bedrock mappedby J. R. Rand in the several trenches. Although the trenches wereto bedrock, throughout, the bedrock in theelevation areastoo obscured byand mud to permit the observation of jointsor other pertinentfeatures. Although much of the bedrocksurface is rough and irregular due to glacial plucking or breaking bythe backhoe, wide areas of the bedrock are locally smooth and showglacial striations.Throughout the area exposed by the trenches the bedrock con-sists predominantly of gneissoid, sometimes quartzitic, quartz dioritewhich ranges in grain size from fine- to orientations:StrikeDipStrikeDipStrikeDipNoofof'bedrock surface or the overlyingglacialin thebreccia fab-ric,isin drill corein the Unit 2 area andthroughout thearea, can beon a smooth5'ofi nThis breccia isdips steeply, is annealedcompact,andof the glaciated bedrock surface.B. Jointingon Figure 2, jointing in the bedrock is closely spaced2 containment area,a:andat less than 3'joints (greater thandips) occur in three prominentAt the centerline of Unit 2, the most continuoustrend is This set is seen----tohavechlorite-coated surfaces. __Thejointstos e t ,thejoints arestriations whichdirections ofLow-angle joints (less thanclips) appear to be somewhat morethan high-angle joints, and occurinprominentorientations:to t'ne north.characteristic&v short__lent.StrikeStrikeStrikeand SENE andand terminate against theoccur onof p l a n a r,showstriations, with no consistent striation orientationfrom joint to joint.Fromtoin the East trench, the bedrockis subject to closely-spaced jointing, and theof the bed-rocksufficiently fractured toexcavation by t'ne backhoe.Joints in this areand smooth, and show somepolishing on conchoidal surfaces. Thin gray clay fillings occur lo-cally in discontinuous patchessome joints.showno preferredand no strike direction could be determinedfor this zone.5. Unconsolidated Glacial Deposits As shown on trench profiles on Figure 3,cobble till directly overlies the bedrock surface throughout the areaexposed by the four trenches. Tillto ground surface through-out the length of the South trench, and rises locally to ground sur-face in the North trench and in the area of the Unit 2 centerline.the till does not rise to ground surface in the trenches, theupper surface of theis a gently undulating, sub-planar erosionsurface on which a layer of medium-fine sand.At the east end of the East trench, a sequence of interbedded,layered marine clays and sands lies between the and the over-lyingsand iayer. At scattered intervals in the West, Northand East trenches, isolated boulders ranging toin diameter lieenclosed insand and rest on the upper surface of the till.Subsequent to backhoe excavation of the trenches, the contacthorizon between the till and overlyingsand was exposed andcleaned by hand throughout the length of its exposure in the West,North and East trenches. The contact was inspected and photographedby J.Rand throughout its exposed length in these trenches, andits elevation determined by transit leveling along bothof each ofthese trenches. The extent of thesand deposits in the trenchand the elevations of thecontact from place to placeare shown on Figure 2.featuresobservedthiscontact in anyof the trenches to suggest either static or dynamic deformation sub-sequent to deposition of the sand on the beveled till surface. Through-out the zone of close and slippery bedrock jointing between Stationsandin the East trench, the overlyinghorizonis sub-planar and continuous.
Glacioverlying the bedrock surfacetheSouth trcrich are limited to unsorted, non-layered sand-silt-cobbletill.locallya crude stratification, and nowhereexhibit structures suggestive of podeformation.6.Examination of the overburden, bedrock surface and bedrockjoints in the Unit 2 trench excavations has revealed several distinc-tive featuresare indicative of the tectonic stability of the bed-rock at the site:A.Intermittentratified horizons in the glacial tillare not displaced over joints in the underlying bedrock.B.The undulating, sub-planar erosion surface at the top ofthe till is through-going and not subject to structural offsets or otherdeformations suggestive of faulting,C.Local exposures of glacially-scoured bedrock surfaces aresmooth across joints in the bedrock.D.Slickenside striations on closely-spaced bedrock joints ex-hibit widely divergent orientations, with no preferred attitude ororientation.John R. RandConsulting Geologist FIGURES
,o7BOULDERS ON TILL SURFACEOUTiASH AND BEACH SANDE SAND.SIL1.C2EBLE TILLLT: BENCIC IN TRENCH FLOCRSURVEYED ELEV. -.3,ASE CF SANTOP OF TREHCHBATE oF TAENT8 SL),**'\letak*,5e:frock ccpbisis prederninactlyof pissoid Newburgort Vetdiorite, fine- to mediurr.graine(locally ccarse hornblende \diorite, No diabase dikes WMnoted in the trench floor.PAC URVICE COUNAY Cr KW HAIPPIli&AIWA 51A10GEOLOGIC MAP UNIT 2 TRENCHESI Ow CoduiMIMI 10 UPDATED FSARAPPENDIX 2MGEOTECHNICAL REPORTPRELIMINARY REPORT. COMPRESSION TESTS ON STRUCTURAL BACKFILL AND SAND CEMENT,STATIONThe information contained in this appendix was not revised, but has beenextracted from the originaland is provided for historical information.
PRELIMINARY REPORT'COMPRESSION TESTS ONSTRUCTURAL BACKFILL AND SAND-CEMENTSTATIONJanuary 24, 1978Prepared forPUBLIC SERVICE CO. OF NEW HAMPSHIREandUNITED ENGINEERS AND CONSTRUCTORS, INC.Geotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890Project 77386 1.INTRODUCTION1.1 Purpose1.2 Scope1.3 ScheduleTABLE OF CONTENTSLIST OF TABLESLIST OF FIGURES2.DESCRIPTION OF STRUCTURAL BACKFILL ANDRESULTS OF INDEX TESTS2.1 Description2.2 Grain-Size Distribution Tests2.2.1 Procedure2.2.2 Results2.3 Specific Gravity Test2.3.1 Procedure.2.3.2 Results3.MOISTURE-DENSITY RELATION TEST4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTS4.1 Procedure4.2 Stress-Strain Curves For S Tests4.3 Moduli and Poisson's Ratios For S Tests5.1 Procedure5.2 Stress-Strain Curves ForTests5.3 Moduli and Poisson's Ratio ForTests6.TESTS ON SAND-CEMENT7.COEFFICIENT OFREACTION7.1 Structural BackfillNOTATIONSTABLESFIGURESAPPENDIX ASTRESS-STRAIN CURVES FOR DRAINED TESTSAPPENDIX BSTRESS-STRAIN CURVES FOR UNDRAINED TESTSPage No.243.1 Procedure3.2 Results5. CONSOLIDATED-UNDRAINED,TRIAXIAL TESTS910101344 LIST OF TABLESTable 1Schedule of Tests on Sand-CementTable 2Consolidated-DrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 3Consolidated-UndrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 4Unconfined Tests on 2-in. Cube Samplesof Sand-Cement, 5% Cement .TableCompression Tests on 2.8-in.-diameterSamples of Sand-Cement, 5% Cement.*To be added when tests are complete. 2. DESCRIPTION OF STRUCTURAL BACKFILLAND RESULTS OF INDEX TESTS2.1 Description Beard Pit No. 5 soil is a yellowish-browngravelly sand containing about two percent fines.2.2 Grain-Size Distribution Tests Two sieve analyses were performed.The grain-size dis-tribution of Beard Pit No. 5 soil as received was first, determined. The entire sample wassieved on aNO. 4 (4.75 mm) mesh and a grain-size distribution of soilpassing the No. 4 mesh was determined.The minus No. 4 mat-erial was used for triaxial testing.2.2.1 ProcedureTo determine the grain-size distribution ofthe original soil, a representative samplewas selected, weighed and air-dried.Thesample was sieved on a mesh and ag-gregates retained were removed, weighed andseparately sieved. A representative sampleof aggregates passing the mesh wasweighed, oven-dried and washed on a No. 200mm) sieve.The soil retained on theNo. 200 sieve was oven-dried, weighed andmechanically sieved.The entire quantity of soil was then sievedon a No. 4 (4.75 mm) mesh and aggregates re-tained were removed. A representative sampleof soil passing the No. 4 mesh was oven-driedand washed on a No. 200mm) sieve.Soilretained on the No. 200 sieve was subsequentlyoven-dried, weighed and mechanically sieved todetermine the grain-size distribution of thesoil to be used for compaction and triaxialtesting.2.2.2 ResultsThe grain-size distribution curve of BeardPit No. 5 soil is presented in Fig. 1.The grain-size distribution curve of the soilpassing the No. 4 (4.75 mm) sieve is presentedin Fig. 2. 4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTSSix S tests were performed on compacted specimens ofBeard Pit No. 5 soil.Only soil passing a No. 4 sieve wasused.Specimens were compacted to 90% and 95% of the maxi-mum dry unit weight as determined by ASTM Designation D1557,Method A (Section 3).Tests were performed at effectiveconsolidation pressures of 0.5, 2.0 and 6.0 ksc (7.1, 28.4,85.3 psi).Test specimens typically had a diameter ofand a height of 6.6-in.4.1 ProcedureA predetermined quantity of air-dried soil was thoroughlymixed with distilled water to a water content of 14%.Themixture was divided in seven portions of equal weight andplaced in covered containers.The compaction was performed in seven layers within asplit mold. The mold was lined with a rubber membrane whichwas held tightly to the inside of the mold by a small vacuum.The first soil layer was placed in the mold and leveled off.A l-psi surcharge was lowered onto the soil and vibratedvertically using an Ingersoll-Rand pneumatic hammer.Thehammer provided low frequency-high amplitude vibrations.Thelayer was compacted to a predetermined height to achieve thedesired unit weight.The surcharge was removed and the soilsurface scarified. Subsequent layers were added and compactedin the same manner to form a test specimen of the desired sizeand unit weight.The mold and specimen assembly was then mounted on thebottom platen of a triaxial cell. A vacuum of approximatelyof Hg was applied to the specimen to provide support tothe specimen. The mold was removed and the diameter and heightof the specimen were measured. A second membrane was placedaround the specimen and O-rings attached to seal the membranesto the top and bottom platens.The triaxial cell was subsequently assembled and floodedwith water. A chamber pressure of 0.5 ksc was applied and thevacuum released to distilled water at atmospheric pressure.When the vacuum had dissipated, distilled water was permeatedthrough the specimen to improve saturation by displacing airvoids. A back pressure of approximately 10 ksc was utilized tocomplete saturation.B-values of 0.90 or higher were measured.
..a.normalized shear stress on theplane,vs. axial strain, andThe specimen was then consolidated to the desired effectiveconsolidation pressure. Volume changes during consolidationwere measured by monitoring the flow of pore water throughthe drainage system.The test specimen was subsequently loaded axially at aconstant rate of strain of approximatelyDuringshear the specimen was allowed to drain through both ends.Volume changes were measured by monitoring the flow of porewater. Axial loads were measured with a proving ring anddeformations were monitored with an axial dial.The testwas terminated at 20% axial strain.The specimen was thenremoved and oven-dried to determine the weight of solids.4.2 Stress-Strain Curves For S Tests Results of the consolidated-drained triaxial, S, testsare plotted in terms ofb. volumetric strain,VS. axial strain.The results of individual S tests are presented in Appen-dix A and Table 2 contains the details of each S test performed.A summary of S tests performed on specimens initially com-pacted to a specific 90% compaction are plotted in Fig. 4, and95% compaction in Fig. 5.4.3and Poisson's Ratios For S TestsFigs. 6 and 7 are plots of secant modulus and Poisson'sratio, respectively, as a function of axial strain from thetriaxial S tests.Fig. 8 (top) is a plot of the initial tangent modulus andthe secant modulus at 50 of the compressive strength versusthe effective consolidation pressure,At the bottom inFig. 8 is a similar plot for the values of Poisson's ratios. 6. TESTS ON SAND-CEMENTWe herewith forward results of tests on 2-in. cubespecimens of sand-cement, so that thewill be avail-able early in this preliminary form.In Fig. 13 are plotted the stress-strain curves for un-confined tests on three replicate specimens cured for 7 days,and in Fig. 14 are the stress-strain curves for unconfinedtests on three replicate specimens cured for 28 days. De-tails of these tests are given in Table 4.The sand-cement specimens were prepared using the samesand and cement that were used at thesite for testbatches.The mixtures are shown in Figs. 13'and 14.It may be seen that the strength increased rapidly withcure time. A strength increase that is logarithmic with timewould lead to the predition of an average strength of 180psi for the specimens curedmodulus would increase to 33,800 psi.Similarly, the average
- 7. COEFFICIENT OFREACTION7.1 Structural BackfillTo determine reasonable values for the coefficient ofreaction of buried pipes, the following proceduremay be used:1.Determine whether the loading condition is"drained" or "undrained." That is, will volumechanges take place during loading (drained), orwill volume changes not occur during loading(undrained) .2.Establish the allowable diametral strain ofthe pipe. That is, select a diameter-strainthat the pipe can withstand with an adequatefactor of safety. That strain may be as lowas 0.1% for stiff, brittle pipes,to 3% or 4%for flexible pipes.3.Compute the vertical effective stress in theground at the level of the middle (springline)of the pipe.4.Choose whether the expected degree of compactionof the structural backfill is 90% Modified or95% Modified.5.Given the above data, enter the appropriatetable below, and interpolate to obtain a valueofi.e., the coefficient oftimes the pipe diameter (in psi).6.Divideby the pipe diameter to obtain thevalue ofin pci (pounds/cubic inch).
TABLE 2CONSOLIDATED-DRAINEDTRIAKIAL TESTSSTRUCTURAL BACKFILLBEARD PIT 5 SANDSTATIONPercent Compaction, PEffectiveBAt Max. Compressive StressModuli ASTM D1557, AConsoli-ValueDeviator AxialVolumeInitial At 50%InIn Triaxial CelldationStressStrain StrainCompac-InitialAftertionConsoli-MolddationMax.Stress0Stresspcf--13.8100.7s213.8100.9s313.8101.0s413.8106.413.5106.3S613.7106.3GeotechnicalEngineersInc.Project 7738623, 1978pcfksckscpsip si100.8100.889.990.090.00.500.971.641.310.416,2604,0500.310.43101.0101.590.190.290.62.000.955.882.380.0814,22011,0900.170.23101.3102.390.290.491.46.000.9515.057.28-0.6623,75018,7700.220.23106.4106.495.095.095.00.500.952.341.310.9213,5109, 6000.330.35106.4106.894.995.095.32.000.977.960.9221,33016,1400.170.27106.4107.394.995.095.86.000.9519.354.000.3429,15024,7400.200.27Test InitialDry Unit WeightsNo.WaterInIn Triaxial CellContentInitialAfterConsoli-MolddationPoisson's RatioInitial At 50%Stress3ca STATIONSTRUCTURAL BACKFILLBEARD PIT 5 SANDEffectiveASTMA Consoli-Value Deviator AxialEffectiveInitialAt 50%InIn Triaxial CelldationMinorCompac- InitialStressPrincipaltionConsoli-StressMolddationTest InitialDry Unit WeightsPercent Compaction, P13.7101.0101.2101.290.290.490.40.500.966.869.532.635,8303,13013.5100.6100.6100.989.889.890.12.000.907.948.333.1112,7305,760ii313.8100.8101.1102.290.090.391.26.000.9911.326.69.4.4638,11018,63013.6101.0101.2102.390.290.491.36.000.9512.245.734.7724.46019,05013.8106.3106.5106.594.995.195.10.500.9519.9113.837.2311,8707,180ii513.6106.3106.3106.694.994.995.22.000.9521.8714.537.9319,7708,39013.5106.3106.4107.294.995.095.76.000.9627.8811.58io.3544,01014,220GeotechnicalEngineersInc.Project77386January 23,1978p pcf cfpcf- ksc -ksckscpsiCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSNo.WaterInIn Triaxial CellContent Compac- Initial AfterConsoli-MolddationBAt Maximum Compressive UnitWeightWetUnconfinedStrengthpsiStrainModulusAtofPeakElasticity*psiCureTimedaysTestNo.TABLE 4UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5% CEMENTSTATION77-1124.066.70.8010,600123.972.50.9210,110126.285.30.8313,650Avg 74.82828-1127.4141.60.67126.2133.80.77126.8130.00.87Avg 135.0Avg 11,45033,33019,13022,760Avg 25,0709090-290-3*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386.January 23, 1978 FIGURES Lab. 4-3 rev. 0U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER50050IOI0.5GRAIN SIZE MILLIMETERSCOBBLESSANDCOARSEFINECOARSEMEDIUMIFINEIIGRAIN-SIZEDISTRIBUTIONTriaxialTestsBEARD PIT NO. 5SOILStructuralBackfillProject77386Jan.23,1978Fig.1New HampshirePublic Service Company ofEngineers Inc.Winchester,Massachusetts Lab. 4 - 3 rev. 028 May 74500100505I0.50.10.05GRAIN SIZE MILLIMETERSISILT OR CL AYCOARSEFINECOARSEMEDIUMIProject 77306Jan. 23, 1978Fig. 2II\-10go-20I-IIIIIIIIIIIIIIIIIJ - 7 0809020IO0IIIIIU.S. STANDARO SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER64 3I1420 30 40 50 70200II*IIIIIIIIIIIIIII\IIIIIIITriaxial TestsStructuralBackfillGRAIN-SIZE DISTRIBUTIONBEARD PIT NO. 5 SANDNO. 4 MATERIALPublic Service Company ofNew HampshireGeotechnical Engineers Inc. .Winchester, Massachusetts WATER CONTENT,As mixed before compaction0 After compaction1051 1 31 1 11 0 91 0 704122 024TESTSSTRUCTURAL BACKFILLMOISTUREDENSITYRELATION TESTBEARD PIT No.5 SOILJanuary1978 Fig. 3PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386ENGINEERS INC.WINCHESTER,MASSACHUSETTS PROJECT 77366DECEMBER, 1977 FIG. 43024681416182006.0AXIAL STRAIN, %ENGINEERS INC.VI NCH ESTER, M ASSACHUS ETTS 2.51.5.1.0TESTs40.5s52.0S66.006420-2024681416 1820AXIAL STRAIN,%TRIAXIAL TESTSSERVICE COMPANYOF NEW HAM SSV IR^EUC T U R A L B A C K F I L LDECEMBER, 1977 FIG. 5PROJECT 77386ISUMMARY OFDRAINED TRIAXIAL TESTSCOMPACTIONENGINEERS INC AXIAL STRAIN,F O RW0III30,0002 5,00020,00090% Modified Compaction10,000.IIIII00.40.60.81.01.21.42.0IIIW000.40.60.81.21.41.61.82.0IIIII95Compact ionIPUBLIC SERVICE gCOMPANYOF NEW TARPUSHfI2RET U R ENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386JANUARYTESTSA LB A C K F I L LDRAINED LOADING 1.61.82.000.20.40.60.81.01.21.4AXIAL STRAIN,TESTS90% Modified Compaction7.1psi0.20.40.60.81.01.21.41.62.0III95% Modified Compactionpsi .PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386JANUARYFig. 7,ENGINEERS INC.MASSACHUSETTS1.21 .o0.80.60.40.201.2.o0.80.60.40.20STRUCTURAL BACKFILLPOISSONS RATIOSFOR DRAINED LOADING 10020300E moduluscompactionEmodulus50%peakcompactionE modulus95% compactionE modulus atpeokcompaction95% compactionvat 50%peak95%90% compactionat 5 00.50.40.30.20.10kg(Multiply by 14.22 for psi)SERVICE COMPANYqF NEI HAMPSHIRECENGINEERS INC.YINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSUMMARY OFFSTRUCTURALILLDRAINEDTESTSPROJECT 77386FIG. 8 4678910TEST NO.0.502.0002468141618206.006.00AXIAL STRAIN , %SERVICE COMPANYSUMMARY OFTRIAXIAL TESTSOF NEW H'WWHIJRCET UR A LB A C K F I L LUNDRAINED TRIAXIAL TESTS90% COMPACTIONENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. 9 TEST NO.*3c kg/cm2kg/cm2R40.50R52.00R66.0006421214R6STRESS-STRAINR63024681012141618 20AXIAL STRAIN,%PUBLIC SERVICE COMPANYOF NEW HAMPSHIREGEOTECHNICAL ENGINEERS INC.WINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSTRUCTURAL BACK FILLPROJECT 77386SUMMARY OF CONSOLIDATED-UNDRAINED TRIAXIAL TESTS95% COMPACTIONDECEMBER,1977 FIG. 10 SECANT MODULUS,psiundrained loadingSECANT MODULUS, Es, , psiundrained loading0DXriI I.II ENGINEERS INC.*WINCHESTER, MASSACHUSETTSPROJECT 77386DECEM 8FIG.(Multiply by 14.22 for psi)00 90% Compact ion90% CompactionCompaction 95% CompactionNOTE POISSONS RATIO FOR UNDRAINEDTESTS MAY BE TAKEN AS 0.49 TO 0.50
,12080400I2345AXIAL STRAINSand-Cement Mixture (by weight):1 part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimens7 daysUnit weight after cure7-1 124.07-2 123.97-3 126.2Strain control. loading at 1.5 mm/minPublicCompanyof New HampshireEngineers Inc.Winchester,MassachusettsCOMPRESSION TESTS7-DAY CURE5% CEMENTJanuary 1978Fig. 13Triaxial TestsStationSand-CementBackfillProject 77386
.,AXIAL STRAINSand-Cement Mixture (by weight):1part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimensCured 28 daysUnit weight after cure28-1 127.428-2 126.228-3 126.8Strain control loading at 1.5Public Service Companyof New HampshireTriaxial TestsCOMPRESSION TESTSSand-CementBackfill28-DAY CURBStation5% CEMENTGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386January 1978Fig. 14..
APPENDIX A SERVICE COMPANYPROJECT 77386ENGINEERS INC.10121618201.0VOLUMESTRESS STRAINAXIAL STRAIN,%TEST90% CompactionTRIAXIAL TESTSITRAL BACK F I L LCONSOLIDATED-DRAINEDTRIAXIAL TESTDECEMBER, 1977 FIG.OF NEW HAMVTHIRITC T 2.50.5STRESS STRAIN002468101214161820AXIAL STRAIN,%TEST S290% Compaction= 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF ^EW RHAUMPCS4IR15 R A LB A C K F I L LGEOTECHNICAL ENGINEERS INC.PROJECT 77386DECEMBER, 1977 FIG. A21.50-0.5VOLUME STRAINCONSOLIDATED-DRAINEDTRIAXIAL TEST S2 2.5STRESS-1.5,VOLUME-2.0.02468101214161820AL STRAIN,%TEST S3 90Compaction3c = 6.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386DECEMBER, 1977 2.51.51.00.5064202VOLUME STRAIN681012141618AXIAL STRAIN,%TEST S495% Compaction3c = 0.5T R I A X I A L^aSERVICE COMPANYICONSOLIDATED-DRAINEDOF NEW HAMPSHIRESTRUCTURAL BACKFILLPROJECT 77386GEOTECHNICAL ENGINEERS INC .YINCHESTER,MASSACHUSETTSDECEMBER, 1977 1.5.1.00.5 . .STRESS0VOLUME STRAIN2461012141620AXIAL STRAIN,%TEST95% Compaction2.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETEST,STRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386 DECEMBER, 6PROJECT 77386I DECEMBER, 1977 FIG. A2.5STRESS STRAIN-1.024681012741618 20VOLUME STRAINAXIAL STRAIN,%TEST S695% Compaction= 6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,SEOTECHNICAL ENGINEERS INC.1TRIAXIAL TESTSSTR UCTURAL BACKLL 4.03.02.0I>3=1.64E6260 psi4050 psi.1.00.60.40.200.40.81.21.6AXIAL STRAIN,%TEST90% Compaction= 0.5CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPROJECT 77386DECEMBER,1977 FIG. A7ENGINEERS INC.MASSACHUSETTSSERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILL 8.0= 5.883E014220 psi11090 psi6.04.0I2.00-0.1-0.2-0.3-0.400.81.21.62.0AXIAL STRAIN,%TEST S290% Compaction= 2.0SERVICE COMPANYOF NEW HAMPSHIRET R I A X I A L TESTSSTRUCTURAL BACKFILLENGINEERS INC.VVINCHESTER, MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S2Expanded ScalesPROJECT 77386DECEMBER,!977 FIG.
AXIAL STRAINTEST S390% Compaction6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,STRUCTURAL BACKFILLPROJECT 77386TESTSTEST S3Expanded ScalesENGINEERS INC.WINCHESTER, MASSACHUSETTS 3= 2.34E013510 psiE9600 psi= 0.3350= 0.3500.40.81.2162.0AXIAL STRAINTEST S495% Compaction= 0.5SERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILLENGINEERS INC.MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S4Expanded ScalesPROJECT 77386IFIG.
TEST95% Compaction3c = 2.0TESTSSKTRUCFTURALILLPROJECT 77386CONSOLIDATED-DRAINEDTRIAXIAL TEST S5Expanded ScalesF I G .SERVICE COMPANYOF NEW HBAMPSAHIRECMASSACHUSETTSENGINEERS INC.-0.20.40.2AXIAL STRAIN,%32133016140=7.96kg/cm-psipsi8.062.I4.
I-0.1-0.3,1 6 . 012.04.08.0 .AXIAL STRAINTEST95% Compaction= 6.0PROJECT 77386DECEMBER,1977 FIG.CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.NINCHESTER, MASSACHUSETTSTESTSSTRUCTURAL BACKFILL APPENDIX 246814161820AXIAL STRAIN , %-SSPA81012141618TEST90%Compactiona3c1412108606PUBLIC SERVICE COMPANYOF NEW HAMPSHIRESTRUCTURALTRIAXIALPROJECTTESTSBACKFILL77386IDECEMBER,1977CONSOLIDATED-UNDRAINEDTRIAXIAL TEST 3.53.02.51.5STRESS PA0.5TEST90% Compactiona 3c002468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSOFSHf %P ^ H^R f U RTRIAXIAL TESTA LB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. B2 1.25"1.0DO.750.25STRESS-S TRAINSPA01.00.500.751.001.251.501.752.002.252.TEST90% Compaction6.0.. 2524681214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYOF NEW HOMPSMIRE CPROJECT 77386DECEMBER, 1977 FIG.T R I A X I A L TESTSSTKRUCTFURALILLCONSOLIDATED-UIJDRAINEDTRIAXIAL TESTENGINEERS INC.WINCHESTER, MASSACHUSETTS STRESS PASTRESS0.250.500.751.001.251.501.752.002.25TESTCompaction3c6.002468101214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIALTESTSOF NEW HAMPSHIRETRIAXIAL TESTBACKFILLSTRUCTURAL,ENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG. B4PROJECT 77386 s TRESS PASTRESS-S05101520253035404550TEST90% Compactiona 3c0024681012 14 1618 20AXIAL STRAIN, %PUBLIC SERVICE COMPANYTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDO F N E ^l 0 ALY PCS1^I RUE R ATRIAXIAL TESTLB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER, 1977 FIG. B5 S ESS PA-S10121416TEST90% Compactiona 3c= 2.02468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYTRIAXIAL TESTSOS TF RNEU CHATP UHIRREA LTRIAXIAL TESTB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG.PROJECT 77386 0.502468lo14161820AXIAL STRAIN ,ENGINEERS INC..WINCHESTER,MASSACHUSETTS00.51.01.52.02.53.03.54.04.55.PROJECT 77386TEST90% Compaction6.0DECEMBER, 1977 FIG. BSTRESS PA TRIAXIAL TESTSSTRUCTURAL BACKFILLPROJECT 773860.40 . 81.21.6AXIAL STRAIN,4.01.03 . 020TEST90% Compaction= 0.53cCONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.WINCHESTER, MASSACHUSETTS 4.03.0bI20.1.0AXIAL STRAIN, %TEST90% Compactiona 3c = 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESENGINEERS INC.WINCHESTER, MASSACHUSETTS1PROJECT 77386DECEMBER,1977 CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER,19778.00.40.81.2AXIAL STRAIN,.%TEST90% Compaction ,6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREE N G I NWINCHESTER, MASSACHUSETTST R I A X I A L TESTSSTRUCTURAL BACKFILLE E R SI N C;PROJECT 77386 AXIAL STRAIN,ENGINEERS INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG00.40.81.21.68.0TEST90% Compaction= 6.0.6.03c PUBLIC SERVICE COMPANYOF NEW HAMPSHIRECONSOLIDATED-UNDRAINEDT R I A X I A L TESTSTRTAXTALISTRUCTURAL BACKFILLSCALESTEGEOTECHNICALCHNICA L ENGIENGINERSNEER SINC.INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977AXIAL STRAIN,8.02.0TEST90% Compaction.3c= 0.5 00.40.81.21.62.0AXIAL STRAIN,20164I12TEST90% Compaction3 c = 2.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERSWINCHESTER, MASSACHUSETTSTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESPROJECT 77386IDECEMBER, 1977 AXIAL STRAIN,20.016.04.012.08.000.81.21.62.0TEST90% Compaction= 6.0 kg/cm.CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER, 19773c ENGINEERS INC.1017 MAIN STREETWINCHESTERMASSACHUSETTS 01890729-1625February 14, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th FloorManchester, NH 03105
Subject:
Interim Test Results on Sand-Cement BackfillStation
Reference:
Preliminary Report, Compression Tests onStructural Backfill and Sand-CementStation,January 24, 1978
Dear Mr.The purpose of this letter is to present data on moduli deter-mined on sand-cement backfill at the request of United Engineersand Constructors Inc. The data herein supplements the data in thereference and will be incorporated in the completed version of thatreport.Themodulus values were submitted to Mr. Pate1ofby telephone on February 13,
1978.The stress strain curves for three unconfined compression testson cylindrical specimens are shown in the enclosed Fig. 15 and thetest data are summarized in the enclosed Table 5.The following values of the coefficient ofreactionwere computed for the cube and cylindrical specimens cured for 28days..
Mr. JohnFebruary 14, 1978FOR SAND-CEMENT BACKFILL28-DAY CURETabulated values are in psiEffectiveVerticalStress atAllowable Diameter Strain, Springline0.020.10.30.5CUBE SPECIMENS100,000CYLINDRICALSPECIMENS200,00089,00060,00036,000The stress strain curves for the cylindrical specimens show aninitial straight line portion withhigh modulus of elasticity.At axial strains of about 0.03% there is a break in the curves and asecond straight line is followed up to near the peak strength.Thetangent modulus of this second straight line portion of the curves isabout one-third of the initial modulus.Fig. 16 shows the variation ofthe secant modulus with axial strain for the unconfined tests on cylin-drical specimens.Seating problems occurred in the tests on the cube specimens, asseen in Figs. 13 and 14 of the above reference, and thus the high initialmodulus observed for the cylindrical samples was not observed for thecubes. However, the second straight line slope for the cylindricalspecimens in Fig. 15 is in good agreement with the straight line portionof the curves for the cube specimens.The compressive strength of thecube specimens is somewhat higher than that of the cylindrical specimens,probably as a result of the more significant end restraint of the cubespecimens.For these two reasons we feel that the results of tests oncubes and cylinders are consistent with each other, but that the resultsfor tests on cylinders are more reliable and should be used to establishmoduli ofreaction.
Mr. JohnFebruary 14, 1978We have also provided by telephone various friction coefficientsand estimates of shear wave velocities in the compacted soil. Thesedata will be confirmed in writing at a later date.Sincerely yours,Steve J. PoulosPrincipalEncl.cc:R.YAEC w/l encl.D.w/l encl.A. Desai,w/l encl.
ConfiningCompressiveStrainInitialStressStrengthAtModulus ofPeakElasticitykscpsi%psiCureTestUnitTimeNo.WeightWetdaysTABLE 5 COMPRESSION TESTS ON 2.8-IN.-DIAMETER.SAND-CEMENT SPECIMENS, 5% CEMENTSTATION2828-O-l126.20.002828-O-2124.80.002828-O-3124.10.0091.00.6588.8.0.58106.10.8075,00052,20034,30095.3Avg 50,500Geotechnical Engineers Inc.Project 77386February 7, 1978 StationTriaxial TestsProject 77386February 1978Fig. 15Engineers Inc.Winchester, MassachusettsPublic Service Company ofSand-CementBackfillSpecimens Tested:specimens28-day cureUnconfined testsStrain control loading at1.10.81.6AXIAL STRAIN ,Sand-Cement Mixture:Xa1part cement16.18 parts sand (oven-dry)2.79 parts waterCOMPRESSION TESTS2.8-IN.-DIAMETER SPECIMEN5% CEMENT, 28-DAY CURE Winchester, MassachusettsProject 77386600 .00.20.40.81.01.2STRAIN AT PEAKAVERAGE= ksAXIAL STRAIN,,Triaxial TestsSand-CementBackfillStationPublic Service Company ofNew HampshireGeotechnical Engineers Inc.February 197816SECANT MODULUS VS STRAINSPECIMENS5% CEMENT,CURE 203060500AXIAL STRAIN,, %0.20.4=
ENGINEERS INC.1017 MAIN STREET. WINCHESTERMASSACHUSETTS 01890Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street-11th floor..Manchester, NH 03105
Subject:
Interim Test Results on Sand-Cement'BackfillStation
Reference:
Preliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978Bear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letter of February 14.These triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 33 days instead ofthe intended 28 days because of the February 6, 1978 blizzard herein Boston. The test data are summarized in a revised Table 5 andthe stress strain curves are presented in Fig. 17.The modulus and strength data were estimated for 28-day curingon the basis of the rate of change of modulus and strength withtime as measured using the cube specimens (see referenced report).The estimated values of strength and modulus for 28-day cure alsoare shown in Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letter of February14. The following table lists all values obtained to date for thesand-cement specimens.
FOR SAND-CEMENT BACKFILLCURE, 5% CEMENTGEOTECHNICALINC.cc:R. Pizzuti, YAEC w/l encl.w/l encl.A. Desai,w/l encl.D.. Patel,w/l encl.Mr. JohnFebruary 27, 1978Tabulated values are in psiEffectiveAllowable Diameter Strain, %VerticalStressatSpringlinepsi0.10.30.5.CUBESPECIMENS0100,000.CYLINDRICALSPECIMENS0200,00089,00060,00036,00042.7138,000163,000129,600Sincerely yours,Steve J. PoulosPrincipalGC:msEncl.
TABLE 5COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%STATION372.3652.1035,00033,6003762.4033,30036931,7003641.4040,00035738,40042.742.7124.8332833283328EstimatedTestNo.days28-O-lUnitWeightWetConfiningCompressiveStrengthpsiStrainInitialatModulus ofPeakElasticitypsi126.20.00910.6575,0002828-O-2124.80.00890.5852,200.2828-O-3124.10.001060.8034,300NOTE: 1) The percentage of cement is computed as the ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.2) The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.Geotechnical Engineers Inc.Project 77386February 7, 1978Revised February 24, 1978 3= 42.7 psi0.8 IIII 0051.0I.52.02.53.03.54 . 0AXIAL STRAIN, %Project 77386Feb. 23, 1978Fig.17StructuralBackfillTriaxial Tests2.8-IN.-DIA., 5% CEMENT33-DAY CURE,=SAND-CEMENT SPECIMENSPublic Service Company ofNew HampshireEngineersWinchester,Massachusetts 1017 MAIN STREET. WINCHESTER. MASSACHUSETTS 01890729-1625March 10, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire.1000 Elm Street11th FloorManchester, NH 03105Interim Test Results on Sand-Cement Backf illStationPreliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978
Dear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letters of February 14 and27.Three triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 28 days and weretested under a confining stress of 7.1 psi.The test data aresummarized in a revised Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letters of February14 and 27. The following table lists all values obtained to datefor the sand-cement specimens:
Mr. JohnMarch 10, 1978FOR SAND-CEMENT BACKFILL28-DAY CURE, 5% CEMENTTabulated values are in psiEffectiveVerticalAllowable Diameter Strain, Stress atSpringlinepsi0.10.30.5CUBE SPECIMENS01 0 0, 0 0 0CYLINDRICAL SPECIMENS0200,00089,00060,0007.1115,000106,00079,60042.7138,000163,000129,600*Modulus value determined at strains greater than the strain at peakcompressivestrength.Geotechnical Engineers Inc.Project 77386Revised March 6, 1978 Mr. JohnMarch 10, 1978,GEOTECHNICALINC.GC/SJP:msEncl.cc: R. Pizzuti, YAECD.A. Desai,D. Patel,Three unconfined tests were performed on cube specimens ofsand-cement cured for 90 days. The test data are summarized ina revised Table 4.The stress-strain curves for the additional tests will betransmitted as soon as they have been drafted.Sincerely yours,Steve J. PoulosPrincipal UnitWeightWetCureTimedaysTestNo.TABLE 4 UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5 % CEMENTSTATIONUnconfinedStrengthpsiStrainModulusAto fPeakElasticity*%psi28907-l124.07-2123.97-3126.228-l127.428-2126.228-3126.890-l124.490-2124.590-30.8010,6000.9210,1100.8313,650Avg 11,450141.60.67.33,3300.7719,1300.8722,760 Avg 135.00.951.080.84Avg 28,200Avg 25,07026,32027,03031,250*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386January 23, 1978Revised6, 1978 126.2124.8124.175,00052,20034,3002828-O-l2828-O-22828-O-30.0910.650.0890.580.0.1060.80TABLE 5--COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%CureTimeNo.daysUnitWeightWetConfiningCompressiveStrengthpsiStrain.InitialatModulus ofPeakElasticitypsi283333283342.742.7423722.1035,00028282 8281)372.3762.4033,3001.4040,00039,6007.11197.1134124.3The percentage ofthe ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.34,60037632,9003643640.6032,6000.9022,9000.9717,400Geotechnical Engineers Inc.Project 77386February1978Revised-February 24, 1978Revised March 6, 1978 UPDATED FSARAPPENDIX 2NGEOTECHNICAL REPORT TEST FILL STUDY OF QUARTZITE MOLE CUTTINGS The information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
William R.Senior EngineerStevePrincipalTEST FILL STUDYOFQUARTZITE MOLECUTTINGSSubmitted toPublic Service Company of New HampshireSubmitted byGeotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890July 13, 1979Project 76301 81010101111111314TABLE OF CONTENTSPage No.LIST OF TABLESLIST OF FIGURES1.INTRODUCTION1.1 Purpose1.2 Background1.3 Summary2.CONSTRUCTION OF TEST FILLS2.1 Gravelly Sand2.2 Molecuttings (Controlled Placement)2.3 Molecuttings (No Special Controls)2.4 Stratified Molecuttings and Gravelly Sand3.PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand3.2 Molecuttings (Controlled Placement)3.3 Molecuttings (No Special Controls)3.4 Stratified Molecuttings and Gravelly Sand4.PLATE LOAD TESTS5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS5.1 Grain-Size Limits5.2 Lift Thickness5.3 Determination of In-Place Dry.Density5.3.1 Gravelly Sand5.3.2Molecuttings5.4 Determination of Percent Compaction5.5 Water Content ControlTABLESFIGURESAPPENDIX ARECOMMENDEDFOR PLACEMENTAND FIELD CONTROL OF MOLECUTTINGSAPPENDIX BPLATE LOAD TESTS LIST OF TABLESTable 1Summary of Field Density TestsGravelly Sand Test FillTable 2Summary of Field Density TestsMolecuttings (Controlled Placement) Test FillTable 3Summary of Field Density TestsMolecuttings (No Special Controls) Test FillTable 4Summary of Field Density TestsStratified Molecuttings and Gravelly Sand Test FillTable 5Summary of Plate Load Tests Results LIST OF FIGURESFig. 1Plan View of Test FillsFig. 2Profile of Test FillsFig. 3Profile of Test FillsFig. 4Compaction CurvesGravelly SandFig. 5Grain Size CurvesGravelly Sand Test FillFig. 6Compaction CurvesMolecuttings.Fig. 7Grain Size CurvesSamples of MolecuttingsFig. 8Modulus of Elasticity vs Percent CompactionMolecuttings.Fig. 9Water Content Sand ConeNuclear Density MeterGravelly SandFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryGravelly SandFig.Water Content Sand Cone vs Nuclear Density MeterDet., MolecuttingsFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryMolecuttings the same percent compaction.problem was addressed byInvestigation of the resistivityINTRODUCTION1.1 Purpose The intake and discharge tunnels atStation arebeing excavated using a tunnel boring machine, more commonlytermed a mole. The excavated material from the mole is awidely-graded crushed stone commonly termed tunnel muck, which,for this report, shall be termed "molecuttings."The purpose of the test fill study was to determine if thequartzite molecuttings obtained from-the tunnel excavationscould be used for Safety and Nonsafety-Related Structural Fill.Construction of the test fills provided the opportunity to ob-serve the behavior of the molecuttings during placement andobtain data necessary to develop procedures to control the com-paction of the molecuttings during placement.1.2 Background The molecuttings from the quartzite bedrock in the tunnelsare widely-graded crushed stone containing up to 13% passingthe No. 200 sieve.The grain size curve of the molecuttingsplots below the lower limit of the Safety and Nonsafety-RelatedStructural Backfill specification.The resistivity of thecuttings is generally below the specified minimum value of10,000Thus, although the molecuttings appearedsuperior to the gravelly sand structural fill as a backfillmaterial, it was rejected because the gradation and resistivityrequirements did not comply with the specifications.Useofthe molecuttings for Safety and Nonsafety-Related StructuralFill required that selected tests be performed which would demon-strate that the molecuttings were as good or better than thepresently used gravelly sand when both materials were placed atThe Safety and Nonsafety-Related Structural Fill is usedfor backfill around pipes and conduits, under floor slabs, roads,etc.For these applications the deformation characteristics ofthe backfill will control the soil support of the pipes andsettlements of structures. One method of determining the defor-mation properties of a soil is by determining the soil modulusby the use of a plate load test.Plate load tests were performedon carefully constructed test fills consisting of (a) gravellysand, (b) molecuttings, anda test fill of essentially alter-nating layers of gravelly sand and molecuttings which herein willbe referred to as the stratified gravelly sand and molecuttings test fill The modulus from each test fill was used as a means of comparingthe desirability of the molecuttings versus the gravelly sand foruse as Safety and Nonsafety-Related Backfill.The molecuttings are widely graded and containhigh percentages of stone retained on thesieve.In manycases the percentretained on thesieve exceeds theallowable limits for the Modified AASHO compaction testThus, it was necessary to determine by means of field and labora-tory tests performed during construction of the test fill howconstruction control of the placement of the molecuttings shouldbe handled.., 1.3 Summary The results of the plate load tests indicate that thecuttings will provide superior support for pipes and structuresthan the gravelly sand currently accepted for Safety andsafety-Related Structural Fill when both materials are placed atthe same percent compaction.The molecuttings and gravelly sandwill provide about equivalent deformation properties when thepercent compaction of the molecuttings is as much as 2 to 3%lower than the gravelly sand.Therefore, the use of molecuttingsfor Safety and Nonsafety-Related Structural Fill is recommended.Further, it is recommended that the percent compaction of themolecuttings for Safety and Nonsafety-Related Structural Fill be95% andrespectively.The molecuttings used in constructing these test fills werewidely graded crushed stone with up to 7% passing the No. 200sieve.The water content of the material varied from 3 to 4% upto 10% during placement.Because of the grain-size distributioncompaction of the molecuttings was sensitive to fluctuations inthe water content of the material. Based on data obtained fromtests performed during construction of the test fills, limitationson the grain-size distribution and water content'of thecuttings during placement have been recommended in Section 5.Construction of the test fills indicated that placement ofthe molecuttings can be controlled by modifying standard testingprocedures.The in-place dry density can be measured using thenuclear density meter and the laboratory reference dry densitydetermined by modifying the currently specified compaction tests.Details of the construction of the test fills, performanceand results of the plate load tests, and procedures for controlof placement and compaction of molecuttings are presented in thefollowing sections. 2.CONSTRUCTION OF TEST FILLSFour test fills were constructed for this study.Theorientation of the test fills is shown in Fig. 1.The soilsand details of placement for each test fill is presented below.2.1 Gravelly Sand Gravelly sand satisfying the requirements for Safety andNonsafety-Related Structural Fill Specifications 9763-8-5 and9763-8-4 was placed in 8-in. -thick loose lifts and compactedto a minimum of 95% of the maximum dry density as determined byASTM D1557, Method D.Satisfactory compaction was generallyachieved by applying water to the surface of the loose lift andcompacting with six coverages with the Mikasa double drum roller.Eight lifts of gravelly sand were placed and compacted, result-ing in a total height of about 4 ft.2.2 Molecuttings (Controlled Placement)The construction of this test fill was controlled to achievethe compaction requirements of Safety and Nonsafety-RelatedStructural Fill (i.e., 95% of the maximum dry density as deter-mined by ASTMMolecuttings were placed in 8-in. loose lifts and compactedto 95% compaction. To achieve 95% compaction, control of thewater content to within a few percent of the optimum water con-tent, and numerous coverages with the Mikasa double drum rollerwas required. Attempts at controlling the water content includedmixing of wet and dry molecuttings and adding water tocuttings with water contents 2 to 3% below optimum. Molecuttingsplaced at water contents several percent higher than optimumcould not achieve 95% compaction until sufficient drainage hadreduced the water content to near the optimum value.Eight liftsof molecuttings were placed and compacted resulting in a totalheight of about 4 ft.2.3 Molecuttinqs (No Special Controls)Construction of this test fill involved the placement of themolecuttings with limited control of water content and a specifiedcompactive effort. The molecuttings were generally placed inG-in. loose lifts and compacted by six coverages with the Mikasadouble drum roller.In some instances, water content control waslimited to permitting drainage of a compacted layer overnight be-fore placement of the succeeding layer.Eight lifts ofcuttings were placed and compacted. 2.4 Stratified Molecuttings and Gravelly Sand The first three lifts of this test fill were constructedthe same way as the test fill of Molecuttings (No Special Con-trols). The water content of the molecuttings placed for thethird lift was about 3% higher than optimum. The surface ofthe third lift was saturated and became severely rutted duringcompaction.Sandwiching layers of gravelly sand between layersof molecuttings was done to determine (1) if the gravelly sandprovided drainage of sandwiched layers of molecuttings and (2)the feasibility of constructing a backfill of stratifiedgravelly sand and molecuttings (which may be required in thezone of frost penetration).Therefore, lifts 4 and 6 were con-structed using gravelly sand.Lift 4 was compacted with sixcoverages of the Mikasa double drum roller and lift 6 was com-pacted to at least 95% compaction. Molecuttings for lifts 5, 7and 8 were generally placed in 8-in. loose lifts with limitedwater content control and compacted with six coverages of theMikasa double drum roller. 3. PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand The percent compaction of each lift was determined by per-forming in-place density tests and laboratory compaction tests.The average percent compaction of the gravelly sand test fillwas 97.4%.The in-place density for each lift, after compaction, wasdetermined by performing two 6-in. -diameter Sand Cone (SC)tests and three Nuclear Density Metertests.Theplace density determined by the NDM was generally performed atprobe depths of 4 in. and 8 in.The two SC tests were performedadjacent to two of the NDM tests to provide a comparison of thewater content and dry density measured by each 'method.The SCand NDM tests were generally performed within a 5-ft radius ofthe plate load test location. .One-point compaction samples were obtained adjacent to theSC and NDM test locations. The one-point samples were compactedin accordance with ASTM D1557, Method D.The maximum dry densityfor the one-point sample was determined by plotting the one-pointdry density on a family of curves for the gravelly sand and in-terpolating the maximum dry density.The percent compaction wascomputed by dividing the in-place dry density by the correspondingone-point compaction determined maximum dry density.Table 1presents the summary of the percent compaction achieved in thetest fill.A profile of the test fill and the average percentcompaction for each lift is shown on Fig. 2.Three compaction tests were performed in accordance withASTM D1557, Method D, on bag samples of gravelly sand obtainedfrom material placed in lifts 2, 4 and 7.The compaction curvesand related grain-size curves performed by Pittsburgh Testing Labsare shown on Figs. 4 and 5, respectively.3.2 Molecuttings (Controlled Placement)The average percent compaction achieved for this test fillwas 96.7%.The in-place density of each lift after compactionwas determined by performing several NDM tests and, when thesoil conditions were acceptable, oneSC test.The SC test was performed adjacent to a NDM test to provide acomparison of the water content and dry density measured by eachmethod. Observations in the field and data from tests indicatedthat the hole excavated for the SC test tended to squeeze in orreduce in volume when the molecuttings were placed and compacted at water contents above or near optimum.Results from the SCtests when these conditions existed gave unreasonably high drydensities, and, as a result, SC tests were considered valid onlywhen they were performed in areas where the water content of themolecuttings was less than 5%. A more complete discussion ofthis problem is presented in Section 5.The SC and NDM testswere generally performed within about a 5-ft radius of the plateload test.Generally, several NDM tests were required before a lift ofthe molecuttings was compacted to a dry density that was esti-mated to provide 95% compaction. One-point compaction sampleswere obtained adjacent to the series of NDM and SC tests that, indicated about 95% compaction had been achieved.The one-pointsamples were compacted in accordance with ASTM D1557, Method C,except the minusmaterial was included for compaction.The maximum dry density for the one-point sample was determinedby plotting the one-point dry density on a family of compactioncurves for molecuttings and interpolating the maximum dry density.Correction of the in-place dry density to account for theplusmaterial, which was removed for the laboratory test,was necessary in order to determine the percent compaction. De-tails of the correction procedure are presented in Appendix A.The percent compaction was computed by dividing the correctedin-place dry density by the corresponding maximum dry densitydetermined by the one-point compaction technique.Table 2 pre-sents the summary of the percent compaction achieved in thetest fill. A profile of the test fill and the average percentcompaction for each lift is presented in Fig. 2.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on l&-in. sieveon bag samples of molecuttings from lifts 4 and 6.The compac-tion curves and related grain-size curves are shown on Figs. 6and 7, respectively.3.3 Molecuttings (No Special Controls)The average percent compaction of this test fill was 93.0%.The water content of the molecuttings during placement was gen-erally above optimum and was not controlled during compaction.Sand Cone tests to determine the in-place dry density were notperformed because of the inaccuracy in performing the test inmolecuttings compacted at water contents near or above optimum.The in-place dry density was determined by performing at least two and most usually three to five NDM tests at probe depthsof 4 and 8 in.The NDM tests were generally performed withina 5-ft radius of the plate load test location.One-point compaction samples were obtained adjacent'to theseries of NDM tests that indicated the next lift of molecuttingscould be placed.In some cases after a lift had been compacted,NDM tests performed, and one-point samples obtained, the liftwas permitted to drain overnight and additional NDM tests takenin the morning. One-point compaction samples generally were notobtained for the NDM tests performed after drainage. The pro-cedure to compute the percent compaction for each in-place den-sity test was the same as described in the previous section.Table 3 presents the summary of the percent compactionachieved in the test fill. A profile of the test fill and theaverage percent compaction for each lift is presented in Fig. 3.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on thesieve on bag samples obtained from lifts 2A and 7A. The com-paction curves and the grain-size curve for lift 2A are shownon Figs. 6 and 7, respectively.3.4 Stratified Molecuttings and Gravelly SandThe average percent compaction of the gravelly sand andmolecuttings test fill was 92.8%.Molecuttings were used forlifts 1, 2, 3, 5, 7, and 8 for this test fill.The in-placedry density and percent compaction of the molecuttings was deter-mined in accordance with the procedure described in the previoussection. Lifts 4 and 6 of the test fill were constructed usinggravelly sand. The in-place density for lift 4 was determinedby four NDM tests. One SC test and 3 NDM tests were performedin lift 6. The maximum dry density and computation of the per-cent compaction at each in-place density test location was asdescribed in the section for gravelly sand.Table 4 presentsthe summary of the percent compaction in the test fill. A pro-file of the test fill and the average percent compaction of eachlift is presented in Fig. 3. 4.PLATE LOAD TESTSFive plate load tests were performed on the four testfills.The plate load test number, test fill and date of thetest is presented below.Plate Load Test No.Test FillDate of Test1Gravelly SandJune 7, 19792MolecuttingsJune 14, 1979(No SpecialControl) .StratifiedJune 15, 1979cuttings andGravelly SandMolecuttingsJune 18, 1979(ControlledPlacement)5Molecuttings(No SpecialControl)The locations of the tests are indicated on Fig. 1 and de-tails of the procedure are presented in Appendix B.In briefthe procedure was as follows:an-diameter steel platewas generally placed 12 in. below the surface of the test filland loaded to produce contact stresses to 4 tsf and then to 12Deflections of the plate were measured and recorded.The results of the plate load tests are presented in Figs.B2 through B6. Values of Young's Modulus, E, were calculatedfrom the results of the plate load tests using elastic theory.A description of the analysis is presented in Appendix B. Asummary of the modulus calculated for each test is presented inTable 5.The percent compaction indicated in Table 5 representsthe average percent compaction of lifts within the zone of signi-ficant stress increase due to the load on the plate.For anin. -diameter plate this zone is aboutto 36-in.-thick.The soil modulus determined by the plate load test vs per-cent compaction is plotted on Fig. 8.The results indicate thatthe molecuttingshave a much higher modulus than the gravelly sandwhen both materials are compacted to the same percent compaction.In fact, the modulus of the molecuttings compacted to 93% compac-tion is approximately equivalent to the modulus of the gravellysand placed at 97% compaction.Plate Load Test No. 5 (PLT-5) wasperformed 13 days after and about 4 ft away from Plate Load TestNo. 2 (PLT-2).The soil modulus for PLT-5 was about two timesJune 27, 1979 the modulus for PLT-2. The increase in modulus may have beencaused by densification of the molecuttings as a result ofdrainage over the 13 day period between the performance of thetwo tests. Assuming that the molecuttings were saturated afterPLT-2 and the water content reduced by 1% during a period of 13the in-place dry density would have increased by 2 to 3 pcfor about a 1 to 2% increase in the percent compaction.Themodulus for PLT-5, as a result of the densification, nearly plotson the line from PLT-2 to PLT-4.Test PLT-3 was performed on the stratified molecuttings andgravelly sand test fill. The average percent compaction of themolecuttings and gravelly sand was 92.5 andrespectively., Plate load tests, PLT-2 and PLT-1, were performed on separatetest fills of molecuttings and gravelly sands compacted to aboutthe same percent compaction and the moduli were 7,300 psi and 10,100respectively.The moduli determined for the stratified testfill, however, was 17,000 psi.Based on the results of PLT-1 andPLT-2 the anticipated modulus determined by FLT-3 was between 8and 10,000 psi.The high modulus measured by PLT-3 may have beencaused by one or more of the following factors:1.Distribution of the load may have been more rapid forthe layered fill than in a homogeneous fill, and2.Drainage of the molecuttings and related increases indry density and modulus may have accelerated faster inthe stratified test fill than in the homogeneouscuttings (No Special Controls) test fill due to drainagethrough the gravelly sand layers.
- 5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS The purpose of this section is to present recommendationsfor the placement and field control of molecuttings based onfield and laboratory data obtained during construction of thetest fills.Review of the data obtained provided the information neces-sary to make recommendations on the limits for grain size, liftthickness, determination of in-place density and percent compac-tion, and control of water contents of the molecuttings. Adiscussion of each of the items is presented below.5.1 Grain-Size LimitsGrain-size analyses were performed on thre'e samples of themolecuttings used for the test fills.The grain-size curvesare presented on Fig. 7.The molecuttings were generally widelygraded with uniformity coefficients of 45 to 100.The maximumparticle size was generally less than 3-in.-diameter and thepercent by weight passing the No. 200 sieve was from 5 to 7%.Based on these and other grain-size analyses recommendations forgradation requirements were developed and are presented inAppendix A.5.2 Lift ThicknessThe molecuttings were placed in 8-in.-thick loose liftsduring construction of the test fills. Observations made duringplacement of the molecuttings indicated that the ability toachieve a specific percent compaction was mostly affected by thewater content of the material rather than the thickness of thelift. When the molecuttings were placed at water contents aboveoptimum, a specific degree of compaction generally was notachieved until the water content was reduced to'or below theoptimum water content as a result of drainage.The time requiredfor drainage is a function of the lift thickness and, therefore,where 95% and 93% compaction is required, lift thicknesses of8-in. andare recommended.Thethick loose lift inareas where 93% compaction is required was recommended based onthe fact that the average percent compaction of 93.0% was achievedfor the molecuttings (No Special Controls) test fill without thebenefit of extensive compactive efforts.
5.3 Determination of In-Place Dry Density The nuclear density meterprovides a much fasterdetermination of the field in-place dry density and water con-tent than the sand cone (SC).The accuracy of the NDM testsperformed in the gravelly sand and molecuttings was verifiedby comparing the results of adjacent NDM and SC tests.5.3.1 Gravelly Sand Generally, two SC tests were performed adjacent totwo NDM tests on each lift of the test fill to com-pare the in-place dry density and water contentmeasured by each method.. The in-place water con-tent determined by the sand cone versus nuclear den-sity meter is plotted on Fig. 9.The data indicatethat both methods measure essentially the same watercontent at values less than 8% and, as the water con-tent increases, the NDM measures a lower value thanthe SC. As a result, a correction was applied tothe water content measured by the NDM to compute thein-place dry density... A plot of sand cone versusnuclear density meter determined in-place dry densityis shown on Fig. 10.The correlation of the densi-ties determined by each method was considered to bepoor.The correlation may have been improved ifmore frequent moisture checks had been performed dur-ing construction of the test fill.5.3.2Molecuttings Twelve-inch-diameter sand cone tests were performedin the molecuttings to reduce the effects that themaximum particle size and percentage of materiallarger than thesieve would have on in-place drydensity determination. The in-place dry density andwater content determined by the SC test was comparedto the results from adjacentNDM tests.Comparison of the results indicated the water contentdetermined by the NDM averaged 1.7% higher than thatdetermined by the sand cone.The 1.7% difference inwater contents was confirmed by performing water con-tent checks at random NDM test locations. A 1.7% biascorrection was applied to the water contents determinedby the NDM. A plot of sand cone determined water con-tent versus nuclear density meter water content (with a1.7% bias correction) is presented on Fig. 11.
The plot shows there is a good correlation betweenthe sand cone and nuclear density meter (after biascorrection) water content determinations.A secondwater content check was made on molecuttings. afterthe test fill was completed which indicated thatthe bias had increased to 2.5%.Because the watercontent bias changed significantly within a periodof two weeks periodic checks of the bias arerecommended.The in-place dry density determined by the sand conetest and the 8-in. NDM test after correction for thewater content bias is plotted on Fig. 12.The soliddots and dashed circles represent in-place dry den-sity measurements at water contents less than 5% andgreater thanrespectively.The data indicatethat there is good correlation of dry densities deter-mined by both methods at water contents less than 5%and that the SC measured higher dry densities thanthe NDM at water contents above 5%.For this testfill the SC tests performed in molecuttings compactedat water contents above 5% are not considered validfor the reasons presented in the following discussion.When the molecuttings were placed at water contentsabove aboutthe compacted surface would exhibit aspongy behavior when one walked across the surface.The degree of sponginess increased as the moistureincreased above the optimum water content.Thesponginess is believed to be caused by water and airpore pressures. The net effect was that as the sandcone hole was excavated the pore pressures at thewalls of the hole were relieved by the walls movinglaterally into the hole until an equilibrium of thepore pressure at the walls of the hole was reached.Thus, by the time the volume of the hole was measureda significant decrease in the volume of the hole hadoccurred but the quantity of soil excavated was fromthe original volume.The result was that the dry soilexcavated was divided by awhich re-sulted in an inaccurately high computed dry density.The SC and NDM test results indicate that the NDM canbe used to determine the in-place dry density and watercontent of molecuttings. The water content bias shouldbe checked periodically to account for changes thatoccur in the molecuttings. Details of a recommendedplacement procedure arepresented in Appendix A.
5.4 Determination of Percent Compaction The field and laboratory data indicated the nuclear densitymeter could be used to determine the in-place dry density afterthe appropriate water content bias had been determined for themolecuttings being tested.The preferred field procedure for determing the percent com-paction of compacted soil is as follows:1.Gbtain a one-point sample of the soil before compaction.2.Perform the' one-point compaction test in the lab anddetermine the maximum dry density from a family ofcurves.3. Perform the in-place dry density of the compacted liftusing the nuclear density meter at or near thelocation of where the one-point sample was taken.This procedure can be used for the molecuttings if at leastthree nuclear density meter determinations of the in-place drydensity are made. The average of the three tests should be usedto represent the in-place density for computation of the percentcompaction. The above procedure will reduce the effect that minorin the character of the molecuttings will have on thein-place dry density determination.The use of a standard laboratory compaction test or one whichwas slightly modified was considered the best method of deter-mining the maximum dry density of the molecuttings.The ModifiedAASHG Compaction Test, ASTM D1557, permits the use of minusmaterial to be compacted in 6-in. molds.Grain-size analysesperformed on molecuttings indicate that nearly 50% of the sampleis retained on thesieve, and, as a result, the materialpassing thesieve would behave much differently than thetotal sample during compaction. A sample of the molecuttings thatwould represent the compaction behavior of the material was con-sidered possible if the amount of coarse material removed waslimited to about 20% by weight of the total sample.This couldgenerally be achieved by removing material retained on thesieve.For the test fill the laboratory compaction used was ASTMD1557, Method C, except the plusmaterial was removed.Because this compaction test, as modified above, was used for thetest fill and gave reasonable results its use is recommended forperforming laboratory compaction tests on the molecuttings.
5.5 Water Content Control The laboratory compaction curves for compaction tests per-formed on samples of molecuttings show a sharp peak in dry densityat the optimum water content, Fig. 6.The dry density drops asthe water increases or decreases from the optimum value.Thelaboratory data show that small variations in water content sig-nificantly affect the degree of compaction that can be achievedin the molecuttings. This behavior was also observed duringplacement and compaction of the molecuttings in the test fills.In the test fill where placement of the molecuttings was con-trolled, the required percent compaction generally could only beachieved by controlling the water content, by either wetting ordrying, of the molecuttings.The most efficient compaction of themolecuttings was when the water content was from about 4 to 6%.Therefore, the water content of the molecuttings should notdiffer from optimum by more than +for most efficienttion.
TABLES TABLEOF FIELD DENSITY TESTS.GRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNo.SampleNo.PercentND-1One-point120.9ThiscolumnND-2samplesnot123.7doesnotap-ND-3obtained121.1plyforcompac-SC-1118.1tiontestper-formedusing2SC-111.19.7120.9123.0115.0ASTM93.5ND-24.810.0116.8120.5117.1Method D97.2SC-39.49.0120.1123.0120.397.88.19.2117.9122.0119.5N.A.13.0122.31 2 2 . 3119.23ND-1One-point123.0SC-2samplesnot126.0ND-3obtained121.4122.5N.A.I5.2I115.5122.1121.548.54.9117.8125.5119.194.98.54.9117.8125.5120.596.05.07.4119.1124.0124.1100.05.0.7.4119.1124.0118.895.8ND-55.8I7.0121.5126.0119.094.4NOTES:One-point compaction sample performed by Pittsburgh Testing Labs.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLEOF FIELD DENSITY TESTSGRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2NO.SampleNo.One-PointLaboratoryMaximumDry DensityIn-PlaceDrDensitypcfPercentCompactionPercentMaterialWaterContent%DensityForMaterial4.89.7124.5125.0125.5100.44.89.7124.5125.0123.899.05.810.3123.1124.0120.997.513.09.3126.4127.0124.998.013.09.3126.4127.0121.395.53.910.0122.3123.2117.895.613.28.4126.0127.0118.793.513.28.4126.0127.0125.799.09.17.6123.3126.5123.097.29.17.6123.3126.5126.699.75.96.8120.5126.5122.596.85.9120.5126.5123.897.910.77.8121.0124.8121.697.410.77.8121.0124.8123.298.711.37.6121.5125.8121.996.9ND-lOne-point119.6SC-2samplesnot118.9ND-3obtained120.2SC-4118.8IN.A.13.8117.9120.9116.2.NOTES:(1) One-point compaction sample performed by Fittsburgh Testing Lab.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.(3) Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geo technical Engineers Inc.Project 76301July 12, 1979 PLACEMENT)FILLTABLEOF FIELD DENSITY TESTSQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNO.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density, pcfPercent%PercentMaterialWaterContento0DryDensityTotalCorrectedForMaterial1ND-12One-pointN.A.145.5N.A.N.A.ND-13samplesnotN.A.144.0N.A.N.A.ND-14obtainedN.A.142.6N.A.N.A.ND-15N.A.146.9144.5N.A.2ND-810.85.1145.4151.0150.0146.997.324.95.1146.0151.5149.5140.993.0(1)7.3.7153.0161.5152.4150.5158.498.43ND-1011.44.6145.9152.0143.1139.091.4ND-1110.4.14.4144152.5151.8145.5152.4.150.7142.8149.898.293.999.24ND-l7.35.0151.2154.0149.4147.495.78.24.6148.3154.0148.3145.994.76.84.3144.9142.792.6.149.797.2NOTES:One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.Project 76301July 12, 1979 MOLECUTTINGS (CONTROLLED PLACEMENT) TEST FILLQUARTZITE MOLECUTTINGS STUDYTABLEOF FIELD DENSITY TESTSSTATIONPage 2 of 2LiftNo.SampleNo.One-PoirMaximumDensityIn-PlaceDensity,MaterialWaterContent%DensityCorrectedForMaterial5ND-85.64.9148.7155.0150.6149.17.74.1146.5155.0148.0145.714.54.7146.0149.4145.0.162.3160.66ND-416.94.0146.0155.0152.6146.0ND-57.84.5147.9153.0150.2148.17.54.2148.3154.0152.3150.4148.3154.07ND-412.54.9145.21 5 1 . 0147.1143.1ND-512.25.0147.5152.0149.5145.9ND-610.44.6146.3152.0147.6144.48ND-lOne-point146.0N.A.ND-2samplesnot146.5N.A.ND-3obtained146.1N.A.PercentCompaction96.294.094.895.596.897.794.896.095.0N.A.N.A.N.A.NOTES: (1) One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.July 12, TABLE 3OF FIELD DENSITY TESTSMOLECUTTINGSSPECIAL CONTROLS) TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATION 2LiftNo.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density,PercentCompactionPercentMaterialWaterContent%DensitySampleCorrectedFor +Material1ND-4One-point146.3N.A.ND-5samplesnot142.4N.A.ND-6obtained145.5N.A.ND-7149.1149.1N.A.2ND-412.34.6147.7155.0149.4145.794.0ND-510.65.8149.0152.0145.8144.595.1ND-614.55.5149.6152.0145.8142.393.6SC-712.34.6147.7155.0157.8154.591.03ND-56.06.7147.0151.0143.7141.793.8ND-69.26.2147.8151.0141.9.138.591.74ND-l10.66.5148.8151.1144.7141.193.3ND-215.56.6146.0151.0143.0137.190.85ND-l12.34.9148.9153.0150.9147.596.4ND-212.35.0148.1152.0152.2149.098.0ND-324.84.7147.7153.0140.5129.084.36ND-523.54.3153.3156.0154.2147.794.7ND-68.53.6145.1153.0145.1142.393.0ND-79.45.6153.6155.0143.3140.090.3Geotechnical Engineers Inc.Project 76301July 12, 1979 3OF FIELD DENSITY TESTS.SPECIALTEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2CompactionLaboratoryMaximumDryDensityIIn-Place Dry Density, pcfPercentCompaction%WaterContentDryDensityCorrectedForMaterial78ND-7ND-8ND-9ND-1ND-2ND-35.14.07.5One-pointsamplesnotobtained3.13.43.9141.2140.1143.6149.0148.0151.0140.0139.2148.8144.4125.0144.3138.1137.7146.6N.A.N.A.N.A.92.793.097.1N.A.N.A.N.A.Geotcchnical Engineers Inc.Project 76301July 12, 1979 4OF FIELD DENSITY TESTS STRATIFIED MOLECUTTINGS AND GRAVELLY SAND TEST FILLQLJARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 1LiftNo.SampleNo.One-PairnLaboratoryMaximumDryDensityDensity, pcfPercentPercent+Material%WaterContentDryDensityTOY-11CorrectedForMaterial3ND-715.05.7149.3153.0148.8144.194.2ND-812.26.0148.8152.0145.9141.893.35.6118.3125.0114.3N.A.91.4ND-42.7122.2124.0108.1N.A.87.2ND-53.0115.1123.0108.2N.A.88.0ND-64.9116.9124.5N.A.88.85ND-410.44.3145.7151.0151.3148.5ND-516.33.8144.8153.0138.1130.8N.A.N.A.123.31.27.5123.8N.A.97.17.2123.3127.5121.1N.A.95.0ND-36.8118.8124.5119.3N.A.95.8ND-48.3120.3124.0119.6N.A.96.57ND-104.82.7137.5148.0140.2138.493.58ND-4Onepoint147.3N.A.N.A.ND-5samplesnotobtained140.8N.A.N.A.NOTES :construction or Lift.(2)Values represent percentmaterial.(3)Nuclear density probe may have penetrated gravelly sand layer below.(4) One one-point compaction sample obtained for SC-1 and ND-2.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLE 5SUMMARY OF PLATE LOAD TESTS RESULTSQUARTZITE MOLECUTTINGS STUDYSTATIONLoadNo.SoilAtTestSoilModulus,psiAveragePercentCompaction1R e m a r k sVirginReload1GravellySand97.12Mole92.6(NoSpecialControl)3StratifiedAve. PercentMoleCuttingsandGravellyCompaction93.7Sand4Mole95.3(ControlledPlacement)5MoleCuttings(NoSpecialPerformed13daysafterControl)PLT-2Geotechnical Engineers Inc.Project 76301July 11, 1979 FIGURES PLAN VIEWTEST FILLSic ServiceofProjectStudyMolecuttingsPLT-3GravellycuttingsSandStratified Mole-cuttings andGravelly Sand(ControlledPlacement)LT-5PLT-4PLT-1PLT-2cuttings(No SpecialNot To Scale PROFILE OF GRAVELLY SANDTEST FILLSteel PlateLift 7 Ave.Comp. = 97.5Lift 6 Ave.Comp. = 97.0Lift 5 Ave.Comp. = 98.1. Lift 2Ave.% Comp. = 97.4Lift 1 Ave.Corns. = 99.0Lift 4 Ave.= 96.2Lift 3 Ave. % Comp. = 100.6Scale:= 2.5'1. One-point compaction samples not obtained.Average percentcompaction is based on maximum dry density provided by PTL.PROFILE OF MOLECUTTINGS(CONTROLLED PLACEMENT) TEST FILLSteel PlateAve.Comp. = 95.3Lift 6 Ave. %= 96.7Lift 5 Ave.Comp. = 95.0Lift 4 Ave. % Comp. = 95.1Lift 3 Ave.= 95.7Lift 2 Ave.96.2Lift 1 Ave.Comp. = N. A.Scale:= 2.5'Molecuttings l -PROFILE OF TEST_ FILLSProject 7630111, PROFILE OF MOLECUTTINGS(NO SPECIAL CONTROLS) TEST FILLLift 1 Ave.Comp. = N.A.Scale:= 2.5'PROFILE OF STRATIFIED MOLECUTTINGSAND GRAVELLY SAND TEST FILLServiceofIMolecuttingsIPROFILE OFFILLSStudyProject11, 19g .Steel Plate (PLT-2and 5)Lift 8 Ave.=Lift 7 Ave.= 94.3Lift 6 Ave.Comp. = 92.7Lift 5 Ave.Comp. = 92.9Lift 4 Ave.Comp. = 92.1Lift 3 Ave. % Comp. = 92.8Lift 2 Ave.Comp. = 94.7.Steel Plate (PLT-3)Lift 8 Ave. % Comp. = N.A.Lift 1 Ave.= N.A.Scale:2.5' U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDRCMETER6432IofLabs.Pro-iIGrain-size analyses per 'formed,..COBBLESCOARSEIFINECOARSEMEDIUMIFINEWINCHESTERMASSACHUSETTS3 4 6GRAIN SIZE MILLIMETERSSIZEQuartziteMolecuttingsGRAVELLY SANDStudyITEST FILLIIi11, 1979 NOTE: 1. Compaction test performed inwithC,the plusmaterial. was discarded and no limitationplaced on the percent retained on thePublic Service Company ofNewhireQuartzite MolecuttingsStudyProject 76301. COMPACTION CURVESMolccuttingsJuly 12, 1979Molecuttings- V W - -ControlledMolecuttings(No Special Controls)(Controlled Placement)Lift 4s = 100%-Gave = 2.83 (De152..02468IOWater Content, U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETERGRAIN SIZE MILLIMETERSCOBBLESSANDFINEGRAIN SIZESAMPLES OFMOLECUTTINGSQuartziteMolecuttingsstudyICOARSE FINE COARSEMEDIUMWINCHESTER . MASSACHUSETTSanalyses performedusing successive elutriation.MOLECDTTINGSMOLECUTTINGSLIFT 2LIFT 4I -I - -500100505I0.561(No Special Controls4 32I820 30 40 50 70200MOLECUTTINGS(Controlled Placement)(ControlledPlacement)0.050.001
.MOGravelly Sand302520151050PERCENT COMPACTIONVERSUS9092349698100Percent ofof Modified AASHO, %NOTES: 1. Modulus of elasticity computed using theory of elasticityfor semi-infinite, isotropic soil.2.Modulus of elasticity value plotted is minimum value fromvirgin loading curve.3.Percent compaction is the average percent compaction ofthe first three layers of soil under the plate.4.Percent compaction the average percent compaction of twolayers of molecuttings and one layer of gravelly sand.5.Range in percent compaction is estimated.See discussion in text.Public Service Company ofQuartziteMolecuttingsStudy76301 4.06.08.014.0Nuclear Density Meter Determined In-Place Water Content,WATER CONTENTSAND CONE VSDENSITY METERGRAVELLY SANDJu98 . 06 . 0Estimated Line ofGravelly SandBest Fit Gravelly Sandr11114116118122124126Density Meter Determined In-Place Dry Density, pcfNOTES: 1. In-place dry density includes plusmaterial. .2.In-place dry density based on 8-in. deep nuclear test.Densitieshave been corrected for water content bias according to plot ofversusnuclear for gravelly sand:conedevice3.Cone and Nuclear Density Meter determinations were performedto each other (about 6-12 in. apart).SAND CONE VS NUCLEAR DENSITY METER DET.DRY DENSITYGRAVELLY SAND10.-.--.----PublicCompany of.Elcwi L-CIIIIIQuartzitestudyProject 76301 Nuclear Density Meter DeterminedWater Content,(after bias was corrected)8 . 07 . 06 . 0Molecuttings3.04.05.06.07.08.0NOTES: 1. In-place water content is baseddeep nuclear test.
135145150155160Nuclear Density Meter Determined In-Place DryDensity,NOTES: 1. In-place dry density is uncorrected for the plusmater2..except where noted.3.Water content of Sand Cone was greater than 5.0%.4.In-place density is based on 4-in. deep nuclear test.MolecuttingsPublic Service Company ofSAND CONE VS NUCLEARiSITY METER DET. IN-PLACEDRY DENSITYMOLECUTTINGSI.QuartziteMolccuttingsStudyProject 7630111, APPENDIX ASAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35in.75-1032-O22-o10-O2.The uniformity coefficient,should be notless than 5.B.PLACEMENT1.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 95% of maximum dry densityas determined by ASTMwith exceptions fortesting noted in Section C.2.2.The water content of the molecuttings should be atoptimum1% during placement. The water contentduringof quartzite molecuttings shouldbe stockpiled or otherwise treated to reduce thewater content to less than 6%.If the water contentis less thanthe addition of water during com-paction will be necessary if satisfactory compactionis to be achieved.3.Molecuttings should not be placed in direct contactwith pipes, culverts, or other structures sensitiveto abrasion and/or high point loads.4.The pore fluid of the molecuttings is brackish and,as a result, the resistivity of the muck is likelyto be below the minimum limit of 10,000United Engineers is to develop recommendations forplacement of the molecuttings in areas when highresistivity of backfill material is required.
C.TESTING AND FIELD CONTROLDue to anticipated variations in rock type thecuttings should be monitored daily by determining thegrain-size distribution, water content, and rock typefor at least one typical sample.The grain-sizeanalysis should be performed by using a wet sievingtechnique and every tenth test should be performedby using the elutriation method, without pre-dryingof the sample. The frequency of testing may be re-duced in time after those testing become familiar withthe material and thus capable of judging when thematerial is or is not acceptable.a.If the percent passing thesieve materialis greater thanthe material should not beused.b.If the water content is greater than 1% aboveoptimum, the molecuttings should be stockpiledor treated to reduce the water content to optimum.2.A family of at least three compaction curves should bcdeveloped using ASTM D1557, Method C, except that theminusmaterial shall be used. Each compactioncurve should be accompanied by a grain-size analysis.Additional compaction curves should be performed onceevery 7,500 yards or earlier if visual changes in themolecuttings grain size is observed.3.A bag sample of the molecuttings should be obtainedafter the loose lift has been placed and before com-paction begins. The sample should be large enough toperform a laboratory one-point compaction test and tomeasure the percent material retained on the l&inchsieve.4.Separate the plusmaterial and calculate itspercentage by weight of the entire sample.5.A one-pointtest should be'performed on thebag sample of molecuttings in accordance with ASTMD1557, Method C, except that the minussievematerial shall be used.The maximum dry density for this sample, yd , is determined by plotting thepoint dry on the family of curves and inter-polating the maximum dry density for the minusmaterial.6.The in-place dry density should be determined by per-forming at least three nuclear density meter tests.The average dry density should be used to computethe percent compaction.This method should reduce theeffects of sharp variations in the molecuttings on thein-place dry density determinations.a. The water content bias for the nuclear densitymeter should be corrected for use in molecuttings.The water content bias should be checked weekly.7.The percent compaction is determined by dividing thecorrected in-place dry density by the laboratory maxi-mum dry density as determined in 6. above. A formulato compute the corrected in-place dry density, tocorrect for the quantity of plusmaterial, ispresented below. = 1-Rwhere= corrected in-place dry density for theminussieve material= average in-place dry density determinedby using nuclear density meter= unit weight of waterG = specific gravity of molecuttingsR = percent, by weight of the total sampleretained on thesieveThe percent compaction is computed as follows:Percent Compaction P(%) =x 100.= Maximum dry density of minusmaterialdetermined in Step 5. from the family ofcurves and the one-point compaction.YND NONSAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35100-1775-10No. 2022-o10-O2.The uniformity coefficientnot be lessthan 5.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 93 of maximum dry density asdetermined by ASTM D1557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Molecuttings can be sandwiched between presently ac-cepted gravelly sand structural fill. Whencuttings and gravelly sand are alternated in the back-fill, the following limits are recommended.a.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 93maximum dry densityas determined by ASTMb.Gravelly sand should be placed in accordance withthe present specification for structural fill (i.e.,8-in. loose lifts compacted to 95% of ASTM3. The water content of theshould beoptimum1% during placement if no gravelly sand layersare present. When the molecuttings and gravelly sandare placed in alternating layers, the water content ofthe molecuttings may be permitted to be as high as 2%above optimum.If the water content of the molecuttingsexceeds the suggested limits of water content, thecuttings should be stockpiled or otherwise treated toalter the water content.If the water content is low,say 2 tothe addition of water during compactionmay be necessary to achieve satisfactory compaction.
RANDOM FILLA.MATERIALThe molecuttings to be used asFill should complywith the present specification as described in Specification No.9763-8-4, Section 3.2.2 dated September 27, 1974.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 90 of maximum dry density asdetermined by ASTM Dl557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Although limits on the water content of thecuttings are not necessary, the most efficient com-paction will occur at optimum water content1%.C.TESTING AND FIELD CONTROLTesting and field control for use of molecuttings as Ran-dom Fill should be the same as outlined for Safety-Related areaswith the following exceptions:The gradation of the molecuttings should comply withpresent specifications for Random Fill.No limit on the water content of the molecuttings isrecommended.The maximum permissible water contentin the field will be dictated by the ability toachieve the required percent compaction.
APPENDIX
APPENDIX BPLATE LOAD TESTB-l PurposeThe plate load tests were performed to determine the de-formation characteristics of gravelly sand and molecuttings.The results of the plate load tests provided the basis forcomparison of the two materials and to determine the effectthat percent compaction has on their deformation characteristics.. B-2 ProcedureFor each test a 24-in. -diameter hole was excavated to adepth of 12 in., except for test PLT-3 which was 6 in. deep.An -diameter, thick steel plate was placed on athin layer of liquid hydrous stone which was placed directlyon the bottom surface of the test hole. Additionalsteel platesandin diameter were placed in apyramid arrangement on top of theplate.After the hydrous stone and plates were in place, theplate was loaded by a hydraulic jack reacting against the under-side of a loaded, flat-bed trailer, as illustrated in Fig. B-l.The loads were measured using a calibrate pressure gage.Deformations of the plate were measured using three dialindicators attached to a reference beam as illustrated in Fig.B-l. The dial indicators were graduated to mm. The ref-erence beam supports were separated from the center the plateby about 72 in., which was a sufficient distance for deflectionsunder the supports to be negligible during loading of the plate.The loading sequence for each test was as follows:1.Applied load to develop contact stress of 4 tonsper square foot (tsf) in four equal increments.2.Unload to zero load in two equal increments.3.Repeat load-unload cycle to 4 tsf.4.Load to develop contact stress of 12 tsf in sixequal increments.
EDS-2-5.Unload to zero load in three equal increments.6.Repeat load-unload cycle to 12 tsf two more times.Each loading or unloading increment was held constantuntil the rate of deformation of the plate was less than.001The air temperature when the plate load tests were per-formed was aboutF.B-3 ResultsThe load versus displacement curves for the five plate loadtests are illustrated in Figs. B-2 through B-6.The slope ofthe virgin load curve was generally straight except for testPLT-2 and PLT-3 where slight curvature was observed.The slopeof the reload curves were much flatter than the virgin curveand the slopes of the repeated reload-unload cycles were parallelas would be expected.Values of Young's Modulus, E, were calculated from the re-sults of the plate load tests using elastic theory.The solutionfor the settlement of a loaded, rigid circular plate on anelastic half space is as follows:where s = settlementq = average stress on the plateP = load on the plateD = diameter of the plate= Poisson's ratioI = influence factor =E = Young's ModulusAssuming a value v = 0.3 and rearranging to compute E, yields:The modulus calculated is the average modulus within the zoneof significant stress which for anplate would extend between18 to 36 inches beneath the plate.The moduli calculated using this method are presented in TableFor each test tangent moduli were calculated using the straightsegments of the load and reload curves.
PLATETEST EQUIPMENTWINCHESTER .Project 76301Julv 12, 1979PublicofNew HampshireReaction Structure (Loaded Flat-bed Trailer)\ LiquidHydrousStoneBearing PlatesDial IndicatorBeamRefBeamSupportof Test FillNOTE: 1.Depth for PLT-3 was about 6-in.Schematic Illustration of Plate Load Test Equipment--(Not ToDialSteel Bearing PlateDial"Ear" Welded To Bearing PlateDial indicatorsandmonitored displacement of "ears" attachedto circumference of bearing plate.Plan---Locations of Dial Indicators(Not ToStudy 6 . 07 . 08 . 002.06.08.0. 10.012.0Vertical Stress. tsfDate Performed:June 7, 1979By:Fisher/R. GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONPLATE LOAD TESTGRAVELLY SAND...11I 802.04.06.010.012.0icof.QuartziteProject 76301StudyPLATETEST PLT-211.Vertical Stress, tsfDate Performed:June 14, 1979By:GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONCON.)
41.2.3.04.06.08.0Vertical Stress, tsfDate Performed:June1979By: W. Fisher/R. GardnerPlate Diameter:Company of10.012.0VERTICALVSMolecuttingsStudyPLATE LOAD TEST PLT-3ST.GR.76301i 04 . c04.06.08.010.012.cVertical Stress, tsfDate Performed:June 18, 1979By:Fisher/R.GardnerPlate Diameter:MolecuttingsPLATE LOAD TEST PLT-4. . . . --a.---1.02.03.0DEFORMATIONStudy 02.04.06.08.010.012.0..Vertical Stress, tsfDate Performed:June1979By:FisherPlate Diameter:- -.STRESS VSDEFORMATIONPLATE LOAD TEST PLT-5MOLECUTTINGS -(NO SP. CON.-July 11,g .1 . 0.2 . 04 . 05 . 06.07.0IIIIIQuartziteStudy TABLESUMMARY OF FIELD DENSITY TESTSPageLiftSampleOne-PointCompactionLaboratoryIn-Place Dry Density, pcfNo.No.PercentWaterMaximumTotalCorrectedCompactionMaterialContentDensityDry DensitySampleForMaterialoa00%
UPDATED FSARAPPENDIX 20GEOTECHNICAL REPORT DISCUSSION OF DERIVATION OFCOEFFICIENTS OFREACTIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
March 22, 1978Project 77386File No. 2.01017 MAIN STREET. WINCHESTER. MASSACHUSETTSMr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th Floor.Manchester, NH 03105
Subject:
Discussion of Derivationof Coefficients ofReaction
Dear Mr.In the following we describe some techniques that we havedeveloped to convert the moduli obtained from triaxial tests tomoduli ofreaction for various loading conditions. Wepresent this information to complement various telephone con-versations with D. Pate1 ofComputation of Coefficients ofReactionThe coefficient ofreaction,
represents soildeformation, due to pressure acting along a boundary surface,as if the soil were composed of independent springs, each repre-senting a unit of area with a spring constantThe springconstant is defined as a pressure divided by a displacement.Such a representation is convenient for analytical purposes butneglects the influence of adjacent loaded surface areas on thedisplacement of any given point on the boundary surface.Thus,the coefficient ofreaction is not a unique number foran elastic material but is a function of the size of the loadedarea, the pressure distribution, and the geometry ofmaterial.For a soil, the modulus ofreaction is also dependent onthe method or sequence of loading, i.e., the stress path.On the basis of the theory of elasticity, wecomputedcoefficients ofreaction for the structural backfill andthe sand cement for three geometries of loading using the modulusof elasticity and Poisson's ratio data obtained in the triaxialtest results. The geometries of loading studied are illustratedin Figs. 1 through 9 and are as follows:
Mr. JohnMarch 22, 19701.Circular or square footing subjected to vertical load.2.Pressure inside a cylindrical cavity in the soil massassuming a plane strain condition.This istive, for example, for the loading produced by thermalexpansion of the cross section of a buried pipe.3.Pressure inside a cylindrical cavity with simultaneousapplication of a vertical surcharge, p, and a horizon-tal pressure,This loading is an approximate re-presentation of the placement of fill over a buriedwhich deforms to produce an increased lateralstress around the pipe.A plane strain condition was.assumed.The modulus of elasticity and Poisson's ratio used in the compu-tations are strain dependent and were selected for the average strainin the region of the soil mass that contributes most to the displace-ments, namely, within a distance of one diameter from the pipe and onefooting width below the footing base. These strains were correlatedwith the displacements which, in turn, were expressed in terms offooting settlement divided by6/B, or in terms of thediameter strain of the pipe,In Figs. 1 through 9, the values ofthe coefficient ofreaction are plotted as a function of (T/Borand confining pressure. Confining pressure is to be taken asthe effective overburden pressure computed at the elevations shown inthe figures. An exception to the above procedure is that for the sur-charge type loading, a constant Poisson's ratio of 0.3 was used.The elastic modulus E and Poisson's ratio v used as a basis forthe coefficient of reaction computations were obtained fromtriaxial compression tests in which the minor principal stresses werekept constant and the major principal stress was increased monotoni-cally until the specimen failed. Such a stress path would be sufficientto determine E and v for an elastic material.However, soil is notelastic and E and v are dependent on the stress path or stress history.In particular, higher values of E would be obtained for repeated orcyclic loading. For the static load conditions, we feel that the valuesofreaction presented are reasonable estimates for the in-situloading conditions. As shown in the next section, the values comparewell with values given in published literature.We recommend, however,that when these values are used, sensitivity analyses should be made toassure that the designs are safe for a range 25% above and below thegiven values.Comparison With Published Coefficients ofReactionThe coefficients ofreaction obtained from thetestswere compared with data presented by K. Terzaghi in the paper entitled PrincipalGC/SJP:msEncl.ccR.YAECD.A. Desai,D. Patel,Mr. JohnMarch 22, 1978"Evaluation of Coefficients ofReactionGeotechnique,vol. 5, 1955, pp. 297-326.For shallow footings the vertical coefficient ofre-action for a one square foot plate, is estimated by Terzaghito range between 300 and 1,000 ton/cu ft for dense sands, i.e., arange for x B of 4,000 to 14,000 psi. These values are intendedfor shallow footings,a typical depth of embedment, Dof 4ft, and for a width, B, of one foot.Thus, they areof confining pressures equivalent to a depth of 4.5 ft or about 4 psi.The coefficient of horizontalreaction is given byTerzaghi for a 1 sq ft vertical area at a given depth, and it isassumed to be proportional to the effective stress at that depth.For example, for dense sands at a confining pressure of 10 psi, arange ofof 7,000 to 14,000 psi is indicated..Thedata for structural backfill, for strains of aboutFigs. 1, 2, 4 and 5, agree with Terzaghi's data.No specific infor-mation on strain level is given by Terzaghi for his data, but heindicates that the data are applicable to a factor of safety againstbearing capacity failure that is larger than two.It is also implicitthat the factor of safety would not be much more than 2.Perhaps itlies in the range of 2 to 4.For such factors of safety, the resultsof plate load tests on sands (1 sq ft plate) would indicate typicalsettlements of 0.1 in. to 0.3 in., which would be equivalent to avertical strain on the order of 1% in the soil adjacent to the plate.Thus, the data for the structural backfill obtained from the triaxialtests correspond to coefficients ofreaction within therange given by Terzaghi.Sincerely yours,GEOTECHNICAL ENGINEERS INC.Steve J. PoulosPrincipal FIGURES ReactionGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386Public Service Company ofNew Hampshire=March 13, 3.978Fig. 1SETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt462347Sand and Sand-CementBackfillPRESSURE ONBACKFILL90% COMPACTION ReactionSETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt B/2)..4IO'986544567 8 910234568sProject,.77386FOOTING PRESSURE ONSTRUCTURAL BACKFILL95% COMPACTIONMarch 13, 1978Fig. 2Public Service Company ofNew HampshireGeotechnicalInc.Winchester, M a s s a c h u s e t tSand and Sand-CementBackf ill 96SmSETTLEMENTk9765= EFFECTIVE VERTICASTRESS AT DEPTH445679102346789100Public Service Company ofReactionFOOTING PRESSURE ONNew HampshireSand and Sand-CementSAND-CEMENTBackf illBACKFILLEngineers Inc. ,Winchester,MassachusettsProject 77386March 13, 1978Fig.
ReactionSand and Sand-CementBackf illEngineers IncWinchester, MassachusettsProject 77386Public Service Company ofNew HampshireMarch 13, 1978Fig. 4INTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILLCOMPACTIONIO'9765976541456 7 8 91023456 7 65489467 8 9102346ReactionProject 77386March 13, 1978Fia. 5Sand and Sand-CementBackf illINTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILL95% COMPACTIONPublic Servide Company ofNew HampshireGeotechnical Engineers Inc.Winchester,MassachusettsEFFECTIVE VERTICALSTRESS AT DEPTH Z2U=I IO986987463456 7 8 91023456 7 8Public Service Company ofNewGeotechnical Engineers Inc.Winchester,MassachusettsReactionSand and Sand-CementBackfillProject 77386March 13, 1978Fig. 6= EFFECTIVE VERTICALSTRESS AT DEPTHSAND-CEMENT BACKFILLINTERNAL PRESSUREPIPE BURIED INDISPLACEMENT ReactionDISPLACEMENT=98765= EFFECTIVE VERTICALSTRESS AT DEPTH4452346 7 8 9 0 0SURCHARGE PRESSURE ONPIPE IN STRUCTURALBACKFILLCOMPACTIONMarch 13, 1978Fig. 7Project 77386Sand and Sand-CementBackf illPublic Service Company ofGeotechnical Engineers Inc.Winchester, MassachusettsNew Hampshire 4567 8 910234564ReactionSand and Sand-CementBackf illProject 77386BACKFILL'95% COMPACTIONMarch 13, 1978Fig. 8ON PIPE IN STRUCTURALSURCHARGE PRESSUREInc.DISPLACEMENT= EFFECTIVE VERTICALSTRESS AT DEPTH ZPublic Service Company ofNew HampshireWinchester, Massachusetts UPDATED FSARAPPENDIX 2PSTATION CONTAINMENT AIRCRAFT IMPACT ANALYSISThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
FSARAPPENDIX 2P STATION CONTAINMENTAIRCRAFT IMPACT ANALYSISPrepared byUNITED ENGINEERSCONSTRUCTORS INC.OCTOBER 1975PUBLIC SERVICE COMPANY OF NEW HAMPSHIRESEABROOK, NEWHAMPSHIRE CONTENTSABSTRACTl-ll-ll-12l-14l-15FSARCONTENTS1.0 Structural Analysis ofStation Containmentfor Aircraft Impact l-l1.1Introduction ------------------------------1.2Forcing Function for Impacting Aircraft1.3Behavior of Containment -------1.4Response of the Enclosure Building -----1.5Shear Capability of the Containment ----1.6Requirements to Prevent Perforation ----1.7Conclusions1.8References for Section2.0 Fire Hazard Analysis ofStation 2-l2.1CombustibleVaporProduction 2-22.2FireAnalysis2-22.3Evaluation of Various Safety Related Areas 2-42.4Hazards from Smaller Aircrafti 2-62.5Conclusion2-72.6References for Section2-7l-18 SBFSARABSTRACTResults are presented which verify the adequacy of thecontainment to resist the impact of an FB-111 type aircraft.Includedis a description of the dynamic forcing function, the elastic-dynamicanalysis, the elastic-plastic analysis, an estimate of reinforcementand liner strain and a verification of the punching shear capabilityof the containment.It is shown that there existsmechanism by which spilledfuel from the impacting aircraft can access theThe ensuingfire is, therefore, postulated to start in thevicinityexternal toenclosure and it is demonstrated that these externalfires do not, in any way, inhibit or handicap the safe shutdown cap-ability of the plant following the postulated crash.It is concluded, that under the aircraft impact, the containmentstructure is able to withstand postulated impact and that the consequencesof the aforementioned fire hazard is mitigated by the inherent designfeatures ofStation.
1.0 STRUCTURAL ANALYSIS OFSTATION+2l-ldxFSARAIRCRAFT IMPACT1.1 IntroductionTheStation containment has been analyzed for the effects ofa-postulated impact by an FB-111 type aircraft with a speed atimpact of 200 mph.Based on the analyses performed;-theof the containment to withstand the postulated impact is verified.TheStation containment and enclosure building is describedin Section 3.8.1 of thePSAR. The FB-111 aircraft, the missilein the postulated73.5 feet long, has a wingspanoosition) of 70.0 feet and weighs 81.800 Dounds (See Reference 1).In order to perform the analyses,a force-time relationship isdeveloped from the mechanical properties of the impacting aircraft.An elastic dynamic analysis indicates that an elastic-plasticdynamic analysis is required to predict theresponse of thestructure.From this analysis of the structure,is madeof the strains experienced by the reinforcing bars and liner.Subsequently, an analysis is performed to verify the adequacy of thecontainment against punching shear and penetration.1.2 FORCING FUNCTION FOR IMPACTING AIRCRAFTThe time variation of the load on a rigid surface due to an impactingaircraft may be developed using the momentum principle.The governingequations which are used to determine thevariation of the forceexperienced by the target are (Reference 2):
FSARwhereR(t) is the force acting on the target (positive for compression),is the extent of crushing at any time t as measured from theleading edge of nose of the missile,is the load required to crush the cross section of the missileat any distance n from the nose,(positive for compression)is the mass density per unit length of the missile as a functionof the distance from the nose.These equations are used to determine the two unknowns, the crushinglength,and the reaction, R(t), as functions of time.Theinformation required to determine these variables consists of theinitial impact velocity, weight or mass distribution and crushingload distribution of the aircraft.The first equation is integrated numerically to obtain the velocitytime history. The reaction force is then determined from the secondequation.Figureshows three views of the FB-111 aircraft. Figurethe one dimensional idealized model of the same aircraft. Figure 2bdescribes the weight distribution for an FB-111 with a total weightof 81,800 pounds.The sketch and the weight distribution are obtainedfrom Reference 1.The particular configuration used is essentiallythe same as that summarized on P. 1.3.3 of Reference 1 with the wingstores and wing useful load removed.This configuration is consistenttheof the FB-111 at Pease AFB. The value of 81,800 pounds is thel-2 FSARweight before the airplane has warmed up and taken off.flights the aircraft would fly a mission and return to Pease AFB withapproximately 10,000 pounds of fuel.On this basis, the landingweight would be approximately 59,000 pounds.For those missionswhen the aircraft is flown with wing tanks the maximum take-offweight ispounds. The FB-lllis not allowed to land withfuel in these wing tanks; therefore in all cases the maximum landingweight is 81,800 pounds.Thus, the 81,800 lbs weight of the FB-111 used in the impact analysiswas the fully loaded FB-111 without wing tanks.This weight isconservatively large for any configuration of the aircraft flyingout of Pease AFB, but it was used because it represented a maximumupper bound on the weight of the FB-111 in the landing pattern.The exact crushing load distribution foran PB-111 is not available.The crushing load distribution shown onis arrived at byscaling the known values for ais demonstratedin this report that the peak value of the reaction is relativelyinsensitive to reasonable variations ofthe crushing load.Figure 3 shows the reaction-time relationship for the FB-111 strikinga rigid wall at an impact velocity of 200 mph. The peak value of thereaction is 8.2 x pounds. This peak value occurs when the wingstructure is in the process of collapsing.This peak reflects thel-3 PC8.5 x8.2 xpounds7.1 xpoundsFSARmass in the wing structurefuselage in the vicinitythenoted that the cross-sectional area overlargerthe area of fuselagesecondaryof 4.2106 pounds (atthe vicinity of the engines.The determination of the sensitivity of theto the magnitudethe crushing load is investigated bytheforvalues of one-fifth and fivethis crushing load.Theseresults are shown in Figure 4.From Figure 4,peak values of thereactions are:The peak value of the reactionrelativelv insensitive to variationsin' the magnitude of the crushing load, and the scaled value of PCjudged to give accurate results.1.3Behavior of Containment1.3.1 Elastic Dynamic Analysis For the elastic dynamic analysis, the finite element methodwas chosen as the analytical method, and a computer programfor axisymmetric structures subjected to arbitrary static anddynamic loads was used.(See Reference 3 for the basis of themechanics of the program.) Damping was not considered. Thus,the predicted structural response is slightly larger than thatwhich does occur.l-4 FSARTo accomplish the analysis, several assumptions were made.They are as follows:i)Theis fixed at the base of the cylinder.ii)Impact loads are uniformly distributed over the loadingzones.iii)In the axisymmetric analysis (impact at apex of dome), theloading zone is a circle with a radius of 52.77 inches andan area of 8748.3 square inches.iv)In the asymmetric analysis (impact at springline), theloading zone is a square,93.53 inches on a side and8748.3 square inches in area.v)The stiffness of the reinforcing steel is neglected; onlythe gross concrete volume is considered.The modulus ofelasticity was taken as 3.0 xin., Poisson'sratio was taken as 0.15, and the weight density wastaken as 150 pcf.vi)The effect of the enclosure building is neglected. Itcan be shown that the enclosure absorbs approximately 4%of the energy of the impacting aircraft.The containment structure is modeled with axisymmetric conicalshell elements, a plot of this model is shown in Figure 5.Two impact positions, the apex of the dome and the springline,are considered. The impact at the dome is uniformlydistributed over the first seven (7) elements, and the impactat the springline is uniformly distributed over the six (6)elements nearest to the springline.By means of a half-rangecosine series, the load at the springline is confined to al-5 FSAR6.18' arc.(30) terms were used to represent thisFourier series which is shown, normalized to 1.0, in Figure 6.Experience with loadings similar to the loadings here, hasdemonstrated that twenty (20) terms of the series were foundto be too few and ninetyterms were found toresultsvery close to those generated by thirtyterms.Selected maximum results for the axisymmetric and asymmetricanalyses are given in Tablesand l-2, respectively. Thesemoments will cause cracking of the concrete and yielding oftheTherefore, an elastic-plastic dynamic analysis isrequired.1.3.2' Elastic-Plastic Dynamic Analysis The procedure followed for the elastic-plastic analysis ofthe response of the containment under aircraft impact followsthat of(Reference 4). In this procedure, knowing theload-time relationship, the first natural frequency of thatpart of the structure participating in the energy absorption,and the allowable ductility ratio (defined as the ratio of themaximum deflection to the deflection at yield), the ratioof the maximum value of the load-timeto themaximum value of the resistance function can be determined. This1-6 SBFSARcan then be compared with the actual estimated maximum valuesof the load-time relationship and resistance function.The force-time relationship, given in Figure 3 is approximatedby a triangular load-time curve with the same total impulseand peak force.This ideal and the actual force-time relation-ships are compared in Figure 7 .It is assumed that a circularregion of radius "a" will participate in the energy absorption.The natural frequency, associated with this participatingregion, is estimated on the basis of the first naturalfrequency of a flat circular plate of radius "a" clamped atthe edges.The assumption of clamped edges, in that it givesa smaller period for the first natural frequency than in theactual case, is a conservative simplification. This followsbecause, in general the value of the maximum allowable forcingfunction decreases as the first natural period decreases (Ref. 4,p. 78, Figure 2.26).Conversely, ignoring the curvature isnon-conservative in that it gives an estimate*of the periodwhich is larger than the actual case.For small values of theradius "a", the curvature effect is minimal.All calculations are based upon thedome sectionconfiguration.The first natural frequency of a flat circularplate, clamped at the edge is:PX.17whereis therigidity and M is the mass density per unitsurface area (See, for example, Ref. 5).l-7 FSARthethick concrete plate with a Young's modulus ofpsi and a unit weight of 150 pounds per cubic foot,period is:sectioncracked section"a" in feet T15.94 x12.86 xUsing Fig, 2.26 of Reference 4the ratioas afunction of the radius of the participating material of thecontainment,can be determined for various values ofductility ratio.For the purpose of this investigation, two (2) ductilityratios, 3 and 10 are used. For plates and shells, the lowervalue is conservative, the larger value reasonable. Theresults of the calculations are shown in Table l-3 and Figure8.Although the range of Fig. 2.26 of Reference 4 islimited to aof 20, it can be observed that for aductility ratio greater than two and of 20, isgreater than unity. Therefore, the allowable peak force,F, can be than the maximum value of the resistance, Rm.1.3.3 Resistance FunctionIn the vicinity of the impact region, the response of thestructure is assumed to have the characteristics shown inFigureFor values of the force less than Rm, the displacements arelimited in magnitude even though the response may be inelastic.As the load reaches the valuethe deformations are ablel-8For3xthe 2+=FSARto become arbitrarily large, i.e.,the collapse load has beenreached.The collapse load for a concentrated load on acurved shell is not readily accessible.As a conservativeestimate, the collapse load for a flat plate with reinforcementthe same as the dome is used to estimate the collapse loadfor the shell..Expecting the yield line formation shown in Figureobservationsuggests that the clamped boundary condition case should beused. The value of the collapse load, Rm, is then (Referencewhereis the ultimate moment capacity and the notation + andrefers to the outside and inside reinforcement respectively.The ultimate moment capacities and collapse loads of thecontainment are:dome= 643 k-ft. /ft.651 k-ft./ft.springline= 1,235 k-ft./ftM-643 k-ft./ftAt the dome, the collapse load and peak load are approximatelyequal.However, from Figure 8 , the dynamic effect allowsthe structure to withstand loads in excess of the capacity.From Figurethe allowable load is 10% larger than theresistance or collapse load.Therefore,the apex will notl-9 FSARcollapse.Since the maximum load,less than thecapacity of the dome in the springline,collapse willnot occur at the springline.The dome will not collapse, under the applied load.1.3.4 Estimation of Rebar and Liner StrainsWhile plastic analysis techniques are useful for finding collapseloads, they cannot be directly used to find the strains anddisplacements corresponding to collapse loads.However, a procedure making use of the ductility ratio can beused to approximate the maximum strains in the structuresubject to dynamic loading when nonlinear material behavioris encountered.This procedure is described below.A typical load-displacement curve for reinforced concretesection is shown in Figure 10.This curve is linear up to theload causing crackingafter which a straight line ofsomewhat flatter slope is obtained until the loadisreached which causes yielding of the steel.Any increase in load beyondcauses the displacement toincreasedisproportionately.Further increase in load causesextensive displacements to occur,resulting in eventual collapse.This actual behavior of the structure was idealized as shown inFigureand was used for the elastic-plastic dynamic analysispreviously discussed.Thiscurve represents theresistance function of the structure.l-10 Y60 0.002FSARThe ductilityreferred to in the elastic-plasticdynamic analysis represents the ratio of the maximum displacementof the structure to the deflection established as yieldforthe structure.While it is recognized that the ductility ratio is not an exactmeasure of the maximum strain at a particular point of thestructure, it can be used as an approximation because theat yield in the actual structure is very nearly the straincorresponding to yield for the idealized structure.The procedure used herein is based on the peak of the actualforcing function resulting from the-aircraft impact, the durationof loading, theresistance function for the structureand the first natural period of the responding part of thestructure.By using the above known quantities, the correspondingductility ratio for the structure may be determined.For a peak in the forcing function of and ain the resistance function of 8,130 k, the maximum ductility ratiofor all ratios of is Fig. 2-26, Ref. 2).Thus, regardless of the natural period of the responding part ofthe structure, the largest displacement that will occur under theaircraft impact loading is the same as that to yieldfor the idealized structure.The yield strain for the reinforcing steel is SBFSARIf it is assumed that thecorresponding to yieldforthe idealized structure is 50% larger than this (actuallymuchless than this),, then an upper bound for the strain in thereinforcing steel will be:x 1.5 x 0.002 in/in =in/inSince the liner and the tension reinforcing steel are only severalinches apart in a 42" thick containment dome, they will bestrained to nearly the same values.Hence, there will be nopossibility of impairing the leak tight integrity of the liner.1.4 Response of the Enclosure Building During the early stages of the impact process, the enclosure buildingwill deform until it comes into contact with the containment. Theenclosure building must deflect five feet in order to come intocontact with the containment dome.Such a deformation will involvean inelastic response.This inelastic response will involve bothflexure and shear.The 15" thick enclosure building is reinforced withboth ways and both faces.The collapse load is 635k.The allowable shear load will depend upon the shear area over whichthe transverse shear stress acts. This shear area is determined bymultiplying the average shear periphery by the effective depth ofthe shell. The average shear periphery is determined by a contourwhich is at a distance of one-half the effective depth away from thecontour of the contact area (Figure 12 to 21 show theimpact area and shear periphery associated with various locations1-12 FSARalong the aircraft and for the effective depths of the enclosurebuilding (9") and containment (37").The reaction as a function of the cross section being crushed isdetermined from the reaction-time and crushing distance relationshipand is shown in Figure 22.From this information, it is possible to examine the effect of theaircraft impact on the enclosure building as a function of thedistance being crushed.Figure 23 shows the average shear stresson the enclosure as a function of distance being crushed.Forexample, using a shear strength of 4.25the enclosure buildingwill fail by shear when the aircraft is crushing at 7.25 feet.Alsoshown on Figure 23 is the reaction as a function of the distance beingcrushed.For a collapse load ofthe enclosure building willcollapse when the aircraft is crushing at 9.75 feet.It wouldappear that, usingas a shear strength,the enclosurewould fail by shear before collapse, however, the two eventswould occur at a time difference of 0.0086 sec. Any increase inactual shear strength abovewould increase the possibilityofand collapse happening simultaneously. Asbedomonstrated in Section 1.5, the actual shear strength can varyconsiderably above a value ofNo clear conclusion canbe drawn as to whether punch through or collapse occurs first. Basedon the above discussion, the failure of the enclosure building willinvolve both extensive shear and flexure damage and it will deformuntil it comes into contact with the containment.1-13 FSAR1.5 Shear Capability of the Containment The enclosure building will deform until it comes into contactthe containment dome.The dome will then resist the impact forceand experience transverse shear stress in the vicinity of the impactarea. The maximum average shear stress is determined by defining ashear perimeter and thickness over which the impact force is acting.Figure 24 describes the procedure by which the shear perimeter forthe maximum average shear stress acting on the containment dome isdetermined.The shear perimeter for the containment is at adistance(effective depth of enclosure) + ( effective depth of containment 2away from theof the impact area.The values of the shear perimeter for various cross sections of theaircraft are given in Table l-4.Also shown are the shear area,impact force and average shear stress for the containment building.The values of average shear stress as a function of the cross sectioncrushed is shown in Figure 25. The shear stress is given interms of psi andThe maximum value of the average shear stressoccurs when the aircraft is crushing at a distance of 35 feet fromthe nose. The value of this maximum average shear stress is 229 psiorVarious shear strengths have been proposed.A tabulation of theseshear strengths, for parameters similar to the aircraft and structureunder discussion is shown in Table l-5.It is seen that the maximumnominal shear stress ofis less than all the otherproposed values except the conservative value ofas proposed by the1-14 G1.01-15B2.570.454dmxeVWKFSARXI-Committee 326.Hence, it is concluded the the containmentwill not fail by punch through.1.6 Requirements to Prevent Perforation The velocity of the engines as they impact on the enclosure buildingand containment is 250 fps.The FB-111 has two Pratt Whitney(Military designationjet turbo fan engines with an outside diameter of 50.22inches.Each engine has a dry weight of 4,121 pounds (Ref. 1).The thickness of the dome required for no performation was determinedusing procedures reported in Reference 7.The pertinent nomenclature is :penetration thickness for infinitely thick slab (inches)perforation thickness for reinforced concrete (inches)diameter of missile (inches)velocity of impact (feet per second)weight of missile180ultimate compression strength of concrete (psi)
FSARSince a jet engine is not completely solid (thin shells for torquetransmission, blades for fan, compressor and turbine, burner cans forcombustion) the engine was assumed to behave similarly to a hollowpipe missile.For a fan-jet, the outside diameter is slightly larger than the gasgenerator.Two values of dm (the diameter of the gas generator)were used, SO.23 inches and 40 inches. The results are:dm (inches)21.822.8These values can be compared with the dome thickness of 42 inches.From these calculations,can be concluded that there will be noperforation.1.7 ConclusionsFrom the above results of the analysis of theStationContainment,the following conclusions can be made:1.The enclosure building will fail and will come into contact withthe containment building.The mode of failure will not be byshear or flexure alone, but will involve both types ofdamage.2.The containment building will not fail.Thestrength willprevent collapse.The shear strength will prevent.punchThere will be permanent damage to the structure, but the extentof this damage will not be sufficient to cause loss of theintegrity of the building.l-16 FSAR3.The linerinelastic, will be sufficiently smallso that tearing of the liner will not occur.4.The engines will not perforate the containment.These conclusions can be made even though the above analysis wasperformed with considerableThe conservative aspectsof the analysis are:1.The reaction-time relationship was determined for impact on a rigidtarget. A realistic, flexible target would reduce the peak valueof the reaction.2.Normal impact was assumed.Any impact angle other thanreducesthe impact forceand increase the area over which the impactforce acts.3. The arcing effect of the doubly-curved dome was ignored. Archingincreases the collapse and punching load capacities.4.The shear stresses can be computed more accurately using theeffective forceduring the time necessary for thestructure to respond rather than the peak instantaneous force.The peak instantaneous force will give larger shear stresses thanthe effective force.5.The actual concrete compression strength will be larger than thespecified strength of 3,000 psi.This would result in a largervalue for the shear strength.6. A conservative estimate of the shear periphery used to calculateshear areas and shear strengths wasThe1-17 FSARfailure cone was assumed to be through the containment only andnot through the combined thicknesses of the containment andenclosure building,The latter would be more accurate.The integrity of the containment buildingnot be impaired in theoccurrence of the postulated aircraft impact.
1.8 REFERENCES
FOR SECTION 1.01."FB-111 Unit Inertia Data, "General Dynamics, Fort Worth Division,Report FZS-12-6010, Revision "A", January, 1968.2.Riera, J.O., "On the Stress Analysis of Structures Subjected to AircraftImpact Forces" Nuclear Engineering and Design, North Holland PublishingCompany, Amsterdam, Holland, 8p. 415-426.3.Ghosh, S., and Wilson, E., "Dynamic Stress Analysis of AxisymmetricStructures Under Arbitrary Loading", University of California,Berkeley, CA., Revised Sept., 1975.4.Biggs, J. M., Introduction to Structural Dynamics, McGraw-Hill, Inc.,1964, pps. 69-84.5. Meiorovitch, Analytical Methods in Vibrations, The Macmillan Company,1967, p. 183.6.Save and Massonnet, Plastic Analysis and Design of Plates, Shells and Disks, North Holland, 1972, p. 245.7.Kennedy, Effects of an Aircraft Crash Into a Concrete Reactor ContainmentBuilding.HolmesNarver, Inc., July, 1966.1-18
-478-478FSARTABLE l-lMAXIMUM RESPONSEANALYSIS(IMPACT AT DOME)MeridionalCircumferential Element 36 is elementabove springline.FSARTABLE 1-2RESPONSEASYMMETRIC ANALYSIS(IMPACT AT SPRINGLINE)Meridional-1139Ft-K/FtCircumferential-1309Meridional383Circumferential442Meridional-1148.Ft-K/FtCircumferential1350Meridional*378Circumferential431Element 37 is element immediately below springline.
SectionTABLE l-3ALLOWABLEFORCE, MAXIM?? RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATING TARGET MATERIAL RADII31.121.2331.151.1231.201.3331.251.47Participating Radius; since this is notdefined, a range of values isincluded.** By observation, Pigure 2.26,"Introduction to StructuralRiggs-3( 1.00 x 10-29.03 x1.61 x 104.92 x 10-2T4.01 x 10-33.61 x 10-26.42 x 10-24a12162024322.51 xCracked Section41.24x137.1a4.92x10-334.2121.12x10-215.2161.99x10-2a.53-210203.11x105.43-210244.48x3.8310286.09x2.83-210327.96x102.131011.101.201.101.301.171.361.231.471.251.70170.042.418.810.6 1-4AVERAGE SHEAR STRESSLocationShear Perimeterft.ft.Shear AreaReactionpoundsAverage ShearStresspsi*If the wings were assumed to have sheared-off at the time that the aircraft were crushing at this locationthe shear perimeter and reaction would-be reduced to 64.6 ft. andrespectively. The average shearstress then becomes 198 psi.the horizontal and vertical stabilizers were assumed to have sheared-off at the time that the aircraftwere crushing at this location the shear perimeter and reaction would be reduced to 42.1 ft. andrespectively. The average shear stress then becomes 209 psi.average shear stress for the case were the crushing strength is reduced by 5 is 245 psi.32.614,47437.016,42841.818,55950.222,28899.844,31145.520,20249.221,84449.221,84415193541505889229178686,00032 Ultimate Shear StrengthpsiUltimate Shear Strength71765560752752552344539138336335129221913.111.911.089.629.589.557.146.996.626.415.334.00SBFSARTABLE l-5COMPARISON OF ULTIMATE SHEAR STRENGTH CAPACITY*equation 5-2,equation 5-1,=equation S-10,=equation 5-5,=equation 5-2,= 1equation 5-3,=equation 5-1,= 1equation S-10,= 1equation 5-5,1equationequationequation 5-6equation 5-9,326shear stress at distanced/2 from periphery = 1*"The Shear Strength of Reinforced Concrete Member-Slabs",JointTask Committee426, Journal of the Structural Division, ASCE, Aug., 1974.c = 93"= 3,000 psip = 0.0099d37"Y60,000 psi**Adjusted for circular region,evaluated at d/2 away from periphery.
10 FT 3 INI.133FT., II IN.STA270.50STATICGROUND LINESTA562.97 704020Figure 2B E I G H TSB 1 2FSAR73.5---FigureI I I60040 8622FSAR TIMESECONDSFIGURE 3REACTION-TIME RELATIONSHIP 5PFSARP denotes the scale crushing load used in the calculation.and5 denotes that one-fifth and five time the crushing loadused,'respectively.1086T I M ESECONDSFIGURE 4Reaction-Time Relationship for FB-111 with impact velocities of 200 mph.
SB 1 & 2FSARFIGURE 5FINITE ELDIENT MODEL FSARNO.3S T A T I O NFIGURE.6FOURIER SERIES REPRESENTATION OF SPRINGLINE LOADING 00.050.100 . 1 50.200.250.30FIGURE 7 ACTUAL AND IDEAL REACTION TIME RELATIONSHIP MATERIAL,FSARFIGURE 8ALLOWABLE MAXIMUM FORCE, MAXIMUM RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATION TARGET MATERIAL RADII SBFIGUREBEHAVIOR ANDLINE CONFIGURATION FSARFIGURE 10.LOAD-DISPLACEMENT CURVE FOR REINFORCED CONCRETE SB 1FSAR
- 15.2 ft.30.2 ft.Shear PerimeterSBFSARFigure 13, Impact Area and Shear Perimeter at 8.5 Feet From Nose SBShear PerimeterEnclosure17.8 ft.Containment31.8 ft.Figure 14, Impact Area and Shear Perimeter at 9.9 feet From Nose SBShear Perimeter- -ft.Containment 32.6 ft.FigureImpact Area and Shear Perimeter at 15 Feet From Nose FSAR\\IShear PerimeterContainment37.0 ft.Figure 16, Impact Area and Shear Perimeter at 19.0 Feet From Nose Shear PerimeterContainment37 ft.FSARFigure 17, Impact Area and Shear Perimeter at 27 Feet From Nose FigureImpact Area and Shear Perimeter at 35 Feet from NoseShear Perimeter'Containment 50.2 Ft.SBFSAR
...Containment - 99 8 ftShear Perimeterm.MIN********.*1.Figure 19, Impact Area and Shear Perimeter at 41.0 Feet From Nose Shear PerimeterContainmentII43.2 ft.SB2FSARFigure 20, Impact Area and Shear Perimeter at 50.0 Feet From Nose Shear PerimeterContainment 49.2 ft.Figure 21Impact Area and Shear Perimeter at 58.0 Feet From NoseFSAR IDISTANCEFEET1010304050602FIGURE 22, REACTION-CRUSHING LOCATION RELATIONSHIP JPSI6.005.0025010012345671750DISTANCE CRUSHED-FT.Figure 23 Average Shear Stress-Distance Crushed and Reaction Distance CrushedRelationship for the Enclosure Building.
2Effective Shear Area24 SCHEMATIC FORSHEAR 25STRESS-DISTANCE CRUSHED RELATIONSHIP FOR CONTAINMENTDISTANCE CRUSHED229 PSI FSAR2.0FIRE HAZARD ANALYSIS OFSTATION CONTAINMENTFOR AIRCRAFT IMPACTA highly unlikely chain of adverse events is postulated in thefollowing manner:An FB-111 with a weight of 81,800 lbs and initial speed of 200mph impacts on one of the two double containment complexes of thebrook plant.The enclosure building deforms locally under the initialimpact,and the local deformation continues with little to no perforationuntil the enclosure building comes into contact with the containmentbuilding.This fact, plus the fact that if any penetration should occurit would be only the nose of the aircraft, will preclude the spillingof significant amounts of fuel into thespace. Thespacecontains no equipment,and all penetrations both mechanical and electricalare isolated from missiles and fuel by reinforced concrete slabs,Theenclosure building acts as a barrier and directs the spilled fuel to theexterior area near the enclosure building.The following effects werethen studied:Possible production of combustible vapor, its promptignition and the ensuing pressure pulse, and thepossibility that the combustible vapor may be suckedinto the plant areas and be cause for delayed ignitionor toxic atmosphere in habitability systems.The fuel spilled and its transport to various areas ofthe plant. An ignition is then postulated, and theeffect of the ensuing fire studied in order to evaluate2-l FSARthe safe shutdown capability of the plant.The effect of smoke and/or toxic gases as may be generatedby the fire, with particular reference to control roomhabitability.The effects as detailed in (1) and (3) for all smaller air-craft.2.1COMBUSTIBLE VAPOR PRODUCTION The FB-111 carries approximately 32,000 lbs of type JP-4 fuel. Asindicated in Reference 1, the process of combustible vapor production isas follows:the crashing aircraft drags along the ground in a relativelyslow deceleration (0.4 g) which lasts for a 'long' time (20and thefuel issuing from the wing after some postulated leakage mechanism isatomized to mist by the air as a result of its velocity relative to air.For the direct impact considered here,the decelerations are very high(peak value of 29 g) and of very 'short' duration (0.3 sec.).The atom-izing process under these conditions is not significant.It is, there-fore, concluded that the combustible vapor production and the associatedhazards can be considered to be mitigated.2.2FIRE ANALYSISVarious spill mechanisms are postulated either on the roofs or onthe ground adjacent to the containment structure:The various roof areas adjacent to the containment enclosurewith their elevation approximate areas, etc., are detailedin Table 2-1.As stated in PSAR Section 2.4, most of theseroofs have parapets, and the roof drainage systems aredesigned to drain at least 3 inches per hour rain. It is2-2 FSARnoted further that 1 inch of fuel takes 10 minutes toUsing the minimum area in Table 2-1, and acatastrophic instantaneous mode of fuel release, themaximum expected duration of the fire is 17.9 minutes.For ground areas adjacent to the containment, there isapproximately 1.5 acres of land, the total drainage ofwhich is approximately 6 cfs.The spreading of the fuelover this area and the adequate drainage would result ina film fire with width comparable to the roughness of thepavement, e.g.,inch.The resulting fire would lastonly for 1 minute at the most.The mechanism of fire propagation was examined. No flamm-able material is normally expected to be present next tothe containment which can serve as the propagator of thefire. The range of the fire has very conservativelyestimated to be 200 ft. from its point of origin.Smoke is postulated to be traveling from this centre firelocation carried by the wind.Its effect on the habitabilitysystems was then studied.The possible hazard of fuel getting into the PAB Buildingthrough the vent stack is considered remote due to the follow-ing reasons:The mechanism is improbable.The entering fuel will be drained off at the base ofthe vertical stack, just as rainwater would be.The possible hazard of fuel getting into the main steam linetunnels through the side vent openingsconsidered notprobable since the vent openings are above grade.2-3 FSAR2.3 EVALUATION OF VARIOUS SAFETY RELATED AREASThe various intake points to the safety related areas and theirdescription8 are detailed in Table 2-2,including the missile shieldswhen applicable, under the accident conditions detailed in Subsection2.3. All buildings other than the control room and the PAB residualheat removal area are either not needed for safe shutdown or are redun-dant.However, the conservative analysis below includes the reactionof these areas to the postulated fire.(a) Control Room There is no mechanism for the fire to endanger the habitabilityof the control room, since the split intake vents are at adistance of at least 300 ft. from the containment; therefore,it is beyond the reach of the direct fire. However, in theremote event that the fire finds its way into the intakestructure, the temperature and smoke sensors will sense itthe intake opening will be closed. Under theseconditions, the other intake will be used for ventilating thecontrol rooms.Primary Auxiliary Building (PAB) The air intake is located on the east wall of the primaryauxiliary building at an elevation ofThe area infront of the intake has the containment enclosure roofelevation ofand the east wall of the PAB faces thecontainment and the fuel storage building.There may be afire lasting 12.5 minutes at most on the roof of thecontainment enclosure area, a part of which may be injectedinto theair intake, as its height is 3 ft. above the2-4 FSARroof of containment enclosure area.The inside of thePAB has roll-type filters after the intake and heatingcoil panels after the filter.Therefore,the flame andthe hot gases would have to penetrate the filter and thecoils before reaching the fans.As indicated in Subsection 2.2, the roof surface of thecontainment enclosure area will be finished smooth andwith proper drainage to drain off the spilled fuel quickly.Smoke and heat sensors will be located at the air inlet sothat on a signal from them the operator can stop the fans.Diesel Generator BuildingThe diesel generator building intakes are on opposite sidesof the building and are located at least 180 ft. from thecontainment structures.It is considered improbable thatthe spilled fuel will find its way underneath one of theseintakes.Furthermore,the intakes are 28.5' above gradelevel, and it is unlikely that the fire will rise to thatheight.In addition, one of the intakes is shielded bythe diesel generator building and it is thus not consideredcredible that the fire could reach that intake.Althoughit may be postulated that the hot gas from thepoint may cause momentary oxygen starvation ofgenerator, the shielded intake will ensure theother diesel generator and of one train.Service Water Building direct intakeone dieselintegrity ofThe intake for the service water building is approximately280 ft. from the containment'and should be out of reach ofthe postulated fire.Furthermore,the air intake is located2-5 FSARin the east wall of the building.Consequently, thebuilding serves as a shield for the spilled fuel flow.Additionally, there is a missile shield in front of thestructure, which should inhibit any possible fuel flowand subsequent fire.The fire effects are, therefore,considered minimal. However, a minute amount of hot gasmay enter the facility, but since the pumps are locatedat the west end of the building, it will not criticallythreaten their operation due to rise of temperature.Vent StackThe vent stack is not a safety related item and, as in-dicated in Subsection 2.2, it does not furnish a significantpathway for the fuel to get into the primary auxiliary build-ing. This mechanism of fire propagation is, therefore, con-sidered incredible.Cable Spreading, Battery Room, Switch Gear Room and Cable Tunnel The air intake for cable spreading, battery room, switch gearroom and cable tunnel areas is through the mechanical equip-ment room of the diesel generator building, and the varioussafety aspects discussed for the diesel generator room holdfor this case.2.4HAZARDS FROM SMALLER AIRCRAFTThe smaller plane crashes were examined for the various areas, asdetailed in Subsections 2.2 and 2.3. The fuel in general may be JP-1,kerosene and JP-4.Since the fuel carrying capacity for all these planesis smaller than that of FB-111, and their burning temperatures are of thesame order of magnitude, it was concluded that the effect would be envelopedby those in the case of FB-111.2-6 FSARCONCLUSIONS In view of the results in Subsectionsandit was con-cluded that the hazard toStation from direct fire after thepostulated crash of an FB-111 or smaller aircrafts on the containmentrepresents only very minimal potential hazard to the plant.The presentdesign of the plant has inherent safety features so that the consequenceof this minimal hazard is mitigated.REFERENCES FOR SECTION 21.Appraisal of Fire Effects From Aircraft Crash at Zion PowerReactor Facility, I. Irving Pinkel,Consultant, Atomic EnergyCommission, July 17, 1972.Flammability Characteristics of Combustible Gases and Vapors,Bulletin 627, U. S. Bureau of Mines, 1965, Michael Zabetakis.
BUILDINGSROOFAREA(SQ.FT.)ELEVATIONREMARKSCONTAINMENT ENCLOSURE4,10053'WITH PARAPETEMERGENCYFEEDWATERPUMPBLDG.3,00047'WITH PARAPETFUEL STORAGE BUILDING9,20084'WITH PARAPETPRIMARYAUXILIARYBUILDING8,14481'WITH PARAPETPAB Filter Room2,856108'WITH PARAPETTABLE 2-lROOF DESCRIPTIONSNOTE:GRADE ELEVATION 20' TABLEVENTILATION SYSTEM DESCRIPTIONS OF THE BUILDING SURROUNDING THE CONTAINMENT .,SHEET 1 OFBUILDINGBUILDINGSURFACEFACING THE CONT.LOCATIONS OF THEINTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMCONT.WALLELEVATIONDieselGen.South wallSouthWall200 ft.28.5ft.above gr.Other Bldg.at 40'dist..Ventilationair;notnecessaryforsafeshutdown.NorthWall240 ft.(thruroof)28.5 ft.aboveOther Bldg.at40PABEast wallEastWall20 ft.3aboveadjacentroof.Shielded bythe Cont.F.Stg.Bldg.Normalventilationair;only RHRpump area safeshutdownrelated.NorthWall95ft.(thruroof)29ft.above gr.thickshield.Ventilationairtosafety relatedmary component cool,ing water pump areaand Boron injectionpump area.EmergencyFeedwaterPump Bldg.South WallNorthWall30 ft.(thruroof)18ft.above gr.2'thickconcretemissileshieldVentilationairtothe emergencywater pump area.
TABLE 2-2 (CONT.)SHEET 1 OF 2BUILDINGBUILDINGSURFACEFACING THE CONT.LOCATION OFTHE INTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMELEVATIONCONT.WALLServiceWaterPumpHouseWest WallEastWall290ft.(throof)ru45 ft.above2'thickmissileshield.Ventilationairtotheservice waterpump house.WestWall180ft.13.5above2'thickmissileshield.Air intake to theelectricalareas.ControlRoomComputerRoomSouth 6EastWallsRemoteIntakePorts300ft.least)At gr.levelCoveredwithgrating.Ventilationairtothe habitable areasof the control andcomputer room.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-1 APPENDIX 2Q EAB AND LPZ SHORT TERM ACCIDENT DIFFUSION ESTIMATES FOR AST 2Q.1 OBJECTIVE Conservative values of atmospheric diffusion at the site boundary (EAB) and the low population zone (LPZ) were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2Q.2 METHODOLOGY The methodology used for this calculation is consistent with Regulatory Guide 1.145 as implemented by the PAVAN computer code (Reference 2). Using joint frequency distributions of wind direction and wind speed by atmospheric stability, the PAVAN computer code provides relative air concentration (CHI/Q) values as functions of direction for various time periods at the site boundary and LPZ. Three procedures for calculation of CHI/Qs are utilized for the site boundary and LPZ; a direction-dependent approach, a direction-independent approach, and an overall site CHI/Q approach. The CHI/Q calculations are based on the theory that material released to the atmosphere will be normally distributed (Gaussian) about the plume centerline. A straight-line trajectory is assumed between the point of release and all distances for which CHI/Q values are calculated. The theory and implementing equations employed by the PAVAN computer code are documented in Reference 2. 2Q.3 CALCULATIONS/PAVAN COMPUTER CODE INPUT DATA The boundary distance used in each of the 16 downwind directions from the site was set to 914 m. The LPZ boundary distance was set to 2,011 m. All of the releases were considered ground level releases because the highest possible release elevation is from the plant stack at 185 ft above plant grade. From Section 1.3.2 to Reference 1, a release is only considered a stack release if the release point is at a level higher than two and one-half times the height of adjacent solid structures. For the Seabrook plant, the elevation of the top of the containment is 199.25 ft. Therefore, the highest possible release point is not 2.5 times higher than the adjacent containment buildings, and thus all releases were considered ground level releases. As such, the release height was set equal to 10.0 meters as required by Table 3.1 of Reference 2. The building area used for the building wake term was 2,416 m2.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-2 The tower height at which the wind speeds were measured is 10.05 m above plant grade. The windspeed units are given in miles per hour, therefore the PAVAN variable UCOR was set equal to 101 to convert the windspeeds to meters per second as described in Table 3.1 of Reference 2. The maximum windspeed in each windspeed category was chosen to match the raw joint frequency distribution data, which conforms to the windspeed bins in Table 1 of Reference 3. 2Q.4 RESULTS PAVAN computer runs for the EAB and LPZ boundary distances were performed using the data discussed previously. Per Section 4 of Reference 1, the maximum CHI/Q for each distance was determined and compared to the 5% overall site value for the boundary under consideration. For dose calculations, the most limiting 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> CHI/Qs were combined with the worst 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> EAB doses to maximize calculated EAB doses (conservative approach). The maximum EAB and LPZ CHI/Qs that resulted from this comparison are provided in the table below: Offsite Boundary /Q Factors for Analysis EventsTime Period EAB /Q (sec/m3)LPZ /Q (sec/m3) 0-2 hours 3.17E-041.54E-04 0-8 hours 2.08E-048.63E-05 8-24 hours 1.68E-046.46E-05 1-4 days 1.06E-043.45E-05 4-30 days 5.51E-051.40E-05 2Q.5 REFERENCES 1. USNRC Regulatory Guide 1.145, "Atmospheric Dispersion Models for Potential Accident Consequence Assessments at Nuclear Power Plants," Revision 1, November 1982, (Reissued February 1983 to correct page 1.145-7). 2. NUREG/CR-2858, "PAVAN: An Atmospheric Dispersion Program for Evaluating Design Basis Accidental Releases of Radioactive Materials from Nuclear Power Stations," November 1982. 3. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-1 APPENDIX 2R SHORT-TERM (ACCIDENT) DIFFUSION FOR THE CONTROL ROOM 2R.1 OBJECTIVE Conservative values of atmospheric diffusion to the Control Room were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2R.2 METHODOLOGY The ARCON96 computer code is used by the USNRC staff to review licensee submittals relating to control room habitability (Reference 1). Therefore, the ARCON96 computer code was used to determine the relative concentrations (CHI/Qs) for the control room air intakes and inleakage locations. The ARCON96 computer code uses hourly meteorological data for estimating dispersion in the vicinity of buildings to calculate relative concentrations at control room air intakes that would be exceeded no more than five percent of the time. These concentrations are calculated for averaging periods ranging from one hour to 30 days in duration. The theory and implementing equations employed by the ARCON96 computer code are documented in Reference 1. 2R.3 CALCULATIONS/ARCON COMPUTER CODE INPUT DATA Five years of meteorological data (1998-2002) were used for the ARCON96 computer code runs. The percentage of valid data over this time period was 98.8% which exceeds the minimum value of 90% data recovery specified in Reference 2. A number of various release-receptor combinations were considered for the control room CHI/Qs. These different cases were considered to determine the limiting release-receptor combinations for the various events. The case matrix for these combinations is provided in Table 2R-2. The distance and direction inputs for the ARCON96 runs may be found in Table 2R-1. The distances were converted from feet to meters with a factor of 0.3048 m/ft. The distances in meters were then rounded down to the nearest tenth for conservatism. The elevation difference term was set equal to zero for each case since all elevation points are taken with respect to the same datum.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-2 The lower and upper measurement heights for the meteorological data were entered as 10.05 m and 60.66 m, respectively, for each case. The mph option was selected for the windspeed units. A ground level release was chosen for each scenario since none of the release points are 2.5 times taller than the closest solid structure as called out in Section 3.2.2 of Reference 3 for stack releases. The top of the containment structure is at an elevation of 199.25 ft. The highest release point is from the top of the plant stack at an elevation of 185 ft., which is not 2.5 times higher than the nearby containment structure. The vertical velocity, stack flow, and stack radius terms were all set equal to zero since each case is a ground level release. The vent release option was not selected for any of the scenarios. The actual release height was used in the cases. No credit was taken for effective release height due to plume rise; therefore, for the releases from the stacks, the release elevations were set equal to the stack top elevation. The release heights were taken as the release elevations less the plant grade elevation of 19 ft. The only cases in this analysis that take credit for the building wake effect are the scenarios where the release is from the containment building, the tank farm, or the waste processing building. Some of the other scenarios have buildings between the release and receptor points, but for these cases the building wake was not credited for the sake of conservatism. Not crediting wakes was accomplished by setting the building area term equal to 0.01 m2 as stated in Table A-2 of Reference 3. The first building area used is a conservatively determined containment cross sectional area. The area is calculated as the sum of the cross sectional areas created by the cylindrical portion of the containment structure above the highest nearby roof and the hemispherical area of the dome. The width used is equal to the diameter of the containment structure. The height of the cylindrical portion is taken as the distance between the top of the cylinder portion of the containment structure (represented by the spring line elevation) and the primary auxiliary building roof elevation. The radius of the hemispherical dome is taken as one half of the calculated diameter. The containment area was determined to be 1,506 m2. The second building area is calculated as the product of the minimum roof height of the waste processing building and tank farm and one half the width of the waste processing building and tank farm. The minimum roof height and one half of the width are used for conservatism. This building area was determined to be 337 m2. All of the default values in the ARCON96 code were unchanged from the code default values with the following exceptions. Table A-2 of Reference 3 suggests use of a value of 0.2 for the Surface Roughness Length, and use of a value of 4.3 for the Averaging Sector Width Constant. These two changes were made for each case. The minimum wind speed was left at 0.5 m/s per the guidance instruction in Table A-2 of Reference 3.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-3 2R.4 RESULTS ARCON96 computer runs for the various release points and control room intake locations were performed using the data discussed previously. Per Reference 3, the 95th percentile CHI/Q values were determined. The resulting CHI/Qs are listed in Table 2R-2. 2R.5 REFERENCES 1. NUREG/CR-6331 PNL-10521, "Atmospheric Relative Concentrations in Building Wakes," May 1995, with Errata dated July 1997. 2. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. 3. USNRC Regulatory Guide 1.194, "Atmospheric Relative Concentrations for Control Room Radiological Habitability Assessments at Nuclear Power Plants," June 2003.
UPDATED FSARAPPENDIX 2LGEOLOGIC INVESTIGATION OF SOILS AND THE BEDROCK SURFACE ATUNIT 2 CONTAINMENT SITE.STATIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
GEOLOGIC INVESTIGATIONSofSOILS AND THE BEDROCK SURFACEat2SITESTATIONPUBLIC SERVICE COMPANY OF NEW HAMPSHIRENEW HAMPSHIREOctober 24, 1974 CONTENTS1.Purpose of I nvc stigations2.Borings Investigationsto Boring3.Trench Excavations4.Bedrock* Exposed in TrenchesA.FaultingB.Jointing5.Unconsolidated Glacial Deposits6.ConclusionsFigure 1Public Service Company of NewSite SurveyFigure 2Geologic Map Unit 2 TrenchesFigure 3Soils ProfilesUnit 2 TrenchesAppendix IBoring Log BoringAppendix IIGeotechnical Report, Reactor BoringsGeotechnical Engineers, Inc.Page12334456 GeologicalofSoils and the Bedrock SurfaceUnit 2 Containment SiteStationNew HampshireAugust and early September, 1974, four trenchesin length were excavated to bedrock on anconfiguration acrossthe area of the Unit 2 containment site at theStation,Hampshire.The bedrock in the floor of these trenches is gneissoid quartzdiorite of the pluton, which is commonly fractured atthan 3* intervals in this area by an intersecting pattern ofangle and low-angle joints. The most prominent and continuous jointse; within the containment area appears to b one which strikesdips steeply to the north, and is by smoothcoated joint surfaces.Unconsolidated overburden in the area ranges to amaximum of 16* in thickness, and is characterized by adeposit of sand-silt-cobble till locally overlain by a blanket offine sand. Glacial-marine clay lies between the till andwash to the east of the containment. covered by sand,the upper surface of the till is beveled to a gently undulating,planar erosion surface upon which rest isolated boulders rangingtoin diameter.No evidence of Recent fault displacement was observed on thesurface in the Unit 2 trenches. The sub-planarcontact horizon, which occurs in three of the four trenches, shows noevidence in these areas of static or dynamic deformation.1. Purpose of Investigations Bedrock at the site of the proposed Unit containment is largelyobscured by glacial till, glacial-marine clay andsand. Bor-ingdrilled in December 1972 to a depth of 159.2* on the verticalcenterline of Unit 2, encountered thinof structural weakness inthe diorite bedrock at intervals between elevations -75* and These zones are characterized bychlorite-richhigh-angleandclosely jointed zones in chlorite-richof the bedrock. High-angle joints indip fromtoand most commonly dipTrenching investigations over the Unit 2 site werein1974 for precautionaryto ascertain theof thedeposits in the urea and to examine the natureof jointing in the underlying bedrock surface.2.Investigations Subsequent to BoringDuring April 1974, Eoringwas drilled to a depth of 97.8*at a iocatior, 33*(True) of the centerline of2 (see Appen-dix I for boring log) . This boring encounteredwith minorchlorite coatings a variouswith a zone of smoothcoated joints-64 to -79* elevations. These joints diptoand frequently show pyrite crystal growths over the chloritesurfaces.During 1974, four inclined borings,and 18, were down around the periphery of the Unit 2containment site to develop information relative to engineering of thecontainment Logs and orientation data for these boringsare presented in a July 31, 1974 report prepared byEngineers, Inc., Winchester, Massachusetts (see II) .Boringsandalong the west and south edges ofthe containment, respectively, encountered very few chlorite-coatedjoints.polished joint atdepth inappears likely to re-present the projection to depth of a prominent chlorite-coatedangle joint which is observed on the bedrock surface to trendthrough the centerline of Unit 2. There are no anomalouslypolished joints in BoringBoringdrilled northerly across the east edge of the con-tainment site, encountered polished chlorite-coated joints intermittentlyat depths of137* and 152-156*. Some ofthese joints appear tothe prominent east-west jointwhich trends through the centerline of Unit 2. This prominent jointappears to split into a number of high-angle branches as it passeseast into the zone of influence of Boring
,and(see Figure 1) .encounteredindividual jointshavecoatings.anomalously polished orrichfound,in thedepth drilled.injoint mapping of the bed-rock surfaceBoringsanddo not indicate the presence of a through-going faultinthe area of Unit 2. These borings do appear,tothat the most prominent orchlorite-coatedjoint system in thearea trends(True) through the central part of theand dipsto the north.3. Trench ExcavationsDuring August 1974, four trenches were excavated with a back-hoe to bedrock across the 'Unit 2 site, to form anwhose legs areeach203' long and intersect at right angles at thevertical centerline of the Unit. The legs trend approximately TrueNorth,Ground surfacein the area oftrenches range fromaboutto. The elevation of the bedrock surface in the floorof the trenches rangesabout -3'Stationin the East trenchtoat Stationin the South trench. Profiles of the bedrockface along the centerlines of the trenches, as surveyed by Public ServiceCompany 'of Newpersonnel, are shown on Figuresand 3.4.Exposed in the TrenchesFigure 2 shows by half-tonethe areas of bedrock mappedby J. R. Rand in the several trenches. Although the trenches wereto bedrock, throughout, the bedrock in theelevation areastoo obscured byand mud to permit the observation of jointsor other pertinentfeatures. Although much of the bedrocksurface is rough and irregular due to glacial plucking or breaking bythe backhoe, wide areas of the bedrock are locally smooth and showglacial striations.Throughout the area exposed by the trenches the bedrock con-sists predominantly of gneissoid, sometimes quartzitic, quartz dioritewhich ranges in grain size from fine- to orientations:StrikeDipStrikeDipStrikeDipNoofof'bedrock surface or the overlyingglacialin thebreccia fab-ric,isin drill corein the Unit 2 area andthroughout thearea, can beon a smooth5'ofi nThis breccia isdips steeply, is annealedcompact,andof the glaciated bedrock surface.B. Jointingon Figure 2, jointing in the bedrock is closely spaced2 containment area,a:andat less than 3'joints (greater thandips) occur in three prominentAt the centerline of Unit 2, the most continuoustrend is This set is seen----tohavechlorite-coated surfaces. __Thejointstos e t ,thejoints arestriations whichdirections ofLow-angle joints (less thanclips) appear to be somewhat morethan high-angle joints, and occurinprominentorientations:to t'ne north.characteristic&v short__lent.StrikeStrikeStrikeand SENE andand terminate against theoccur onof p l a n a r,showstriations, with no consistent striation orientationfrom joint to joint.Fromtoin the East trench, the bedrockis subject to closely-spaced jointing, and theof the bed-rocksufficiently fractured toexcavation by t'ne backhoe.Joints in this areand smooth, and show somepolishing on conchoidal surfaces. Thin gray clay fillings occur lo-cally in discontinuous patchessome joints.showno preferredand no strike direction could be determinedfor this zone.5. Unconsolidated Glacial Deposits As shown on trench profiles on Figure 3,cobble till directly overlies the bedrock surface throughout the areaexposed by the four trenches. Tillto ground surface through-out the length of the South trench, and rises locally to ground sur-face in the North trench and in the area of the Unit 2 centerline.the till does not rise to ground surface in the trenches, theupper surface of theis a gently undulating, sub-planar erosionsurface on which a layer of medium-fine sand.At the east end of the East trench, a sequence of interbedded,layered marine clays and sands lies between the and the over-lyingsand iayer. At scattered intervals in the West, Northand East trenches, isolated boulders ranging toin diameter lieenclosed insand and rest on the upper surface of the till.Subsequent to backhoe excavation of the trenches, the contacthorizon between the till and overlyingsand was exposed andcleaned by hand throughout the length of its exposure in the West,North and East trenches. The contact was inspected and photographedby J.Rand throughout its exposed length in these trenches, andits elevation determined by transit leveling along bothof each ofthese trenches. The extent of thesand deposits in the trenchand the elevations of thecontact from place to placeare shown on Figure 2.featuresobservedthiscontact in anyof the trenches to suggest either static or dynamic deformation sub-sequent to deposition of the sand on the beveled till surface. Through-out the zone of close and slippery bedrock jointing between Stationsandin the East trench, the overlyinghorizonis sub-planar and continuous.
Glacioverlying the bedrock surfacetheSouth trcrich are limited to unsorted, non-layered sand-silt-cobbletill.locallya crude stratification, and nowhereexhibit structures suggestive of podeformation.6.Examination of the overburden, bedrock surface and bedrockjoints in the Unit 2 trench excavations has revealed several distinc-tive featuresare indicative of the tectonic stability of the bed-rock at the site:A.Intermittentratified horizons in the glacial tillare not displaced over joints in the underlying bedrock.B.The undulating, sub-planar erosion surface at the top ofthe till is through-going and not subject to structural offsets or otherdeformations suggestive of faulting,C.Local exposures of glacially-scoured bedrock surfaces aresmooth across joints in the bedrock.D.Slickenside striations on closely-spaced bedrock joints ex-hibit widely divergent orientations, with no preferred attitude ororientation.John R. RandConsulting Geologist FIGURES
,o7BOULDERS ON TILL SURFACEOUTiASH AND BEACH SANDE SAND.SIL1.C2EBLE TILLLT: BENCIC IN TRENCH FLOCRSURVEYED ELEV. -.3,ASE CF SANTOP OF TREHCHBATE oF TAENT8 SL),**'\letak*,5e:frock ccpbisis prederninactlyof pissoid Newburgort Vetdiorite, fine- to mediurr.graine(locally ccarse hornblende \diorite, No diabase dikes WMnoted in the trench floor.PAC URVICE COUNAY Cr KW HAIPPIli&AIWA 51A10GEOLOGIC MAP UNIT 2 TRENCHESI Ow CoduiMIMI 10 UPDATED FSARAPPENDIX 2MGEOTECHNICAL REPORTPRELIMINARY REPORT. COMPRESSION TESTS ON STRUCTURAL BACKFILL AND SAND CEMENT,STATIONThe information contained in this appendix was not revised, but has beenextracted from the originaland is provided for historical information.
PRELIMINARY REPORT'COMPRESSION TESTS ONSTRUCTURAL BACKFILL AND SAND-CEMENTSTATIONJanuary 24, 1978Prepared forPUBLIC SERVICE CO. OF NEW HAMPSHIREandUNITED ENGINEERS AND CONSTRUCTORS, INC.Geotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890Project 77386 1.INTRODUCTION1.1 Purpose1.2 Scope1.3 ScheduleTABLE OF CONTENTSLIST OF TABLESLIST OF FIGURES2.DESCRIPTION OF STRUCTURAL BACKFILL ANDRESULTS OF INDEX TESTS2.1 Description2.2 Grain-Size Distribution Tests2.2.1 Procedure2.2.2 Results2.3 Specific Gravity Test2.3.1 Procedure.2.3.2 Results3.MOISTURE-DENSITY RELATION TEST4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTS4.1 Procedure4.2 Stress-Strain Curves For S Tests4.3 Moduli and Poisson's Ratios For S Tests5.1 Procedure5.2 Stress-Strain Curves ForTests5.3 Moduli and Poisson's Ratio ForTests6.TESTS ON SAND-CEMENT7.COEFFICIENT OFREACTION7.1 Structural BackfillNOTATIONSTABLESFIGURESAPPENDIX ASTRESS-STRAIN CURVES FOR DRAINED TESTSAPPENDIX BSTRESS-STRAIN CURVES FOR UNDRAINED TESTSPage No.243.1 Procedure3.2 Results5. CONSOLIDATED-UNDRAINED,TRIAXIAL TESTS910101344 LIST OF TABLESTable 1Schedule of Tests on Sand-CementTable 2Consolidated-DrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 3Consolidated-UndrainedTriaxial TestsStructural BackfillBeard Pit 5 SandTable 4Unconfined Tests on 2-in. Cube Samplesof Sand-Cement, 5% Cement .TableCompression Tests on 2.8-in.-diameterSamples of Sand-Cement, 5% Cement.*To be added when tests are complete. 2. DESCRIPTION OF STRUCTURAL BACKFILLAND RESULTS OF INDEX TESTS2.1 Description Beard Pit No. 5 soil is a yellowish-browngravelly sand containing about two percent fines.2.2 Grain-Size Distribution Tests Two sieve analyses were performed.The grain-size dis-tribution of Beard Pit No. 5 soil as received was first, determined. The entire sample wassieved on aNO. 4 (4.75 mm) mesh and a grain-size distribution of soilpassing the No. 4 mesh was determined.The minus No. 4 mat-erial was used for triaxial testing.2.2.1 ProcedureTo determine the grain-size distribution ofthe original soil, a representative samplewas selected, weighed and air-dried.Thesample was sieved on a mesh and ag-gregates retained were removed, weighed andseparately sieved. A representative sampleof aggregates passing the mesh wasweighed, oven-dried and washed on a No. 200mm) sieve.The soil retained on theNo. 200 sieve was oven-dried, weighed andmechanically sieved.The entire quantity of soil was then sievedon a No. 4 (4.75 mm) mesh and aggregates re-tained were removed. A representative sampleof soil passing the No. 4 mesh was oven-driedand washed on a No. 200mm) sieve.Soilretained on the No. 200 sieve was subsequentlyoven-dried, weighed and mechanically sieved todetermine the grain-size distribution of thesoil to be used for compaction and triaxialtesting.2.2.2 ResultsThe grain-size distribution curve of BeardPit No. 5 soil is presented in Fig. 1.The grain-size distribution curve of the soilpassing the No. 4 (4.75 mm) sieve is presentedin Fig. 2. 4.CONSOLIDATED-DRAINED, S, TRIAXIAL TESTSSix S tests were performed on compacted specimens ofBeard Pit No. 5 soil.Only soil passing a No. 4 sieve wasused.Specimens were compacted to 90% and 95% of the maxi-mum dry unit weight as determined by ASTM Designation D1557,Method A (Section 3).Tests were performed at effectiveconsolidation pressures of 0.5, 2.0 and 6.0 ksc (7.1, 28.4,85.3 psi).Test specimens typically had a diameter ofand a height of 6.6-in.4.1 ProcedureA predetermined quantity of air-dried soil was thoroughlymixed with distilled water to a water content of 14%.Themixture was divided in seven portions of equal weight andplaced in covered containers.The compaction was performed in seven layers within asplit mold. The mold was lined with a rubber membrane whichwas held tightly to the inside of the mold by a small vacuum.The first soil layer was placed in the mold and leveled off.A l-psi surcharge was lowered onto the soil and vibratedvertically using an Ingersoll-Rand pneumatic hammer.Thehammer provided low frequency-high amplitude vibrations.Thelayer was compacted to a predetermined height to achieve thedesired unit weight.The surcharge was removed and the soilsurface scarified. Subsequent layers were added and compactedin the same manner to form a test specimen of the desired sizeand unit weight.The mold and specimen assembly was then mounted on thebottom platen of a triaxial cell. A vacuum of approximatelyof Hg was applied to the specimen to provide support tothe specimen. The mold was removed and the diameter and heightof the specimen were measured. A second membrane was placedaround the specimen and O-rings attached to seal the membranesto the top and bottom platens.The triaxial cell was subsequently assembled and floodedwith water. A chamber pressure of 0.5 ksc was applied and thevacuum released to distilled water at atmospheric pressure.When the vacuum had dissipated, distilled water was permeatedthrough the specimen to improve saturation by displacing airvoids. A back pressure of approximately 10 ksc was utilized tocomplete saturation.B-values of 0.90 or higher were measured.
..a.normalized shear stress on theplane,vs. axial strain, andThe specimen was then consolidated to the desired effectiveconsolidation pressure. Volume changes during consolidationwere measured by monitoring the flow of pore water throughthe drainage system.The test specimen was subsequently loaded axially at aconstant rate of strain of approximatelyDuringshear the specimen was allowed to drain through both ends.Volume changes were measured by monitoring the flow of porewater. Axial loads were measured with a proving ring anddeformations were monitored with an axial dial.The testwas terminated at 20% axial strain.The specimen was thenremoved and oven-dried to determine the weight of solids.4.2 Stress-Strain Curves For S Tests Results of the consolidated-drained triaxial, S, testsare plotted in terms ofb. volumetric strain,VS. axial strain.The results of individual S tests are presented in Appen-dix A and Table 2 contains the details of each S test performed.A summary of S tests performed on specimens initially com-pacted to a specific 90% compaction are plotted in Fig. 4, and95% compaction in Fig. 5.4.3and Poisson's Ratios For S TestsFigs. 6 and 7 are plots of secant modulus and Poisson'sratio, respectively, as a function of axial strain from thetriaxial S tests.Fig. 8 (top) is a plot of the initial tangent modulus andthe secant modulus at 50 of the compressive strength versusthe effective consolidation pressure,At the bottom inFig. 8 is a similar plot for the values of Poisson's ratios. 6. TESTS ON SAND-CEMENTWe herewith forward results of tests on 2-in. cubespecimens of sand-cement, so that thewill be avail-able early in this preliminary form.In Fig. 13 are plotted the stress-strain curves for un-confined tests on three replicate specimens cured for 7 days,and in Fig. 14 are the stress-strain curves for unconfinedtests on three replicate specimens cured for 28 days. De-tails of these tests are given in Table 4.The sand-cement specimens were prepared using the samesand and cement that were used at thesite for testbatches.The mixtures are shown in Figs. 13'and 14.It may be seen that the strength increased rapidly withcure time. A strength increase that is logarithmic with timewould lead to the predition of an average strength of 180psi for the specimens curedmodulus would increase to 33,800 psi.Similarly, the average
- 7. COEFFICIENT OFREACTION7.1 Structural BackfillTo determine reasonable values for the coefficient ofreaction of buried pipes, the following proceduremay be used:1.Determine whether the loading condition is"drained" or "undrained." That is, will volumechanges take place during loading (drained), orwill volume changes not occur during loading(undrained) .2.Establish the allowable diametral strain ofthe pipe. That is, select a diameter-strainthat the pipe can withstand with an adequatefactor of safety. That strain may be as lowas 0.1% for stiff, brittle pipes,to 3% or 4%for flexible pipes.3.Compute the vertical effective stress in theground at the level of the middle (springline)of the pipe.4.Choose whether the expected degree of compactionof the structural backfill is 90% Modified or95% Modified.5.Given the above data, enter the appropriatetable below, and interpolate to obtain a valueofi.e., the coefficient oftimes the pipe diameter (in psi).6.Divideby the pipe diameter to obtain thevalue ofin pci (pounds/cubic inch).
TABLE 2CONSOLIDATED-DRAINEDTRIAKIAL TESTSSTRUCTURAL BACKFILLBEARD PIT 5 SANDSTATIONPercent Compaction, PEffectiveBAt Max. Compressive StressModuli ASTM D1557, AConsoli-ValueDeviator AxialVolumeInitial At 50%InIn Triaxial CelldationStressStrain StrainCompac-InitialAftertionConsoli-MolddationMax.Stress0Stresspcf--13.8100.7s213.8100.9s313.8101.0s413.8106.413.5106.3S613.7106.3GeotechnicalEngineersInc.Project 7738623, 1978pcfksckscpsip si100.8100.889.990.090.00.500.971.641.310.416,2604,0500.310.43101.0101.590.190.290.62.000.955.882.380.0814,22011,0900.170.23101.3102.390.290.491.46.000.9515.057.28-0.6623,75018,7700.220.23106.4106.495.095.095.00.500.952.341.310.9213,5109, 6000.330.35106.4106.894.995.095.32.000.977.960.9221,33016,1400.170.27106.4107.394.995.095.86.000.9519.354.000.3429,15024,7400.200.27Test InitialDry Unit WeightsNo.WaterInIn Triaxial CellContentInitialAfterConsoli-MolddationPoisson's RatioInitial At 50%Stress3ca STATIONSTRUCTURAL BACKFILLBEARD PIT 5 SANDEffectiveASTMA Consoli-Value Deviator AxialEffectiveInitialAt 50%InIn Triaxial CelldationMinorCompac- InitialStressPrincipaltionConsoli-StressMolddationTest InitialDry Unit WeightsPercent Compaction, P13.7101.0101.2101.290.290.490.40.500.966.869.532.635,8303,13013.5100.6100.6100.989.889.890.12.000.907.948.333.1112,7305,760ii313.8100.8101.1102.290.090.391.26.000.9911.326.69.4.4638,11018,63013.6101.0101.2102.390.290.491.36.000.9512.245.734.7724.46019,05013.8106.3106.5106.594.995.195.10.500.9519.9113.837.2311,8707,180ii513.6106.3106.3106.694.994.995.22.000.9521.8714.537.9319,7708,39013.5106.3106.4107.294.995.095.76.000.9627.8811.58io.3544,01014,220GeotechnicalEngineersInc.Project77386January 23,1978p pcf cfpcf- ksc -ksckscpsiCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSNo.WaterInIn Triaxial CellContent Compac- Initial AfterConsoli-MolddationBAt Maximum Compressive UnitWeightWetUnconfinedStrengthpsiStrainModulusAtofPeakElasticity*psiCureTimedaysTestNo.TABLE 4UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5% CEMENTSTATION77-1124.066.70.8010,600123.972.50.9210,110126.285.30.8313,650Avg 74.82828-1127.4141.60.67126.2133.80.77126.8130.00.87Avg 135.0Avg 11,45033,33019,13022,760Avg 25,0709090-290-3*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386.January 23, 1978 FIGURES Lab. 4-3 rev. 0U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER50050IOI0.5GRAIN SIZE MILLIMETERSCOBBLESSANDCOARSEFINECOARSEMEDIUMIFINEIIGRAIN-SIZEDISTRIBUTIONTriaxialTestsBEARD PIT NO. 5SOILStructuralBackfillProject77386Jan.23,1978Fig.1New HampshirePublic Service Company ofEngineers Inc.Winchester,Massachusetts Lab. 4 - 3 rev. 028 May 74500100505I0.50.10.05GRAIN SIZE MILLIMETERSISILT OR CL AYCOARSEFINECOARSEMEDIUMIProject 77306Jan. 23, 1978Fig. 2II\-10go-20I-IIIIIIIIIIIIIIIIIJ - 7 0809020IO0IIIIIU.S. STANDARO SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETER64 3I1420 30 40 50 70200II*IIIIIIIIIIIIIII\IIIIIIITriaxial TestsStructuralBackfillGRAIN-SIZE DISTRIBUTIONBEARD PIT NO. 5 SANDNO. 4 MATERIALPublic Service Company ofNew HampshireGeotechnical Engineers Inc. .Winchester, Massachusetts WATER CONTENT,As mixed before compaction0 After compaction1051 1 31 1 11 0 91 0 704122 024TESTSSTRUCTURAL BACKFILLMOISTUREDENSITYRELATION TESTBEARD PIT No.5 SOILJanuary1978 Fig. 3PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386ENGINEERS INC.WINCHESTER,MASSACHUSETTS PROJECT 77366DECEMBER, 1977 FIG. 43024681416182006.0AXIAL STRAIN, %ENGINEERS INC.VI NCH ESTER, M ASSACHUS ETTS 2.51.5.1.0TESTs40.5s52.0S66.006420-2024681416 1820AXIAL STRAIN,%TRIAXIAL TESTSSERVICE COMPANYOF NEW HAM SSV IR^EUC T U R A L B A C K F I L LDECEMBER, 1977 FIG. 5PROJECT 77386ISUMMARY OFDRAINED TRIAXIAL TESTSCOMPACTIONENGINEERS INC AXIAL STRAIN,F O RW0III30,0002 5,00020,00090% Modified Compaction10,000.IIIII00.40.60.81.01.21.42.0IIIW000.40.60.81.21.41.61.82.0IIIII95Compact ionIPUBLIC SERVICE gCOMPANYOF NEW TARPUSHfI2RET U R ENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386JANUARYTESTSA LB A C K F I L LDRAINED LOADING 1.61.82.000.20.40.60.81.01.21.4AXIAL STRAIN,TESTS90% Modified Compaction7.1psi0.20.40.60.81.01.21.41.62.0III95% Modified Compactionpsi .PUBLIC SERVICE COMPANYOF NEW HAMPSHIREPROJECT 77386JANUARYFig. 7,ENGINEERS INC.MASSACHUSETTS1.21 .o0.80.60.40.201.2.o0.80.60.40.20STRUCTURAL BACKFILLPOISSONS RATIOSFOR DRAINED LOADING 10020300E moduluscompactionEmodulus50%peakcompactionE modulus95% compactionE modulus atpeokcompaction95% compactionvat 50%peak95%90% compactionat 5 00.50.40.30.20.10kg(Multiply by 14.22 for psi)SERVICE COMPANYqF NEI HAMPSHIRECENGINEERS INC.YINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSUMMARY OFFSTRUCTURALILLDRAINEDTESTSPROJECT 77386FIG. 8 4678910TEST NO.0.502.0002468141618206.006.00AXIAL STRAIN , %SERVICE COMPANYSUMMARY OFTRIAXIAL TESTSOF NEW H'WWHIJRCET UR A LB A C K F I L LUNDRAINED TRIAXIAL TESTS90% COMPACTIONENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. 9 TEST NO.*3c kg/cm2kg/cm2R40.50R52.00R66.0006421214R6STRESS-STRAINR63024681012141618 20AXIAL STRAIN,%PUBLIC SERVICE COMPANYOF NEW HAMPSHIREGEOTECHNICAL ENGINEERS INC.WINCHESTER, MASSACHUSETTSTRIAXIAL TESTSSTRUCTURAL BACK FILLPROJECT 77386SUMMARY OF CONSOLIDATED-UNDRAINED TRIAXIAL TESTS95% COMPACTIONDECEMBER,1977 FIG. 10 SECANT MODULUS,psiundrained loadingSECANT MODULUS, Es, , psiundrained loading0DXriI I.II ENGINEERS INC.*WINCHESTER, MASSACHUSETTSPROJECT 77386DECEM 8FIG.(Multiply by 14.22 for psi)00 90% Compact ion90% CompactionCompaction 95% CompactionNOTE POISSONS RATIO FOR UNDRAINEDTESTS MAY BE TAKEN AS 0.49 TO 0.50
,12080400I2345AXIAL STRAINSand-Cement Mixture (by weight):1 part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimens7 daysUnit weight after cure7-1 124.07-2 123.97-3 126.2Strain control. loading at 1.5 mm/minPublicCompanyof New HampshireEngineers Inc.Winchester,MassachusettsCOMPRESSION TESTS7-DAY CURE5% CEMENTJanuary 1978Fig. 13Triaxial TestsStationSand-CementBackfillProject 77386
.,AXIAL STRAINSand-Cement Mixture (by weight):1part cement16.18 parts sand (oven-dry)2.79 parts waterPrepared as per ASTMSpecimens Tested:2 in. cube specimensCured 28 daysUnit weight after cure28-1 127.428-2 126.228-3 126.8Strain control loading at 1.5Public Service Companyof New HampshireTriaxial TestsCOMPRESSION TESTSSand-CementBackfill28-DAY CURBStation5% CEMENTGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386January 1978Fig. 14..
APPENDIX A SERVICE COMPANYPROJECT 77386ENGINEERS INC.10121618201.0VOLUMESTRESS STRAINAXIAL STRAIN,%TEST90% CompactionTRIAXIAL TESTSITRAL BACK F I L LCONSOLIDATED-DRAINEDTRIAXIAL TESTDECEMBER, 1977 FIG.OF NEW HAMVTHIRITC T 2.50.5STRESS STRAIN002468101214161820AXIAL STRAIN,%TEST S290% Compaction= 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF ^EW RHAUMPCS4IR15 R A LB A C K F I L LGEOTECHNICAL ENGINEERS INC.PROJECT 77386DECEMBER, 1977 FIG. A21.50-0.5VOLUME STRAINCONSOLIDATED-DRAINEDTRIAXIAL TEST S2 2.5STRESS-1.5,VOLUME-2.0.02468101214161820AL STRAIN,%TEST S3 90Compaction3c = 6.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386DECEMBER, 1977 2.51.51.00.5064202VOLUME STRAIN681012141618AXIAL STRAIN,%TEST S495% Compaction3c = 0.5T R I A X I A L^aSERVICE COMPANYICONSOLIDATED-DRAINEDOF NEW HAMPSHIRESTRUCTURAL BACKFILLPROJECT 77386GEOTECHNICAL ENGINEERS INC .YINCHESTER,MASSACHUSETTSDECEMBER, 1977 1.5.1.00.5 . .STRESS0VOLUME STRAIN2461012141620AXIAL STRAIN,%TEST95% Compaction2.0SERVICE COMPANYCONSOLIDATED-DRAINEDTRIAXIAL TESTSOF NEW HAMPSHIRETEST,STRUCTURAL BACKFILLENGINEERS INC.PROJECT 77386 DECEMBER, 6PROJECT 77386I DECEMBER, 1977 FIG. A2.5STRESS STRAIN-1.024681012741618 20VOLUME STRAINAXIAL STRAIN,%TEST S695% Compaction= 6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,SEOTECHNICAL ENGINEERS INC.1TRIAXIAL TESTSSTR UCTURAL BACKLL 4.03.02.0I>3=1.64E6260 psi4050 psi.1.00.60.40.200.40.81.21.6AXIAL STRAIN,%TEST90% Compaction= 0.5CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPROJECT 77386DECEMBER,1977 FIG. A7ENGINEERS INC.MASSACHUSETTSSERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILL 8.0= 5.883E014220 psi11090 psi6.04.0I2.00-0.1-0.2-0.3-0.400.81.21.62.0AXIAL STRAIN,%TEST S290% Compaction= 2.0SERVICE COMPANYOF NEW HAMPSHIRET R I A X I A L TESTSSTRUCTURAL BACKFILLENGINEERS INC.VVINCHESTER, MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S2Expanded ScalesPROJECT 77386DECEMBER,!977 FIG.
AXIAL STRAINTEST S390% Compaction6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIRE,STRUCTURAL BACKFILLPROJECT 77386TESTSTEST S3Expanded ScalesENGINEERS INC.WINCHESTER, MASSACHUSETTS 3= 2.34E013510 psiE9600 psi= 0.3350= 0.3500.40.81.2162.0AXIAL STRAINTEST S495% Compaction= 0.5SERVICE COMPANYOF NEW HAMPSHIRETESTSSTRUCTURAL BACKFILLENGINEERS INC.MASSACHUSETTSCONSOLIDATED-DRAINEDTRIAXIAL TEST S4Expanded ScalesPROJECT 77386IFIG.
TEST95% Compaction3c = 2.0TESTSSKTRUCFTURALILLPROJECT 77386CONSOLIDATED-DRAINEDTRIAXIAL TEST S5Expanded ScalesF I G .SERVICE COMPANYOF NEW HBAMPSAHIRECMASSACHUSETTSENGINEERS INC.-0.20.40.2AXIAL STRAIN,%32133016140=7.96kg/cm-psipsi8.062.I4.
I-0.1-0.3,1 6 . 012.04.08.0 .AXIAL STRAINTEST95% Compaction= 6.0PROJECT 77386DECEMBER,1977 FIG.CONSOLIDATED-DRAINEDTRIAXIAL TESTExpanded ScalesPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.NINCHESTER, MASSACHUSETTSTESTSSTRUCTURAL BACKFILL APPENDIX 246814161820AXIAL STRAIN , %-SSPA81012141618TEST90%Compactiona3c1412108606PUBLIC SERVICE COMPANYOF NEW HAMPSHIRESTRUCTURALTRIAXIALPROJECTTESTSBACKFILL77386IDECEMBER,1977CONSOLIDATED-UNDRAINEDTRIAXIAL TEST 3.53.02.51.5STRESS PA0.5TEST90% Compactiona 3c002468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSOFSHf %P ^ H^R f U RTRIAXIAL TESTA LB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG. B2 1.25"1.0DO.750.25STRESS-S TRAINSPA01.00.500.751.001.251.501.752.002.252.TEST90% Compaction6.0.. 2524681214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYOF NEW HOMPSMIRE CPROJECT 77386DECEMBER, 1977 FIG.T R I A X I A L TESTSSTKRUCTFURALILLCONSOLIDATED-UIJDRAINEDTRIAXIAL TESTENGINEERS INC.WINCHESTER, MASSACHUSETTS STRESS PASTRESS0.250.500.751.001.251.501.752.002.25TESTCompaction3c6.002468101214161820AXIAL STRAIN ,PUBLIC SERVICE COMPANYCONSOLIDATED-UNDRAINEDTRIAXIALTESTSOF NEW HAMPSHIRETRIAXIAL TESTBACKFILLSTRUCTURAL,ENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG. B4PROJECT 77386 s TRESS PASTRESS-S05101520253035404550TEST90% Compactiona 3c0024681012 14 1618 20AXIAL STRAIN, %PUBLIC SERVICE COMPANYTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDO F N E ^l 0 ALY PCS1^I RUE R ATRIAXIAL TESTLB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSPROJECT 77386DECEMBER, 1977 FIG. B5 S ESS PA-S10121416TEST90% Compactiona 3c= 2.02468101214161820AXIAL STRAIN , %PUBLIC SERVICE COMPANYTRIAXIAL TESTSOS TF RNEU CHATP UHIRREA LTRIAXIAL TESTB A C K F I L LENGINEERS INC.WINCHESTER,MASSACHUSETTSFIG.PROJECT 77386 0.502468lo14161820AXIAL STRAIN ,ENGINEERS INC..WINCHESTER,MASSACHUSETTS00.51.01.52.02.53.03.54.04.55.PROJECT 77386TEST90% Compaction6.0DECEMBER, 1977 FIG. BSTRESS PA TRIAXIAL TESTSSTRUCTURAL BACKFILLPROJECT 773860.40 . 81.21.6AXIAL STRAIN,4.01.03 . 020TEST90% Compaction= 0.53cCONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESPUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERS INC.WINCHESTER, MASSACHUSETTS 4.03.0bI20.1.0AXIAL STRAIN, %TEST90% Compactiona 3c = 2.0PUBLIC SERVICE COMPANYTRIAXIAL TESTSOF NEW HAMPSHIRETRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESENGINEERS INC.WINCHESTER, MASSACHUSETTS1PROJECT 77386DECEMBER,1977 CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER,19778.00.40.81.2AXIAL STRAIN,.%TEST90% Compaction ,6.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREE N G I NWINCHESTER, MASSACHUSETTST R I A X I A L TESTSSTRUCTURAL BACKFILLE E R SI N C;PROJECT 77386 AXIAL STRAIN,ENGINEERS INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977 FIG00.40.81.21.68.0TEST90% Compaction= 6.0.6.03c PUBLIC SERVICE COMPANYOF NEW HAMPSHIRECONSOLIDATED-UNDRAINEDT R I A X I A L TESTSTRTAXTALISTRUCTURAL BACKFILLSCALESTEGEOTECHNICALCHNICA L ENGIENGINERSNEER SINC.INC.WINCHESTER, MASSACHUSETTSPROJECT 77386DECEMBER,1977AXIAL STRAIN,8.02.0TEST90% Compaction.3c= 0.5 00.40.81.21.62.0AXIAL STRAIN,20164I12TEST90% Compaction3 c = 2.0PUBLIC SERVICE COMPANYOF NEW HAMPSHIREENGINEERSWINCHESTER, MASSACHUSETTSTRIAXIAL TESTSCONSOLIDATED-UNDRAINEDTRIAXIAL TESTSTRUCTURAL BACKFILLEXPANDED SCALESPROJECT 77386IDECEMBER, 1977 AXIAL STRAIN,20.016.04.012.08.000.81.21.62.0TEST90% Compaction= 6.0 kg/cm.CONSOLIDATED-UNDRAINEDTRIAXIAL TESTEXPANDED SCALESDECEMBER, 19773c ENGINEERS INC.1017 MAIN STREETWINCHESTERMASSACHUSETTS 01890729-1625February 14, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th FloorManchester, NH 03105
Subject:
Interim Test Results on Sand-Cement BackfillStation
Reference:
Preliminary Report, Compression Tests onStructural Backfill and Sand-CementStation,January 24, 1978
Dear Mr.The purpose of this letter is to present data on moduli deter-mined on sand-cement backfill at the request of United Engineersand Constructors Inc. The data herein supplements the data in thereference and will be incorporated in the completed version of thatreport.Themodulus values were submitted to Mr. Pate1ofby telephone on February 13,
1978.The stress strain curves for three unconfined compression testson cylindrical specimens are shown in the enclosed Fig. 15 and thetest data are summarized in the enclosed Table 5.The following values of the coefficient ofreactionwere computed for the cube and cylindrical specimens cured for 28days..
Mr. JohnFebruary 14, 1978FOR SAND-CEMENT BACKFILL28-DAY CURETabulated values are in psiEffectiveVerticalStress atAllowable Diameter Strain, Springline0.020.10.30.5CUBE SPECIMENS100,000CYLINDRICALSPECIMENS200,00089,00060,00036,000The stress strain curves for the cylindrical specimens show aninitial straight line portion withhigh modulus of elasticity.At axial strains of about 0.03% there is a break in the curves and asecond straight line is followed up to near the peak strength.Thetangent modulus of this second straight line portion of the curves isabout one-third of the initial modulus.Fig. 16 shows the variation ofthe secant modulus with axial strain for the unconfined tests on cylin-drical specimens.Seating problems occurred in the tests on the cube specimens, asseen in Figs. 13 and 14 of the above reference, and thus the high initialmodulus observed for the cylindrical samples was not observed for thecubes. However, the second straight line slope for the cylindricalspecimens in Fig. 15 is in good agreement with the straight line portionof the curves for the cube specimens.The compressive strength of thecube specimens is somewhat higher than that of the cylindrical specimens,probably as a result of the more significant end restraint of the cubespecimens.For these two reasons we feel that the results of tests oncubes and cylinders are consistent with each other, but that the resultsfor tests on cylinders are more reliable and should be used to establishmoduli ofreaction.
Mr. JohnFebruary 14, 1978We have also provided by telephone various friction coefficientsand estimates of shear wave velocities in the compacted soil. Thesedata will be confirmed in writing at a later date.Sincerely yours,Steve J. PoulosPrincipalEncl.cc:R.YAEC w/l encl.D.w/l encl.A. Desai,w/l encl.
ConfiningCompressiveStrainInitialStressStrengthAtModulus ofPeakElasticitykscpsi%psiCureTestUnitTimeNo.WeightWetdaysTABLE 5 COMPRESSION TESTS ON 2.8-IN.-DIAMETER.SAND-CEMENT SPECIMENS, 5% CEMENTSTATION2828-O-l126.20.002828-O-2124.80.002828-O-3124.10.0091.00.6588.8.0.58106.10.8075,00052,20034,30095.3Avg 50,500Geotechnical Engineers Inc.Project 77386February 7, 1978 StationTriaxial TestsProject 77386February 1978Fig. 15Engineers Inc.Winchester, MassachusettsPublic Service Company ofSand-CementBackfillSpecimens Tested:specimens28-day cureUnconfined testsStrain control loading at1.10.81.6AXIAL STRAIN ,Sand-Cement Mixture:Xa1part cement16.18 parts sand (oven-dry)2.79 parts waterCOMPRESSION TESTS2.8-IN.-DIAMETER SPECIMEN5% CEMENT, 28-DAY CURE Winchester, MassachusettsProject 77386600 .00.20.40.81.01.2STRAIN AT PEAKAVERAGE= ksAXIAL STRAIN,,Triaxial TestsSand-CementBackfillStationPublic Service Company ofNew HampshireGeotechnical Engineers Inc.February 197816SECANT MODULUS VS STRAINSPECIMENS5% CEMENT,CURE 203060500AXIAL STRAIN,, %0.20.4=
ENGINEERS INC.1017 MAIN STREET. WINCHESTERMASSACHUSETTS 01890Mr. JohnPublic Service Co. of New Hampshire1000 Elm Street-11th floor..Manchester, NH 03105
Subject:
Interim Test Results on Sand-Cement'BackfillStation
Reference:
Preliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978Bear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letter of February 14.These triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 33 days instead ofthe intended 28 days because of the February 6, 1978 blizzard herein Boston. The test data are summarized in a revised Table 5 andthe stress strain curves are presented in Fig. 17.The modulus and strength data were estimated for 28-day curingon the basis of the rate of change of modulus and strength withtime as measured using the cube specimens (see referenced report).The estimated values of strength and modulus for 28-day cure alsoare shown in Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letter of February14. The following table lists all values obtained to date for thesand-cement specimens.
FOR SAND-CEMENT BACKFILLCURE, 5% CEMENTGEOTECHNICALINC.cc:R. Pizzuti, YAEC w/l encl.w/l encl.A. Desai,w/l encl.D.. Patel,w/l encl.Mr. JohnFebruary 27, 1978Tabulated values are in psiEffectiveAllowable Diameter Strain, %VerticalStressatSpringlinepsi0.10.30.5.CUBESPECIMENS0100,000.CYLINDRICALSPECIMENS0200,00089,00060,00036,00042.7138,000163,000129,600Sincerely yours,Steve J. PoulosPrincipalGC:msEncl.
TABLE 5COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%STATION372.3652.1035,00033,6003762.4033,30036931,7003641.4040,00035738,40042.742.7124.8332833283328EstimatedTestNo.days28-O-lUnitWeightWetConfiningCompressiveStrengthpsiStrainInitialatModulus ofPeakElasticitypsi126.20.00910.6575,0002828-O-2124.80.00890.5852,200.2828-O-3124.10.001060.8034,300NOTE: 1) The percentage of cement is computed as the ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.2) The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.Geotechnical Engineers Inc.Project 77386February 7, 1978Revised February 24, 1978 3= 42.7 psi0.8 IIII 0051.0I.52.02.53.03.54 . 0AXIAL STRAIN, %Project 77386Feb. 23, 1978Fig.17StructuralBackfillTriaxial Tests2.8-IN.-DIA., 5% CEMENT33-DAY CURE,=SAND-CEMENT SPECIMENSPublic Service Company ofNew HampshireEngineersWinchester,Massachusetts 1017 MAIN STREET. WINCHESTER. MASSACHUSETTS 01890729-1625March 10, 1978Project 77386File No. 2.0Mr. JohnPublic Service Co. of New Hampshire.1000 Elm Street11th FloorManchester, NH 03105Interim Test Results on Sand-Cement Backf illStationPreliminary Report, Compression Tests OnStructural Backfill and Sand-CementStation, GEI, January 24, 1978
Dear Mr.The purpose of this letter is to present additional data onmoduli determined on sand-cement backfill.These data supplementthe data in the reference and in our letters of February 14 and27.Three triaxial tests were performed on cylindrical specimensof sand-cement. The specimens were cured for 28 days and weretested under a confining stress of 7.1 psi.The test data aresummarized in a revised Table 5.The values of the coefficient ofreaction were com-puted for several strain levels in the same manner as those shownin the preliminary report of January 24 and the letters of February14 and 27. The following table lists all values obtained to datefor the sand-cement specimens:
Mr. JohnMarch 10, 1978FOR SAND-CEMENT BACKFILL28-DAY CURE, 5% CEMENTTabulated values are in psiEffectiveVerticalAllowable Diameter Strain, Stress atSpringlinepsi0.10.30.5CUBE SPECIMENS01 0 0, 0 0 0CYLINDRICAL SPECIMENS0200,00089,00060,0007.1115,000106,00079,60042.7138,000163,000129,600*Modulus value determined at strains greater than the strain at peakcompressivestrength.Geotechnical Engineers Inc.Project 77386Revised March 6, 1978 Mr. JohnMarch 10, 1978,GEOTECHNICALINC.GC/SJP:msEncl.cc: R. Pizzuti, YAECD.A. Desai,D. Patel,Three unconfined tests were performed on cube specimens ofsand-cement cured for 90 days. The test data are summarized ina revised Table 4.The stress-strain curves for the additional tests will betransmitted as soon as they have been drafted.Sincerely yours,Steve J. PoulosPrincipal UnitWeightWetCureTimedaysTestNo.TABLE 4 UNCONFINED TESTS ON 2-IN. CUBE SAMPLESOF SAND-CEMENT, 5 % CEMENTSTATIONUnconfinedStrengthpsiStrainModulusAto fPeakElasticity*%psi28907-l124.07-2123.97-3126.228-l127.428-2126.228-3126.890-l124.490-2124.590-30.8010,6000.9210,1100.8313,650Avg 11,450141.60.67.33,3300.7719,1300.8722,760 Avg 135.00.951.080.84Avg 28,200Avg 25,07026,32027,03031,250*Modulus computed for the straight line portion of the stress-straincurve, neglecting any curvature at origin, which may be affected byinitial seating strains.Geotechnical Engineers Inc.Project 77386January 23, 1978Revised6, 1978 126.2124.8124.175,00052,20034,3002828-O-l2828-O-22828-O-30.0910.650.0890.580.0.1060.80TABLE 5--COMPRESSION TESTS ONSAND-CEMENT SPECIMENS, 5%CureTimeNo.daysUnitWeightWetConfiningCompressiveStrengthpsiStrain.InitialatModulus ofPeakElasticitypsi283333283342.742.7423722.1035,00028282 8281)372.3762.4033,3001.4040,00039,6007.11197.1134124.3The percentage ofthe ratio of theweight of cement to the total weight of sand, cement, andwater, and then multiplying that ratio by 100.The strengths and moduli for 28-day cure was estimatedbased on the rates of change measured for the cubespecimens.34,60037632,9003643640.6032,6000.9022,9000.9717,400Geotechnical Engineers Inc.Project 77386February1978Revised-February 24, 1978Revised March 6, 1978 UPDATED FSARAPPENDIX 2NGEOTECHNICAL REPORT TEST FILL STUDY OF QUARTZITE MOLE CUTTINGS The information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
William R.Senior EngineerStevePrincipalTEST FILL STUDYOFQUARTZITE MOLECUTTINGSSubmitted toPublic Service Company of New HampshireSubmitted byGeotechnical Engineers Inc.1017 Main StreetWinchester, Massachusetts 01890July 13, 1979Project 76301 81010101111111314TABLE OF CONTENTSPage No.LIST OF TABLESLIST OF FIGURES1.INTRODUCTION1.1 Purpose1.2 Background1.3 Summary2.CONSTRUCTION OF TEST FILLS2.1 Gravelly Sand2.2 Molecuttings (Controlled Placement)2.3 Molecuttings (No Special Controls)2.4 Stratified Molecuttings and Gravelly Sand3.PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand3.2 Molecuttings (Controlled Placement)3.3 Molecuttings (No Special Controls)3.4 Stratified Molecuttings and Gravelly Sand4.PLATE LOAD TESTS5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS5.1 Grain-Size Limits5.2 Lift Thickness5.3 Determination of In-Place Dry.Density5.3.1 Gravelly Sand5.3.2Molecuttings5.4 Determination of Percent Compaction5.5 Water Content ControlTABLESFIGURESAPPENDIX ARECOMMENDEDFOR PLACEMENTAND FIELD CONTROL OF MOLECUTTINGSAPPENDIX BPLATE LOAD TESTS LIST OF TABLESTable 1Summary of Field Density TestsGravelly Sand Test FillTable 2Summary of Field Density TestsMolecuttings (Controlled Placement) Test FillTable 3Summary of Field Density TestsMolecuttings (No Special Controls) Test FillTable 4Summary of Field Density TestsStratified Molecuttings and Gravelly Sand Test FillTable 5Summary of Plate Load Tests Results LIST OF FIGURESFig. 1Plan View of Test FillsFig. 2Profile of Test FillsFig. 3Profile of Test FillsFig. 4Compaction CurvesGravelly SandFig. 5Grain Size CurvesGravelly Sand Test FillFig. 6Compaction CurvesMolecuttings.Fig. 7Grain Size CurvesSamples of MolecuttingsFig. 8Modulus of Elasticity vs Percent CompactionMolecuttings.Fig. 9Water Content Sand ConeNuclear Density MeterGravelly SandFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryGravelly SandFig.Water Content Sand Cone vs Nuclear Density MeterDet., MolecuttingsFig.Sand Cone vs Nuclear Density Meter Det. In-PlaceDryMolecuttings the same percent compaction.problem was addressed byInvestigation of the resistivityINTRODUCTION1.1 Purpose The intake and discharge tunnels atStation arebeing excavated using a tunnel boring machine, more commonlytermed a mole. The excavated material from the mole is awidely-graded crushed stone commonly termed tunnel muck, which,for this report, shall be termed "molecuttings."The purpose of the test fill study was to determine if thequartzite molecuttings obtained from-the tunnel excavationscould be used for Safety and Nonsafety-Related Structural Fill.Construction of the test fills provided the opportunity to ob-serve the behavior of the molecuttings during placement andobtain data necessary to develop procedures to control the com-paction of the molecuttings during placement.1.2 Background The molecuttings from the quartzite bedrock in the tunnelsare widely-graded crushed stone containing up to 13% passingthe No. 200 sieve.The grain size curve of the molecuttingsplots below the lower limit of the Safety and Nonsafety-RelatedStructural Backfill specification.The resistivity of thecuttings is generally below the specified minimum value of10,000Thus, although the molecuttings appearedsuperior to the gravelly sand structural fill as a backfillmaterial, it was rejected because the gradation and resistivityrequirements did not comply with the specifications.Useofthe molecuttings for Safety and Nonsafety-Related StructuralFill required that selected tests be performed which would demon-strate that the molecuttings were as good or better than thepresently used gravelly sand when both materials were placed atThe Safety and Nonsafety-Related Structural Fill is usedfor backfill around pipes and conduits, under floor slabs, roads,etc.For these applications the deformation characteristics ofthe backfill will control the soil support of the pipes andsettlements of structures. One method of determining the defor-mation properties of a soil is by determining the soil modulusby the use of a plate load test.Plate load tests were performedon carefully constructed test fills consisting of (a) gravellysand, (b) molecuttings, anda test fill of essentially alter-nating layers of gravelly sand and molecuttings which herein willbe referred to as the stratified gravelly sand and molecuttings test fill The modulus from each test fill was used as a means of comparingthe desirability of the molecuttings versus the gravelly sand foruse as Safety and Nonsafety-Related Backfill.The molecuttings are widely graded and containhigh percentages of stone retained on thesieve.In manycases the percentretained on thesieve exceeds theallowable limits for the Modified AASHO compaction testThus, it was necessary to determine by means of field and labora-tory tests performed during construction of the test fill howconstruction control of the placement of the molecuttings shouldbe handled.., 1.3 Summary The results of the plate load tests indicate that thecuttings will provide superior support for pipes and structuresthan the gravelly sand currently accepted for Safety andsafety-Related Structural Fill when both materials are placed atthe same percent compaction.The molecuttings and gravelly sandwill provide about equivalent deformation properties when thepercent compaction of the molecuttings is as much as 2 to 3%lower than the gravelly sand.Therefore, the use of molecuttingsfor Safety and Nonsafety-Related Structural Fill is recommended.Further, it is recommended that the percent compaction of themolecuttings for Safety and Nonsafety-Related Structural Fill be95% andrespectively.The molecuttings used in constructing these test fills werewidely graded crushed stone with up to 7% passing the No. 200sieve.The water content of the material varied from 3 to 4% upto 10% during placement.Because of the grain-size distributioncompaction of the molecuttings was sensitive to fluctuations inthe water content of the material. Based on data obtained fromtests performed during construction of the test fills, limitationson the grain-size distribution and water content'of thecuttings during placement have been recommended in Section 5.Construction of the test fills indicated that placement ofthe molecuttings can be controlled by modifying standard testingprocedures.The in-place dry density can be measured using thenuclear density meter and the laboratory reference dry densitydetermined by modifying the currently specified compaction tests.Details of the construction of the test fills, performanceand results of the plate load tests, and procedures for controlof placement and compaction of molecuttings are presented in thefollowing sections. 2.CONSTRUCTION OF TEST FILLSFour test fills were constructed for this study.Theorientation of the test fills is shown in Fig. 1.The soilsand details of placement for each test fill is presented below.2.1 Gravelly Sand Gravelly sand satisfying the requirements for Safety andNonsafety-Related Structural Fill Specifications 9763-8-5 and9763-8-4 was placed in 8-in. -thick loose lifts and compactedto a minimum of 95% of the maximum dry density as determined byASTM D1557, Method D.Satisfactory compaction was generallyachieved by applying water to the surface of the loose lift andcompacting with six coverages with the Mikasa double drum roller.Eight lifts of gravelly sand were placed and compacted, result-ing in a total height of about 4 ft.2.2 Molecuttings (Controlled Placement)The construction of this test fill was controlled to achievethe compaction requirements of Safety and Nonsafety-RelatedStructural Fill (i.e., 95% of the maximum dry density as deter-mined by ASTMMolecuttings were placed in 8-in. loose lifts and compactedto 95% compaction. To achieve 95% compaction, control of thewater content to within a few percent of the optimum water con-tent, and numerous coverages with the Mikasa double drum rollerwas required. Attempts at controlling the water content includedmixing of wet and dry molecuttings and adding water tocuttings with water contents 2 to 3% below optimum. Molecuttingsplaced at water contents several percent higher than optimumcould not achieve 95% compaction until sufficient drainage hadreduced the water content to near the optimum value.Eight liftsof molecuttings were placed and compacted resulting in a totalheight of about 4 ft.2.3 Molecuttinqs (No Special Controls)Construction of this test fill involved the placement of themolecuttings with limited control of water content and a specifiedcompactive effort. The molecuttings were generally placed inG-in. loose lifts and compacted by six coverages with the Mikasadouble drum roller.In some instances, water content control waslimited to permitting drainage of a compacted layer overnight be-fore placement of the succeeding layer.Eight lifts ofcuttings were placed and compacted. 2.4 Stratified Molecuttings and Gravelly Sand The first three lifts of this test fill were constructedthe same way as the test fill of Molecuttings (No Special Con-trols). The water content of the molecuttings placed for thethird lift was about 3% higher than optimum. The surface ofthe third lift was saturated and became severely rutted duringcompaction.Sandwiching layers of gravelly sand between layersof molecuttings was done to determine (1) if the gravelly sandprovided drainage of sandwiched layers of molecuttings and (2)the feasibility of constructing a backfill of stratifiedgravelly sand and molecuttings (which may be required in thezone of frost penetration).Therefore, lifts 4 and 6 were con-structed using gravelly sand.Lift 4 was compacted with sixcoverages of the Mikasa double drum roller and lift 6 was com-pacted to at least 95% compaction. Molecuttings for lifts 5, 7and 8 were generally placed in 8-in. loose lifts with limitedwater content control and compacted with six coverages of theMikasa double drum roller. 3. PERCENT COMPACTION OF TEST FILLS3.1 Gravelly Sand The percent compaction of each lift was determined by per-forming in-place density tests and laboratory compaction tests.The average percent compaction of the gravelly sand test fillwas 97.4%.The in-place density for each lift, after compaction, wasdetermined by performing two 6-in. -diameter Sand Cone (SC)tests and three Nuclear Density Metertests.Theplace density determined by the NDM was generally performed atprobe depths of 4 in. and 8 in.The two SC tests were performedadjacent to two of the NDM tests to provide a comparison of thewater content and dry density measured by each 'method.The SCand NDM tests were generally performed within a 5-ft radius ofthe plate load test location. .One-point compaction samples were obtained adjacent to theSC and NDM test locations. The one-point samples were compactedin accordance with ASTM D1557, Method D.The maximum dry densityfor the one-point sample was determined by plotting the one-pointdry density on a family of curves for the gravelly sand and in-terpolating the maximum dry density.The percent compaction wascomputed by dividing the in-place dry density by the correspondingone-point compaction determined maximum dry density.Table 1presents the summary of the percent compaction achieved in thetest fill.A profile of the test fill and the average percentcompaction for each lift is shown on Fig. 2.Three compaction tests were performed in accordance withASTM D1557, Method D, on bag samples of gravelly sand obtainedfrom material placed in lifts 2, 4 and 7.The compaction curvesand related grain-size curves performed by Pittsburgh Testing Labsare shown on Figs. 4 and 5, respectively.3.2 Molecuttings (Controlled Placement)The average percent compaction achieved for this test fillwas 96.7%.The in-place density of each lift after compactionwas determined by performing several NDM tests and, when thesoil conditions were acceptable, oneSC test.The SC test was performed adjacent to a NDM test to provide acomparison of the water content and dry density measured by eachmethod. Observations in the field and data from tests indicatedthat the hole excavated for the SC test tended to squeeze in orreduce in volume when the molecuttings were placed and compacted at water contents above or near optimum.Results from the SCtests when these conditions existed gave unreasonably high drydensities, and, as a result, SC tests were considered valid onlywhen they were performed in areas where the water content of themolecuttings was less than 5%. A more complete discussion ofthis problem is presented in Section 5.The SC and NDM testswere generally performed within about a 5-ft radius of the plateload test.Generally, several NDM tests were required before a lift ofthe molecuttings was compacted to a dry density that was esti-mated to provide 95% compaction. One-point compaction sampleswere obtained adjacent to the series of NDM and SC tests that, indicated about 95% compaction had been achieved.The one-pointsamples were compacted in accordance with ASTM D1557, Method C,except the minusmaterial was included for compaction.The maximum dry density for the one-point sample was determinedby plotting the one-point dry density on a family of compactioncurves for molecuttings and interpolating the maximum dry density.Correction of the in-place dry density to account for theplusmaterial, which was removed for the laboratory test,was necessary in order to determine the percent compaction. De-tails of the correction procedure are presented in Appendix A.The percent compaction was computed by dividing the correctedin-place dry density by the corresponding maximum dry densitydetermined by the one-point compaction technique.Table 2 pre-sents the summary of the percent compaction achieved in thetest fill. A profile of the test fill and the average percentcompaction for each lift is presented in Fig. 2.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on l&-in. sieveon bag samples of molecuttings from lifts 4 and 6.The compac-tion curves and related grain-size curves are shown on Figs. 6and 7, respectively.3.3 Molecuttings (No Special Controls)The average percent compaction of this test fill was 93.0%.The water content of the molecuttings during placement was gen-erally above optimum and was not controlled during compaction.Sand Cone tests to determine the in-place dry density were notperformed because of the inaccuracy in performing the test inmolecuttings compacted at water contents near or above optimum.The in-place dry density was determined by performing at least two and most usually three to five NDM tests at probe depthsof 4 and 8 in.The NDM tests were generally performed withina 5-ft radius of the plate load test location.One-point compaction samples were obtained adjacent'to theseries of NDM tests that indicated the next lift of molecuttingscould be placed.In some cases after a lift had been compacted,NDM tests performed, and one-point samples obtained, the liftwas permitted to drain overnight and additional NDM tests takenin the morning. One-point compaction samples generally were notobtained for the NDM tests performed after drainage. The pro-cedure to compute the percent compaction for each in-place den-sity test was the same as described in the previous section.Table 3 presents the summary of the percent compactionachieved in the test fill. A profile of the test fill and theaverage percent compaction for each lift is presented in Fig. 3.Two compaction tests were performed in accordance with ASTMD1557, Method C, except the minusmaterial was includedand there was no limit on the percent retained on thesieve on bag samples obtained from lifts 2A and 7A. The com-paction curves and the grain-size curve for lift 2A are shownon Figs. 6 and 7, respectively.3.4 Stratified Molecuttings and Gravelly SandThe average percent compaction of the gravelly sand andmolecuttings test fill was 92.8%.Molecuttings were used forlifts 1, 2, 3, 5, 7, and 8 for this test fill.The in-placedry density and percent compaction of the molecuttings was deter-mined in accordance with the procedure described in the previoussection. Lifts 4 and 6 of the test fill were constructed usinggravelly sand. The in-place density for lift 4 was determinedby four NDM tests. One SC test and 3 NDM tests were performedin lift 6. The maximum dry density and computation of the per-cent compaction at each in-place density test location was asdescribed in the section for gravelly sand.Table 4 presentsthe summary of the percent compaction in the test fill. A pro-file of the test fill and the average percent compaction of eachlift is presented in Fig. 3. 4.PLATE LOAD TESTSFive plate load tests were performed on the four testfills.The plate load test number, test fill and date of thetest is presented below.Plate Load Test No.Test FillDate of Test1Gravelly SandJune 7, 19792MolecuttingsJune 14, 1979(No SpecialControl) .StratifiedJune 15, 1979cuttings andGravelly SandMolecuttingsJune 18, 1979(ControlledPlacement)5Molecuttings(No SpecialControl)The locations of the tests are indicated on Fig. 1 and de-tails of the procedure are presented in Appendix B.In briefthe procedure was as follows:an-diameter steel platewas generally placed 12 in. below the surface of the test filland loaded to produce contact stresses to 4 tsf and then to 12Deflections of the plate were measured and recorded.The results of the plate load tests are presented in Figs.B2 through B6. Values of Young's Modulus, E, were calculatedfrom the results of the plate load tests using elastic theory.A description of the analysis is presented in Appendix B. Asummary of the modulus calculated for each test is presented inTable 5.The percent compaction indicated in Table 5 representsthe average percent compaction of lifts within the zone of signi-ficant stress increase due to the load on the plate.For anin. -diameter plate this zone is aboutto 36-in.-thick.The soil modulus determined by the plate load test vs per-cent compaction is plotted on Fig. 8.The results indicate thatthe molecuttingshave a much higher modulus than the gravelly sandwhen both materials are compacted to the same percent compaction.In fact, the modulus of the molecuttings compacted to 93% compac-tion is approximately equivalent to the modulus of the gravellysand placed at 97% compaction.Plate Load Test No. 5 (PLT-5) wasperformed 13 days after and about 4 ft away from Plate Load TestNo. 2 (PLT-2).The soil modulus for PLT-5 was about two timesJune 27, 1979 the modulus for PLT-2. The increase in modulus may have beencaused by densification of the molecuttings as a result ofdrainage over the 13 day period between the performance of thetwo tests. Assuming that the molecuttings were saturated afterPLT-2 and the water content reduced by 1% during a period of 13the in-place dry density would have increased by 2 to 3 pcfor about a 1 to 2% increase in the percent compaction.Themodulus for PLT-5, as a result of the densification, nearly plotson the line from PLT-2 to PLT-4.Test PLT-3 was performed on the stratified molecuttings andgravelly sand test fill. The average percent compaction of themolecuttings and gravelly sand was 92.5 andrespectively., Plate load tests, PLT-2 and PLT-1, were performed on separatetest fills of molecuttings and gravelly sands compacted to aboutthe same percent compaction and the moduli were 7,300 psi and 10,100respectively.The moduli determined for the stratified testfill, however, was 17,000 psi.Based on the results of PLT-1 andPLT-2 the anticipated modulus determined by FLT-3 was between 8and 10,000 psi.The high modulus measured by PLT-3 may have beencaused by one or more of the following factors:1.Distribution of the load may have been more rapid forthe layered fill than in a homogeneous fill, and2.Drainage of the molecuttings and related increases indry density and modulus may have accelerated faster inthe stratified test fill than in the homogeneouscuttings (No Special Controls) test fill due to drainagethrough the gravelly sand layers.
- 5. PLACEMENT AND FIELD CONTROL OF MOLECUTTINGS The purpose of this section is to present recommendationsfor the placement and field control of molecuttings based onfield and laboratory data obtained during construction of thetest fills.Review of the data obtained provided the information neces-sary to make recommendations on the limits for grain size, liftthickness, determination of in-place density and percent compac-tion, and control of water contents of the molecuttings. Adiscussion of each of the items is presented below.5.1 Grain-Size LimitsGrain-size analyses were performed on thre'e samples of themolecuttings used for the test fills.The grain-size curvesare presented on Fig. 7.The molecuttings were generally widelygraded with uniformity coefficients of 45 to 100.The maximumparticle size was generally less than 3-in.-diameter and thepercent by weight passing the No. 200 sieve was from 5 to 7%.Based on these and other grain-size analyses recommendations forgradation requirements were developed and are presented inAppendix A.5.2 Lift ThicknessThe molecuttings were placed in 8-in.-thick loose liftsduring construction of the test fills. Observations made duringplacement of the molecuttings indicated that the ability toachieve a specific percent compaction was mostly affected by thewater content of the material rather than the thickness of thelift. When the molecuttings were placed at water contents aboveoptimum, a specific degree of compaction generally was notachieved until the water content was reduced to'or below theoptimum water content as a result of drainage.The time requiredfor drainage is a function of the lift thickness and, therefore,where 95% and 93% compaction is required, lift thicknesses of8-in. andare recommended.Thethick loose lift inareas where 93% compaction is required was recommended based onthe fact that the average percent compaction of 93.0% was achievedfor the molecuttings (No Special Controls) test fill without thebenefit of extensive compactive efforts.
5.3 Determination of In-Place Dry Density The nuclear density meterprovides a much fasterdetermination of the field in-place dry density and water con-tent than the sand cone (SC).The accuracy of the NDM testsperformed in the gravelly sand and molecuttings was verifiedby comparing the results of adjacent NDM and SC tests.5.3.1 Gravelly Sand Generally, two SC tests were performed adjacent totwo NDM tests on each lift of the test fill to com-pare the in-place dry density and water contentmeasured by each method.. The in-place water con-tent determined by the sand cone versus nuclear den-sity meter is plotted on Fig. 9.The data indicatethat both methods measure essentially the same watercontent at values less than 8% and, as the water con-tent increases, the NDM measures a lower value thanthe SC. As a result, a correction was applied tothe water content measured by the NDM to compute thein-place dry density... A plot of sand cone versusnuclear density meter determined in-place dry densityis shown on Fig. 10.The correlation of the densi-ties determined by each method was considered to bepoor.The correlation may have been improved ifmore frequent moisture checks had been performed dur-ing construction of the test fill.5.3.2Molecuttings Twelve-inch-diameter sand cone tests were performedin the molecuttings to reduce the effects that themaximum particle size and percentage of materiallarger than thesieve would have on in-place drydensity determination. The in-place dry density andwater content determined by the SC test was comparedto the results from adjacentNDM tests.Comparison of the results indicated the water contentdetermined by the NDM averaged 1.7% higher than thatdetermined by the sand cone.The 1.7% difference inwater contents was confirmed by performing water con-tent checks at random NDM test locations. A 1.7% biascorrection was applied to the water contents determinedby the NDM. A plot of sand cone determined water con-tent versus nuclear density meter water content (with a1.7% bias correction) is presented on Fig. 11.
The plot shows there is a good correlation betweenthe sand cone and nuclear density meter (after biascorrection) water content determinations.A secondwater content check was made on molecuttings. afterthe test fill was completed which indicated thatthe bias had increased to 2.5%.Because the watercontent bias changed significantly within a periodof two weeks periodic checks of the bias arerecommended.The in-place dry density determined by the sand conetest and the 8-in. NDM test after correction for thewater content bias is plotted on Fig. 12.The soliddots and dashed circles represent in-place dry den-sity measurements at water contents less than 5% andgreater thanrespectively.The data indicatethat there is good correlation of dry densities deter-mined by both methods at water contents less than 5%and that the SC measured higher dry densities thanthe NDM at water contents above 5%.For this testfill the SC tests performed in molecuttings compactedat water contents above 5% are not considered validfor the reasons presented in the following discussion.When the molecuttings were placed at water contentsabove aboutthe compacted surface would exhibit aspongy behavior when one walked across the surface.The degree of sponginess increased as the moistureincreased above the optimum water content.Thesponginess is believed to be caused by water and airpore pressures. The net effect was that as the sandcone hole was excavated the pore pressures at thewalls of the hole were relieved by the walls movinglaterally into the hole until an equilibrium of thepore pressure at the walls of the hole was reached.Thus, by the time the volume of the hole was measureda significant decrease in the volume of the hole hadoccurred but the quantity of soil excavated was fromthe original volume.The result was that the dry soilexcavated was divided by awhich re-sulted in an inaccurately high computed dry density.The SC and NDM test results indicate that the NDM canbe used to determine the in-place dry density and watercontent of molecuttings. The water content bias shouldbe checked periodically to account for changes thatoccur in the molecuttings. Details of a recommendedplacement procedure arepresented in Appendix A.
5.4 Determination of Percent Compaction The field and laboratory data indicated the nuclear densitymeter could be used to determine the in-place dry density afterthe appropriate water content bias had been determined for themolecuttings being tested.The preferred field procedure for determing the percent com-paction of compacted soil is as follows:1.Gbtain a one-point sample of the soil before compaction.2.Perform the' one-point compaction test in the lab anddetermine the maximum dry density from a family ofcurves.3. Perform the in-place dry density of the compacted liftusing the nuclear density meter at or near thelocation of where the one-point sample was taken.This procedure can be used for the molecuttings if at leastthree nuclear density meter determinations of the in-place drydensity are made. The average of the three tests should be usedto represent the in-place density for computation of the percentcompaction. The above procedure will reduce the effect that minorin the character of the molecuttings will have on thein-place dry density determination.The use of a standard laboratory compaction test or one whichwas slightly modified was considered the best method of deter-mining the maximum dry density of the molecuttings.The ModifiedAASHG Compaction Test, ASTM D1557, permits the use of minusmaterial to be compacted in 6-in. molds.Grain-size analysesperformed on molecuttings indicate that nearly 50% of the sampleis retained on thesieve, and, as a result, the materialpassing thesieve would behave much differently than thetotal sample during compaction. A sample of the molecuttings thatwould represent the compaction behavior of the material was con-sidered possible if the amount of coarse material removed waslimited to about 20% by weight of the total sample.This couldgenerally be achieved by removing material retained on thesieve.For the test fill the laboratory compaction used was ASTMD1557, Method C, except the plusmaterial was removed.Because this compaction test, as modified above, was used for thetest fill and gave reasonable results its use is recommended forperforming laboratory compaction tests on the molecuttings.
5.5 Water Content Control The laboratory compaction curves for compaction tests per-formed on samples of molecuttings show a sharp peak in dry densityat the optimum water content, Fig. 6.The dry density drops asthe water increases or decreases from the optimum value.Thelaboratory data show that small variations in water content sig-nificantly affect the degree of compaction that can be achievedin the molecuttings. This behavior was also observed duringplacement and compaction of the molecuttings in the test fills.In the test fill where placement of the molecuttings was con-trolled, the required percent compaction generally could only beachieved by controlling the water content, by either wetting ordrying, of the molecuttings.The most efficient compaction of themolecuttings was when the water content was from about 4 to 6%.Therefore, the water content of the molecuttings should notdiffer from optimum by more than +for most efficienttion.
TABLES TABLEOF FIELD DENSITY TESTS.GRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNo.SampleNo.PercentND-1One-point120.9ThiscolumnND-2samplesnot123.7doesnotap-ND-3obtained121.1plyforcompac-SC-1118.1tiontestper-formedusing2SC-111.19.7120.9123.0115.0ASTM93.5ND-24.810.0116.8120.5117.1Method D97.2SC-39.49.0120.1123.0120.397.88.19.2117.9122.0119.5N.A.13.0122.31 2 2 . 3119.23ND-1One-point123.0SC-2samplesnot126.0ND-3obtained121.4122.5N.A.I5.2I115.5122.1121.548.54.9117.8125.5119.194.98.54.9117.8125.5120.596.05.07.4119.1124.0124.1100.05.0.7.4119.1124.0118.895.8ND-55.8I7.0121.5126.0119.094.4NOTES:One-point compaction sample performed by Pittsburgh Testing Labs.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLEOF FIELD DENSITY TESTSGRAVELLY SAND TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2NO.SampleNo.One-PointLaboratoryMaximumDry DensityIn-PlaceDrDensitypcfPercentCompactionPercentMaterialWaterContent%DensityForMaterial4.89.7124.5125.0125.5100.44.89.7124.5125.0123.899.05.810.3123.1124.0120.997.513.09.3126.4127.0124.998.013.09.3126.4127.0121.395.53.910.0122.3123.2117.895.613.28.4126.0127.0118.793.513.28.4126.0127.0125.799.09.17.6123.3126.5123.097.29.17.6123.3126.5126.699.75.96.8120.5126.5122.596.85.9120.5126.5123.897.910.77.8121.0124.8121.697.410.77.8121.0124.8123.298.711.37.6121.5125.8121.996.9ND-lOne-point119.6SC-2samplesnot118.9ND-3obtained120.2SC-4118.8IN.A.13.8117.9120.9116.2.NOTES:(1) One-point compaction sample performed by Fittsburgh Testing Lab.One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.(3) Percent compaction computed using maximum dry density determined by Pittsburgh Testing Lab.Geo technical Engineers Inc.Project 76301July 12, 1979 PLACEMENT)FILLTABLEOF FIELD DENSITY TESTSQUARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 2LiftNO.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density, pcfPercent%PercentMaterialWaterContento0DryDensityTotalCorrectedForMaterial1ND-12One-pointN.A.145.5N.A.N.A.ND-13samplesnotN.A.144.0N.A.N.A.ND-14obtainedN.A.142.6N.A.N.A.ND-15N.A.146.9144.5N.A.2ND-810.85.1145.4151.0150.0146.997.324.95.1146.0151.5149.5140.993.0(1)7.3.7153.0161.5152.4150.5158.498.43ND-1011.44.6145.9152.0143.1139.091.4ND-1110.4.14.4144152.5151.8145.5152.4.150.7142.8149.898.293.999.24ND-l7.35.0151.2154.0149.4147.495.78.24.6148.3154.0148.3145.994.76.84.3144.9142.792.6.149.797.2NOTES:One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.Project 76301July 12, 1979 MOLECUTTINGS (CONTROLLED PLACEMENT) TEST FILLQUARTZITE MOLECUTTINGS STUDYTABLEOF FIELD DENSITY TESTSSTATIONPage 2 of 2LiftNo.SampleNo.One-PoirMaximumDensityIn-PlaceDensity,MaterialWaterContent%DensityCorrectedForMaterial5ND-85.64.9148.7155.0150.6149.17.74.1146.5155.0148.0145.714.54.7146.0149.4145.0.162.3160.66ND-416.94.0146.0155.0152.6146.0ND-57.84.5147.9153.0150.2148.17.54.2148.3154.0152.3150.4148.3154.07ND-412.54.9145.21 5 1 . 0147.1143.1ND-512.25.0147.5152.0149.5145.9ND-610.44.6146.3152.0147.6144.48ND-lOne-point146.0N.A.ND-2samplesnot146.5N.A.ND-3obtained146.1N.A.PercentCompaction96.294.094.895.596.897.794.896.095.0N.A.N.A.N.A.NOTES: (1) One one-point compaction sample obtained for sand cone and nuclear density test performedadjacent to each other.Laboratory one-point compaction test results and interpolated maximum dry density are fromadjacent nuclear density meter one-point compaction samples and test results.In-place dry density measured is in error for reasons discussed in the text.Geotechnical Engineers Inc.July 12, TABLE 3OF FIELD DENSITY TESTSMOLECUTTINGSSPECIAL CONTROLS) TEST FILLQUARTZITE MOLECUTTINGS STUDYSTATION 2LiftNo.SampleNo.One-Point CompactionLaboratoryMaximumDryDensityIn-Place Dry Density,PercentCompactionPercentMaterialWaterContent%DensitySampleCorrectedFor +Material1ND-4One-point146.3N.A.ND-5samplesnot142.4N.A.ND-6obtained145.5N.A.ND-7149.1149.1N.A.2ND-412.34.6147.7155.0149.4145.794.0ND-510.65.8149.0152.0145.8144.595.1ND-614.55.5149.6152.0145.8142.393.6SC-712.34.6147.7155.0157.8154.591.03ND-56.06.7147.0151.0143.7141.793.8ND-69.26.2147.8151.0141.9.138.591.74ND-l10.66.5148.8151.1144.7141.193.3ND-215.56.6146.0151.0143.0137.190.85ND-l12.34.9148.9153.0150.9147.596.4ND-212.35.0148.1152.0152.2149.098.0ND-324.84.7147.7153.0140.5129.084.36ND-523.54.3153.3156.0154.2147.794.7ND-68.53.6145.1153.0145.1142.393.0ND-79.45.6153.6155.0143.3140.090.3Geotechnical Engineers Inc.Project 76301July 12, 1979 3OF FIELD DENSITY TESTS.SPECIALTEST FILLQUARTZITE MOLECUTTINGS STUDYSTATIONPage 2 of 2CompactionLaboratoryMaximumDryDensityIIn-Place Dry Density, pcfPercentCompaction%WaterContentDryDensityCorrectedForMaterial78ND-7ND-8ND-9ND-1ND-2ND-35.14.07.5One-pointsamplesnotobtained3.13.43.9141.2140.1143.6149.0148.0151.0140.0139.2148.8144.4125.0144.3138.1137.7146.6N.A.N.A.N.A.92.793.097.1N.A.N.A.N.A.Geotcchnical Engineers Inc.Project 76301July 12, 1979 4OF FIELD DENSITY TESTS STRATIFIED MOLECUTTINGS AND GRAVELLY SAND TEST FILLQLJARTZITE MOLECUTTINGS STUDYSTATIONPage 1 of 1LiftNo.SampleNo.One-PairnLaboratoryMaximumDryDensityDensity, pcfPercentPercent+Material%WaterContentDryDensityTOY-11CorrectedForMaterial3ND-715.05.7149.3153.0148.8144.194.2ND-812.26.0148.8152.0145.9141.893.35.6118.3125.0114.3N.A.91.4ND-42.7122.2124.0108.1N.A.87.2ND-53.0115.1123.0108.2N.A.88.0ND-64.9116.9124.5N.A.88.85ND-410.44.3145.7151.0151.3148.5ND-516.33.8144.8153.0138.1130.8N.A.N.A.123.31.27.5123.8N.A.97.17.2123.3127.5121.1N.A.95.0ND-36.8118.8124.5119.3N.A.95.8ND-48.3120.3124.0119.6N.A.96.57ND-104.82.7137.5148.0140.2138.493.58ND-4Onepoint147.3N.A.N.A.ND-5samplesnotobtained140.8N.A.N.A.NOTES :construction or Lift.(2)Values represent percentmaterial.(3)Nuclear density probe may have penetrated gravelly sand layer below.(4) One one-point compaction sample obtained for SC-1 and ND-2.Geotechnical Engineers Inc.Project 76301July 12, 1979 TABLE 5SUMMARY OF PLATE LOAD TESTS RESULTSQUARTZITE MOLECUTTINGS STUDYSTATIONLoadNo.SoilAtTestSoilModulus,psiAveragePercentCompaction1R e m a r k sVirginReload1GravellySand97.12Mole92.6(NoSpecialControl)3StratifiedAve. PercentMoleCuttingsandGravellyCompaction93.7Sand4Mole95.3(ControlledPlacement)5MoleCuttings(NoSpecialPerformed13daysafterControl)PLT-2Geotechnical Engineers Inc.Project 76301July 11, 1979 FIGURES PLAN VIEWTEST FILLSic ServiceofProjectStudyMolecuttingsPLT-3GravellycuttingsSandStratified Mole-cuttings andGravelly Sand(ControlledPlacement)LT-5PLT-4PLT-1PLT-2cuttings(No SpecialNot To Scale PROFILE OF GRAVELLY SANDTEST FILLSteel PlateLift 7 Ave.Comp. = 97.5Lift 6 Ave.Comp. = 97.0Lift 5 Ave.Comp. = 98.1. Lift 2Ave.% Comp. = 97.4Lift 1 Ave.Corns. = 99.0Lift 4 Ave.= 96.2Lift 3 Ave. % Comp. = 100.6Scale:= 2.5'1. One-point compaction samples not obtained.Average percentcompaction is based on maximum dry density provided by PTL.PROFILE OF MOLECUTTINGS(CONTROLLED PLACEMENT) TEST FILLSteel PlateAve.Comp. = 95.3Lift 6 Ave. %= 96.7Lift 5 Ave.Comp. = 95.0Lift 4 Ave. % Comp. = 95.1Lift 3 Ave.= 95.7Lift 2 Ave.96.2Lift 1 Ave.Comp. = N. A.Scale:= 2.5'Molecuttings l -PROFILE OF TEST_ FILLSProject 7630111, PROFILE OF MOLECUTTINGS(NO SPECIAL CONTROLS) TEST FILLLift 1 Ave.Comp. = N.A.Scale:= 2.5'PROFILE OF STRATIFIED MOLECUTTINGSAND GRAVELLY SAND TEST FILLServiceofIMolecuttingsIPROFILE OFFILLSStudyProject11, 19g .Steel Plate (PLT-2and 5)Lift 8 Ave.=Lift 7 Ave.= 94.3Lift 6 Ave.Comp. = 92.7Lift 5 Ave.Comp. = 92.9Lift 4 Ave.Comp. = 92.1Lift 3 Ave. % Comp. = 92.8Lift 2 Ave.Comp. = 94.7.Steel Plate (PLT-3)Lift 8 Ave. % Comp. = N.A.Lift 1 Ave.= N.A.Scale:2.5' U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDRCMETER6432IofLabs.Pro-iIGrain-size analyses per 'formed,..COBBLESCOARSEIFINECOARSEMEDIUMIFINEWINCHESTERMASSACHUSETTS3 4 6GRAIN SIZE MILLIMETERSSIZEQuartziteMolecuttingsGRAVELLY SANDStudyITEST FILLIIi11, 1979 NOTE: 1. Compaction test performed inwithC,the plusmaterial. was discarded and no limitationplaced on the percent retained on thePublic Service Company ofNewhireQuartzite MolecuttingsStudyProject 76301. COMPACTION CURVESMolccuttingsJuly 12, 1979Molecuttings- V W - -ControlledMolecuttings(No Special Controls)(Controlled Placement)Lift 4s = 100%-Gave = 2.83 (De152..02468IOWater Content, U.S. STANDARD SIEVE OPENING IN INCHESU.S. STANDARD SIEVE NUMBERSHYDROMETERGRAIN SIZE MILLIMETERSCOBBLESSANDFINEGRAIN SIZESAMPLES OFMOLECUTTINGSQuartziteMolecuttingsstudyICOARSE FINE COARSEMEDIUMWINCHESTER . MASSACHUSETTSanalyses performedusing successive elutriation.MOLECDTTINGSMOLECUTTINGSLIFT 2LIFT 4I -I - -500100505I0.561(No Special Controls4 32I820 30 40 50 70200MOLECUTTINGS(Controlled Placement)(ControlledPlacement)0.050.001
.MOGravelly Sand302520151050PERCENT COMPACTIONVERSUS9092349698100Percent ofof Modified AASHO, %NOTES: 1. Modulus of elasticity computed using theory of elasticityfor semi-infinite, isotropic soil.2.Modulus of elasticity value plotted is minimum value fromvirgin loading curve.3.Percent compaction is the average percent compaction ofthe first three layers of soil under the plate.4.Percent compaction the average percent compaction of twolayers of molecuttings and one layer of gravelly sand.5.Range in percent compaction is estimated.See discussion in text.Public Service Company ofQuartziteMolecuttingsStudy76301 4.06.08.014.0Nuclear Density Meter Determined In-Place Water Content,WATER CONTENTSAND CONE VSDENSITY METERGRAVELLY SANDJu98 . 06 . 0Estimated Line ofGravelly SandBest Fit Gravelly Sandr11114116118122124126Density Meter Determined In-Place Dry Density, pcfNOTES: 1. In-place dry density includes plusmaterial. .2.In-place dry density based on 8-in. deep nuclear test.Densitieshave been corrected for water content bias according to plot ofversusnuclear for gravelly sand:conedevice3.Cone and Nuclear Density Meter determinations were performedto each other (about 6-12 in. apart).SAND CONE VS NUCLEAR DENSITY METER DET.DRY DENSITYGRAVELLY SAND10.-.--.----PublicCompany of.Elcwi L-CIIIIIQuartzitestudyProject 76301 Nuclear Density Meter DeterminedWater Content,(after bias was corrected)8 . 07 . 06 . 0Molecuttings3.04.05.06.07.08.0NOTES: 1. In-place water content is baseddeep nuclear test.
135145150155160Nuclear Density Meter Determined In-Place DryDensity,NOTES: 1. In-place dry density is uncorrected for the plusmater2..except where noted.3.Water content of Sand Cone was greater than 5.0%.4.In-place density is based on 4-in. deep nuclear test.MolecuttingsPublic Service Company ofSAND CONE VS NUCLEARiSITY METER DET. IN-PLACEDRY DENSITYMOLECUTTINGSI.QuartziteMolccuttingsStudyProject 7630111, APPENDIX ASAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35in.75-1032-O22-o10-O2.The uniformity coefficient,should be notless than 5.B.PLACEMENT1.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 95% of maximum dry densityas determined by ASTMwith exceptions fortesting noted in Section C.2.2.The water content of the molecuttings should be atoptimum1% during placement. The water contentduringof quartzite molecuttings shouldbe stockpiled or otherwise treated to reduce thewater content to less than 6%.If the water contentis less thanthe addition of water during com-paction will be necessary if satisfactory compactionis to be achieved.3.Molecuttings should not be placed in direct contactwith pipes, culverts, or other structures sensitiveto abrasion and/or high point loads.4.The pore fluid of the molecuttings is brackish and,as a result, the resistivity of the muck is likelyto be below the minimum limit of 10,000United Engineers is to develop recommendations forplacement of the molecuttings in areas when highresistivity of backfill material is required.
C.TESTING AND FIELD CONTROLDue to anticipated variations in rock type thecuttings should be monitored daily by determining thegrain-size distribution, water content, and rock typefor at least one typical sample.The grain-sizeanalysis should be performed by using a wet sievingtechnique and every tenth test should be performedby using the elutriation method, without pre-dryingof the sample. The frequency of testing may be re-duced in time after those testing become familiar withthe material and thus capable of judging when thematerial is or is not acceptable.a.If the percent passing thesieve materialis greater thanthe material should not beused.b.If the water content is greater than 1% aboveoptimum, the molecuttings should be stockpiledor treated to reduce the water content to optimum.2.A family of at least three compaction curves should bcdeveloped using ASTM D1557, Method C, except that theminusmaterial shall be used. Each compactioncurve should be accompanied by a grain-size analysis.Additional compaction curves should be performed onceevery 7,500 yards or earlier if visual changes in themolecuttings grain size is observed.3.A bag sample of the molecuttings should be obtainedafter the loose lift has been placed and before com-paction begins. The sample should be large enough toperform a laboratory one-point compaction test and tomeasure the percent material retained on the l&inchsieve.4.Separate the plusmaterial and calculate itspercentage by weight of the entire sample.5.A one-pointtest should be'performed on thebag sample of molecuttings in accordance with ASTMD1557, Method C, except that the minussievematerial shall be used.The maximum dry density for this sample, yd , is determined by plotting thepoint dry on the family of curves and inter-polating the maximum dry density for the minusmaterial.6.The in-place dry density should be determined by per-forming at least three nuclear density meter tests.The average dry density should be used to computethe percent compaction.This method should reduce theeffects of sharp variations in the molecuttings on thein-place dry density determinations.a. The water content bias for the nuclear densitymeter should be corrected for use in molecuttings.The water content bias should be checked weekly.7.The percent compaction is determined by dividing thecorrected in-place dry density by the laboratory maxi-mum dry density as determined in 6. above. A formulato compute the corrected in-place dry density, tocorrect for the quantity of plusmaterial, ispresented below. = 1-Rwhere= corrected in-place dry density for theminussieve material= average in-place dry density determinedby using nuclear density meter= unit weight of waterG = specific gravity of molecuttingsR = percent, by weight of the total sampleretained on thesieveThe percent compaction is computed as follows:Percent Compaction P(%) =x 100.= Maximum dry density of minusmaterialdetermined in Step 5. from the family ofcurves and the one-point compaction.YND NONSAFETY-RELATED STRUCTURAL FILLA.MATERIAL1.Gradation for molecuttings should meet the followingcriteria:100100-70100-35100-1775-10No. 2022-o10-O2.The uniformity coefficientnot be lessthan 5.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 93 of maximum dry density asdetermined by ASTM D1557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Molecuttings can be sandwiched between presently ac-cepted gravelly sand structural fill. Whencuttings and gravelly sand are alternated in the back-fill, the following limits are recommended.a.Molecuttings should be placed in 8-in.-thick looselifts and compacted to 93maximum dry densityas determined by ASTMb.Gravelly sand should be placed in accordance withthe present specification for structural fill (i.e.,8-in. loose lifts compacted to 95% of ASTM3. The water content of theshould beoptimum1% during placement if no gravelly sand layersare present. When the molecuttings and gravelly sandare placed in alternating layers, the water content ofthe molecuttings may be permitted to be as high as 2%above optimum.If the water content of the molecuttingsexceeds the suggested limits of water content, thecuttings should be stockpiled or otherwise treated toalter the water content.If the water content is low,say 2 tothe addition of water during compactionmay be necessary to achieve satisfactory compaction.
RANDOM FILLA.MATERIALThe molecuttings to be used asFill should complywith the present specification as described in Specification No.9763-8-4, Section 3.2.2 dated September 27, 1974.B.PLACEMENT1.Molecuttings should be placed inlooselifts and compacted to 90 of maximum dry density asdetermined by ASTM Dl557 with exceptions noted inSection C.2 for Safety-Related Structural Fill.2.Although limits on the water content of thecuttings are not necessary, the most efficient com-paction will occur at optimum water content1%.C.TESTING AND FIELD CONTROLTesting and field control for use of molecuttings as Ran-dom Fill should be the same as outlined for Safety-Related areaswith the following exceptions:The gradation of the molecuttings should comply withpresent specifications for Random Fill.No limit on the water content of the molecuttings isrecommended.The maximum permissible water contentin the field will be dictated by the ability toachieve the required percent compaction.
APPENDIX
APPENDIX BPLATE LOAD TESTB-l PurposeThe plate load tests were performed to determine the de-formation characteristics of gravelly sand and molecuttings.The results of the plate load tests provided the basis forcomparison of the two materials and to determine the effectthat percent compaction has on their deformation characteristics.. B-2 ProcedureFor each test a 24-in. -diameter hole was excavated to adepth of 12 in., except for test PLT-3 which was 6 in. deep.An -diameter, thick steel plate was placed on athin layer of liquid hydrous stone which was placed directlyon the bottom surface of the test hole. Additionalsteel platesandin diameter were placed in apyramid arrangement on top of theplate.After the hydrous stone and plates were in place, theplate was loaded by a hydraulic jack reacting against the under-side of a loaded, flat-bed trailer, as illustrated in Fig. B-l.The loads were measured using a calibrate pressure gage.Deformations of the plate were measured using three dialindicators attached to a reference beam as illustrated in Fig.B-l. The dial indicators were graduated to mm. The ref-erence beam supports were separated from the center the plateby about 72 in., which was a sufficient distance for deflectionsunder the supports to be negligible during loading of the plate.The loading sequence for each test was as follows:1.Applied load to develop contact stress of 4 tonsper square foot (tsf) in four equal increments.2.Unload to zero load in two equal increments.3.Repeat load-unload cycle to 4 tsf.4.Load to develop contact stress of 12 tsf in sixequal increments.
EDS-2-5.Unload to zero load in three equal increments.6.Repeat load-unload cycle to 12 tsf two more times.Each loading or unloading increment was held constantuntil the rate of deformation of the plate was less than.001The air temperature when the plate load tests were per-formed was aboutF.B-3 ResultsThe load versus displacement curves for the five plate loadtests are illustrated in Figs. B-2 through B-6.The slope ofthe virgin load curve was generally straight except for testPLT-2 and PLT-3 where slight curvature was observed.The slopeof the reload curves were much flatter than the virgin curveand the slopes of the repeated reload-unload cycles were parallelas would be expected.Values of Young's Modulus, E, were calculated from the re-sults of the plate load tests using elastic theory.The solutionfor the settlement of a loaded, rigid circular plate on anelastic half space is as follows:where s = settlementq = average stress on the plateP = load on the plateD = diameter of the plate= Poisson's ratioI = influence factor =E = Young's ModulusAssuming a value v = 0.3 and rearranging to compute E, yields:The modulus calculated is the average modulus within the zoneof significant stress which for anplate would extend between18 to 36 inches beneath the plate.The moduli calculated using this method are presented in TableFor each test tangent moduli were calculated using the straightsegments of the load and reload curves.
PLATETEST EQUIPMENTWINCHESTER .Project 76301Julv 12, 1979PublicofNew HampshireReaction Structure (Loaded Flat-bed Trailer)\ LiquidHydrousStoneBearing PlatesDial IndicatorBeamRefBeamSupportof Test FillNOTE: 1.Depth for PLT-3 was about 6-in.Schematic Illustration of Plate Load Test Equipment--(Not ToDialSteel Bearing PlateDial"Ear" Welded To Bearing PlateDial indicatorsandmonitored displacement of "ears" attachedto circumference of bearing plate.Plan---Locations of Dial Indicators(Not ToStudy 6 . 07 . 08 . 002.06.08.0. 10.012.0Vertical Stress. tsfDate Performed:June 7, 1979By:Fisher/R. GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONPLATE LOAD TESTGRAVELLY SAND...11I 802.04.06.010.012.0icof.QuartziteProject 76301StudyPLATETEST PLT-211.Vertical Stress, tsfDate Performed:June 14, 1979By:GardnerPlate Diameter:VERTICAL STRESS VSDEFORMATIONCON.)
41.2.3.04.06.08.0Vertical Stress, tsfDate Performed:June1979By: W. Fisher/R. GardnerPlate Diameter:Company of10.012.0VERTICALVSMolecuttingsStudyPLATE LOAD TEST PLT-3ST.GR.76301i 04 . c04.06.08.010.012.cVertical Stress, tsfDate Performed:June 18, 1979By:Fisher/R.GardnerPlate Diameter:MolecuttingsPLATE LOAD TEST PLT-4. . . . --a.---1.02.03.0DEFORMATIONStudy 02.04.06.08.010.012.0..Vertical Stress, tsfDate Performed:June1979By:FisherPlate Diameter:- -.STRESS VSDEFORMATIONPLATE LOAD TEST PLT-5MOLECUTTINGS -(NO SP. CON.-July 11,g .1 . 0.2 . 04 . 05 . 06.07.0IIIIIQuartziteStudy TABLESUMMARY OF FIELD DENSITY TESTSPageLiftSampleOne-PointCompactionLaboratoryIn-Place Dry Density, pcfNo.No.PercentWaterMaximumTotalCorrectedCompactionMaterialContentDensityDry DensitySampleForMaterialoa00%
UPDATED FSARAPPENDIX 20GEOTECHNICAL REPORT DISCUSSION OF DERIVATION OFCOEFFICIENTS OFREACTIONThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
March 22, 1978Project 77386File No. 2.01017 MAIN STREET. WINCHESTER. MASSACHUSETTSMr. JohnPublic Service Co. of New Hampshire1000 Elm Street 11th Floor.Manchester, NH 03105
Subject:
Discussion of Derivationof Coefficients ofReaction
Dear Mr.In the following we describe some techniques that we havedeveloped to convert the moduli obtained from triaxial tests tomoduli ofreaction for various loading conditions. Wepresent this information to complement various telephone con-versations with D. Pate1 ofComputation of Coefficients ofReactionThe coefficient ofreaction,
represents soildeformation, due to pressure acting along a boundary surface,as if the soil were composed of independent springs, each repre-senting a unit of area with a spring constantThe springconstant is defined as a pressure divided by a displacement.Such a representation is convenient for analytical purposes butneglects the influence of adjacent loaded surface areas on thedisplacement of any given point on the boundary surface.Thus,the coefficient ofreaction is not a unique number foran elastic material but is a function of the size of the loadedarea, the pressure distribution, and the geometry ofmaterial.For a soil, the modulus ofreaction is also dependent onthe method or sequence of loading, i.e., the stress path.On the basis of the theory of elasticity, wecomputedcoefficients ofreaction for the structural backfill andthe sand cement for three geometries of loading using the modulusof elasticity and Poisson's ratio data obtained in the triaxialtest results. The geometries of loading studied are illustratedin Figs. 1 through 9 and are as follows:
Mr. JohnMarch 22, 19701.Circular or square footing subjected to vertical load.2.Pressure inside a cylindrical cavity in the soil massassuming a plane strain condition.This istive, for example, for the loading produced by thermalexpansion of the cross section of a buried pipe.3.Pressure inside a cylindrical cavity with simultaneousapplication of a vertical surcharge, p, and a horizon-tal pressure,This loading is an approximate re-presentation of the placement of fill over a buriedwhich deforms to produce an increased lateralstress around the pipe.A plane strain condition was.assumed.The modulus of elasticity and Poisson's ratio used in the compu-tations are strain dependent and were selected for the average strainin the region of the soil mass that contributes most to the displace-ments, namely, within a distance of one diameter from the pipe and onefooting width below the footing base. These strains were correlatedwith the displacements which, in turn, were expressed in terms offooting settlement divided by6/B, or in terms of thediameter strain of the pipe,In Figs. 1 through 9, the values ofthe coefficient ofreaction are plotted as a function of (T/Borand confining pressure. Confining pressure is to be taken asthe effective overburden pressure computed at the elevations shown inthe figures. An exception to the above procedure is that for the sur-charge type loading, a constant Poisson's ratio of 0.3 was used.The elastic modulus E and Poisson's ratio v used as a basis forthe coefficient of reaction computations were obtained fromtriaxial compression tests in which the minor principal stresses werekept constant and the major principal stress was increased monotoni-cally until the specimen failed. Such a stress path would be sufficientto determine E and v for an elastic material.However, soil is notelastic and E and v are dependent on the stress path or stress history.In particular, higher values of E would be obtained for repeated orcyclic loading. For the static load conditions, we feel that the valuesofreaction presented are reasonable estimates for the in-situloading conditions. As shown in the next section, the values comparewell with values given in published literature.We recommend, however,that when these values are used, sensitivity analyses should be made toassure that the designs are safe for a range 25% above and below thegiven values.Comparison With Published Coefficients ofReactionThe coefficients ofreaction obtained from thetestswere compared with data presented by K. Terzaghi in the paper entitled PrincipalGC/SJP:msEncl.ccR.YAECD.A. Desai,D. Patel,Mr. JohnMarch 22, 1978"Evaluation of Coefficients ofReactionGeotechnique,vol. 5, 1955, pp. 297-326.For shallow footings the vertical coefficient ofre-action for a one square foot plate, is estimated by Terzaghito range between 300 and 1,000 ton/cu ft for dense sands, i.e., arange for x B of 4,000 to 14,000 psi. These values are intendedfor shallow footings,a typical depth of embedment, Dof 4ft, and for a width, B, of one foot.Thus, they areof confining pressures equivalent to a depth of 4.5 ft or about 4 psi.The coefficient of horizontalreaction is given byTerzaghi for a 1 sq ft vertical area at a given depth, and it isassumed to be proportional to the effective stress at that depth.For example, for dense sands at a confining pressure of 10 psi, arange ofof 7,000 to 14,000 psi is indicated..Thedata for structural backfill, for strains of aboutFigs. 1, 2, 4 and 5, agree with Terzaghi's data.No specific infor-mation on strain level is given by Terzaghi for his data, but heindicates that the data are applicable to a factor of safety againstbearing capacity failure that is larger than two.It is also implicitthat the factor of safety would not be much more than 2.Perhaps itlies in the range of 2 to 4.For such factors of safety, the resultsof plate load tests on sands (1 sq ft plate) would indicate typicalsettlements of 0.1 in. to 0.3 in., which would be equivalent to avertical strain on the order of 1% in the soil adjacent to the plate.Thus, the data for the structural backfill obtained from the triaxialtests correspond to coefficients ofreaction within therange given by Terzaghi.Sincerely yours,GEOTECHNICAL ENGINEERS INC.Steve J. PoulosPrincipal FIGURES ReactionGeotechnical Engineers Inc.Winchester,MassachusettsProject 77386Public Service Company ofNew Hampshire=March 13, 3.978Fig. 1SETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt462347Sand and Sand-CementBackfillPRESSURE ONBACKFILL90% COMPACTION ReactionSETTLEMENTEFFECTIVE VERTICALSTRESS AT DEPTHt B/2)..4IO'986544567 8 910234568sProject,.77386FOOTING PRESSURE ONSTRUCTURAL BACKFILL95% COMPACTIONMarch 13, 1978Fig. 2Public Service Company ofNew HampshireGeotechnicalInc.Winchester, M a s s a c h u s e t tSand and Sand-CementBackf ill 96SmSETTLEMENTk9765= EFFECTIVE VERTICASTRESS AT DEPTH445679102346789100Public Service Company ofReactionFOOTING PRESSURE ONNew HampshireSand and Sand-CementSAND-CEMENTBackf illBACKFILLEngineers Inc. ,Winchester,MassachusettsProject 77386March 13, 1978Fig.
ReactionSand and Sand-CementBackf illEngineers IncWinchester, MassachusettsProject 77386Public Service Company ofNew HampshireMarch 13, 1978Fig. 4INTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILLCOMPACTIONIO'9765976541456 7 8 91023456 7 65489467 8 9102346ReactionProject 77386March 13, 1978Fia. 5Sand and Sand-CementBackf illINTERNAL PRESSUREPIPE BURIED INSTRUCTURAL BACKFILL95% COMPACTIONPublic Servide Company ofNew HampshireGeotechnical Engineers Inc.Winchester,MassachusettsEFFECTIVE VERTICALSTRESS AT DEPTH Z2U=I IO986987463456 7 8 91023456 7 8Public Service Company ofNewGeotechnical Engineers Inc.Winchester,MassachusettsReactionSand and Sand-CementBackfillProject 77386March 13, 1978Fig. 6= EFFECTIVE VERTICALSTRESS AT DEPTHSAND-CEMENT BACKFILLINTERNAL PRESSUREPIPE BURIED INDISPLACEMENT ReactionDISPLACEMENT=98765= EFFECTIVE VERTICALSTRESS AT DEPTH4452346 7 8 9 0 0SURCHARGE PRESSURE ONPIPE IN STRUCTURALBACKFILLCOMPACTIONMarch 13, 1978Fig. 7Project 77386Sand and Sand-CementBackf illPublic Service Company ofGeotechnical Engineers Inc.Winchester, MassachusettsNew Hampshire 4567 8 910234564ReactionSand and Sand-CementBackf illProject 77386BACKFILL'95% COMPACTIONMarch 13, 1978Fig. 8ON PIPE IN STRUCTURALSURCHARGE PRESSUREInc.DISPLACEMENT= EFFECTIVE VERTICALSTRESS AT DEPTH ZPublic Service Company ofNew HampshireWinchester, Massachusetts UPDATED FSARAPPENDIX 2PSTATION CONTAINMENT AIRCRAFT IMPACT ANALYSISThe information contained in this appendix was not revised, but has beenextracted from the original FSAR and is provided for historical information.
FSARAPPENDIX 2P STATION CONTAINMENTAIRCRAFT IMPACT ANALYSISPrepared byUNITED ENGINEERSCONSTRUCTORS INC.OCTOBER 1975PUBLIC SERVICE COMPANY OF NEW HAMPSHIRESEABROOK, NEWHAMPSHIRE CONTENTSABSTRACTl-ll-ll-12l-14l-15FSARCONTENTS1.0 Structural Analysis ofStation Containmentfor Aircraft Impact l-l1.1Introduction ------------------------------1.2Forcing Function for Impacting Aircraft1.3Behavior of Containment -------1.4Response of the Enclosure Building -----1.5Shear Capability of the Containment ----1.6Requirements to Prevent Perforation ----1.7Conclusions1.8References for Section2.0 Fire Hazard Analysis ofStation 2-l2.1CombustibleVaporProduction 2-22.2FireAnalysis2-22.3Evaluation of Various Safety Related Areas 2-42.4Hazards from Smaller Aircrafti 2-62.5Conclusion2-72.6References for Section2-7l-18 SBFSARABSTRACTResults are presented which verify the adequacy of thecontainment to resist the impact of an FB-111 type aircraft.Includedis a description of the dynamic forcing function, the elastic-dynamicanalysis, the elastic-plastic analysis, an estimate of reinforcementand liner strain and a verification of the punching shear capabilityof the containment.It is shown that there existsmechanism by which spilledfuel from the impacting aircraft can access theThe ensuingfire is, therefore, postulated to start in thevicinityexternal toenclosure and it is demonstrated that these externalfires do not, in any way, inhibit or handicap the safe shutdown cap-ability of the plant following the postulated crash.It is concluded, that under the aircraft impact, the containmentstructure is able to withstand postulated impact and that the consequencesof the aforementioned fire hazard is mitigated by the inherent designfeatures ofStation.
1.0 STRUCTURAL ANALYSIS OFSTATION+2l-ldxFSARAIRCRAFT IMPACT1.1 IntroductionTheStation containment has been analyzed for the effects ofa-postulated impact by an FB-111 type aircraft with a speed atimpact of 200 mph.Based on the analyses performed;-theof the containment to withstand the postulated impact is verified.TheStation containment and enclosure building is describedin Section 3.8.1 of thePSAR. The FB-111 aircraft, the missilein the postulated73.5 feet long, has a wingspanoosition) of 70.0 feet and weighs 81.800 Dounds (See Reference 1).In order to perform the analyses,a force-time relationship isdeveloped from the mechanical properties of the impacting aircraft.An elastic dynamic analysis indicates that an elastic-plasticdynamic analysis is required to predict theresponse of thestructure.From this analysis of the structure,is madeof the strains experienced by the reinforcing bars and liner.Subsequently, an analysis is performed to verify the adequacy of thecontainment against punching shear and penetration.1.2 FORCING FUNCTION FOR IMPACTING AIRCRAFTThe time variation of the load on a rigid surface due to an impactingaircraft may be developed using the momentum principle.The governingequations which are used to determine thevariation of the forceexperienced by the target are (Reference 2):
FSARwhereR(t) is the force acting on the target (positive for compression),is the extent of crushing at any time t as measured from theleading edge of nose of the missile,is the load required to crush the cross section of the missileat any distance n from the nose,(positive for compression)is the mass density per unit length of the missile as a functionof the distance from the nose.These equations are used to determine the two unknowns, the crushinglength,and the reaction, R(t), as functions of time.Theinformation required to determine these variables consists of theinitial impact velocity, weight or mass distribution and crushingload distribution of the aircraft.The first equation is integrated numerically to obtain the velocitytime history. The reaction force is then determined from the secondequation.Figureshows three views of the FB-111 aircraft. Figurethe one dimensional idealized model of the same aircraft. Figure 2bdescribes the weight distribution for an FB-111 with a total weightof 81,800 pounds.The sketch and the weight distribution are obtainedfrom Reference 1.The particular configuration used is essentiallythe same as that summarized on P. 1.3.3 of Reference 1 with the wingstores and wing useful load removed.This configuration is consistenttheof the FB-111 at Pease AFB. The value of 81,800 pounds is thel-2 FSARweight before the airplane has warmed up and taken off.flights the aircraft would fly a mission and return to Pease AFB withapproximately 10,000 pounds of fuel.On this basis, the landingweight would be approximately 59,000 pounds.For those missionswhen the aircraft is flown with wing tanks the maximum take-offweight ispounds. The FB-lllis not allowed to land withfuel in these wing tanks; therefore in all cases the maximum landingweight is 81,800 pounds.Thus, the 81,800 lbs weight of the FB-111 used in the impact analysiswas the fully loaded FB-111 without wing tanks.This weight isconservatively large for any configuration of the aircraft flyingout of Pease AFB, but it was used because it represented a maximumupper bound on the weight of the FB-111 in the landing pattern.The exact crushing load distribution foran PB-111 is not available.The crushing load distribution shown onis arrived at byscaling the known values for ais demonstratedin this report that the peak value of the reaction is relativelyinsensitive to reasonable variations ofthe crushing load.Figure 3 shows the reaction-time relationship for the FB-111 strikinga rigid wall at an impact velocity of 200 mph. The peak value of thereaction is 8.2 x pounds. This peak value occurs when the wingstructure is in the process of collapsing.This peak reflects thel-3 PC8.5 x8.2 xpounds7.1 xpoundsFSARmass in the wing structurefuselage in the vicinitythenoted that the cross-sectional area overlargerthe area of fuselagesecondaryof 4.2106 pounds (atthe vicinity of the engines.The determination of the sensitivity of theto the magnitudethe crushing load is investigated bytheforvalues of one-fifth and fivethis crushing load.Theseresults are shown in Figure 4.From Figure 4,peak values of thereactions are:The peak value of the reactionrelativelv insensitive to variationsin' the magnitude of the crushing load, and the scaled value of PCjudged to give accurate results.1.3Behavior of Containment1.3.1 Elastic Dynamic Analysis For the elastic dynamic analysis, the finite element methodwas chosen as the analytical method, and a computer programfor axisymmetric structures subjected to arbitrary static anddynamic loads was used.(See Reference 3 for the basis of themechanics of the program.) Damping was not considered. Thus,the predicted structural response is slightly larger than thatwhich does occur.l-4 FSARTo accomplish the analysis, several assumptions were made.They are as follows:i)Theis fixed at the base of the cylinder.ii)Impact loads are uniformly distributed over the loadingzones.iii)In the axisymmetric analysis (impact at apex of dome), theloading zone is a circle with a radius of 52.77 inches andan area of 8748.3 square inches.iv)In the asymmetric analysis (impact at springline), theloading zone is a square,93.53 inches on a side and8748.3 square inches in area.v)The stiffness of the reinforcing steel is neglected; onlythe gross concrete volume is considered.The modulus ofelasticity was taken as 3.0 xin., Poisson'sratio was taken as 0.15, and the weight density wastaken as 150 pcf.vi)The effect of the enclosure building is neglected. Itcan be shown that the enclosure absorbs approximately 4%of the energy of the impacting aircraft.The containment structure is modeled with axisymmetric conicalshell elements, a plot of this model is shown in Figure 5.Two impact positions, the apex of the dome and the springline,are considered. The impact at the dome is uniformlydistributed over the first seven (7) elements, and the impactat the springline is uniformly distributed over the six (6)elements nearest to the springline.By means of a half-rangecosine series, the load at the springline is confined to al-5 FSAR6.18' arc.(30) terms were used to represent thisFourier series which is shown, normalized to 1.0, in Figure 6.Experience with loadings similar to the loadings here, hasdemonstrated that twenty (20) terms of the series were foundto be too few and ninetyterms were found toresultsvery close to those generated by thirtyterms.Selected maximum results for the axisymmetric and asymmetricanalyses are given in Tablesand l-2, respectively. Thesemoments will cause cracking of the concrete and yielding oftheTherefore, an elastic-plastic dynamic analysis isrequired.1.3.2' Elastic-Plastic Dynamic Analysis The procedure followed for the elastic-plastic analysis ofthe response of the containment under aircraft impact followsthat of(Reference 4). In this procedure, knowing theload-time relationship, the first natural frequency of thatpart of the structure participating in the energy absorption,and the allowable ductility ratio (defined as the ratio of themaximum deflection to the deflection at yield), the ratioof the maximum value of the load-timeto themaximum value of the resistance function can be determined. This1-6 SBFSARcan then be compared with the actual estimated maximum valuesof the load-time relationship and resistance function.The force-time relationship, given in Figure 3 is approximatedby a triangular load-time curve with the same total impulseand peak force.This ideal and the actual force-time relation-ships are compared in Figure 7 .It is assumed that a circularregion of radius "a" will participate in the energy absorption.The natural frequency, associated with this participatingregion, is estimated on the basis of the first naturalfrequency of a flat circular plate of radius "a" clamped atthe edges.The assumption of clamped edges, in that it givesa smaller period for the first natural frequency than in theactual case, is a conservative simplification. This followsbecause, in general the value of the maximum allowable forcingfunction decreases as the first natural period decreases (Ref. 4,p. 78, Figure 2.26).Conversely, ignoring the curvature isnon-conservative in that it gives an estimate*of the periodwhich is larger than the actual case.For small values of theradius "a", the curvature effect is minimal.All calculations are based upon thedome sectionconfiguration.The first natural frequency of a flat circularplate, clamped at the edge is:PX.17whereis therigidity and M is the mass density per unitsurface area (See, for example, Ref. 5).l-7 FSARthethick concrete plate with a Young's modulus ofpsi and a unit weight of 150 pounds per cubic foot,period is:sectioncracked section"a" in feet T15.94 x12.86 xUsing Fig, 2.26 of Reference 4the ratioas afunction of the radius of the participating material of thecontainment,can be determined for various values ofductility ratio.For the purpose of this investigation, two (2) ductilityratios, 3 and 10 are used. For plates and shells, the lowervalue is conservative, the larger value reasonable. Theresults of the calculations are shown in Table l-3 and Figure8.Although the range of Fig. 2.26 of Reference 4 islimited to aof 20, it can be observed that for aductility ratio greater than two and of 20, isgreater than unity. Therefore, the allowable peak force,F, can be than the maximum value of the resistance, Rm.1.3.3 Resistance FunctionIn the vicinity of the impact region, the response of thestructure is assumed to have the characteristics shown inFigureFor values of the force less than Rm, the displacements arelimited in magnitude even though the response may be inelastic.As the load reaches the valuethe deformations are ablel-8For3xthe 2+=FSARto become arbitrarily large, i.e.,the collapse load has beenreached.The collapse load for a concentrated load on acurved shell is not readily accessible.As a conservativeestimate, the collapse load for a flat plate with reinforcementthe same as the dome is used to estimate the collapse loadfor the shell..Expecting the yield line formation shown in Figureobservationsuggests that the clamped boundary condition case should beused. The value of the collapse load, Rm, is then (Referencewhereis the ultimate moment capacity and the notation + andrefers to the outside and inside reinforcement respectively.The ultimate moment capacities and collapse loads of thecontainment are:dome= 643 k-ft. /ft.651 k-ft./ft.springline= 1,235 k-ft./ftM-643 k-ft./ftAt the dome, the collapse load and peak load are approximatelyequal.However, from Figure 8 , the dynamic effect allowsthe structure to withstand loads in excess of the capacity.From Figurethe allowable load is 10% larger than theresistance or collapse load.Therefore,the apex will notl-9 FSARcollapse.Since the maximum load,less than thecapacity of the dome in the springline,collapse willnot occur at the springline.The dome will not collapse, under the applied load.1.3.4 Estimation of Rebar and Liner StrainsWhile plastic analysis techniques are useful for finding collapseloads, they cannot be directly used to find the strains anddisplacements corresponding to collapse loads.However, a procedure making use of the ductility ratio can beused to approximate the maximum strains in the structuresubject to dynamic loading when nonlinear material behavioris encountered.This procedure is described below.A typical load-displacement curve for reinforced concretesection is shown in Figure 10.This curve is linear up to theload causing crackingafter which a straight line ofsomewhat flatter slope is obtained until the loadisreached which causes yielding of the steel.Any increase in load beyondcauses the displacement toincreasedisproportionately.Further increase in load causesextensive displacements to occur,resulting in eventual collapse.This actual behavior of the structure was idealized as shown inFigureand was used for the elastic-plastic dynamic analysispreviously discussed.Thiscurve represents theresistance function of the structure.l-10 Y60 0.002FSARThe ductilityreferred to in the elastic-plasticdynamic analysis represents the ratio of the maximum displacementof the structure to the deflection established as yieldforthe structure.While it is recognized that the ductility ratio is not an exactmeasure of the maximum strain at a particular point of thestructure, it can be used as an approximation because theat yield in the actual structure is very nearly the straincorresponding to yield for the idealized structure.The procedure used herein is based on the peak of the actualforcing function resulting from the-aircraft impact, the durationof loading, theresistance function for the structureand the first natural period of the responding part of thestructure.By using the above known quantities, the correspondingductility ratio for the structure may be determined.For a peak in the forcing function of and ain the resistance function of 8,130 k, the maximum ductility ratiofor all ratios of is Fig. 2-26, Ref. 2).Thus, regardless of the natural period of the responding part ofthe structure, the largest displacement that will occur under theaircraft impact loading is the same as that to yieldfor the idealized structure.The yield strain for the reinforcing steel is SBFSARIf it is assumed that thecorresponding to yieldforthe idealized structure is 50% larger than this (actuallymuchless than this),, then an upper bound for the strain in thereinforcing steel will be:x 1.5 x 0.002 in/in =in/inSince the liner and the tension reinforcing steel are only severalinches apart in a 42" thick containment dome, they will bestrained to nearly the same values.Hence, there will be nopossibility of impairing the leak tight integrity of the liner.1.4 Response of the Enclosure Building During the early stages of the impact process, the enclosure buildingwill deform until it comes into contact with the containment. Theenclosure building must deflect five feet in order to come intocontact with the containment dome.Such a deformation will involvean inelastic response.This inelastic response will involve bothflexure and shear.The 15" thick enclosure building is reinforced withboth ways and both faces.The collapse load is 635k.The allowable shear load will depend upon the shear area over whichthe transverse shear stress acts. This shear area is determined bymultiplying the average shear periphery by the effective depth ofthe shell. The average shear periphery is determined by a contourwhich is at a distance of one-half the effective depth away from thecontour of the contact area (Figure 12 to 21 show theimpact area and shear periphery associated with various locations1-12 FSARalong the aircraft and for the effective depths of the enclosurebuilding (9") and containment (37").The reaction as a function of the cross section being crushed isdetermined from the reaction-time and crushing distance relationshipand is shown in Figure 22.From this information, it is possible to examine the effect of theaircraft impact on the enclosure building as a function of thedistance being crushed.Figure 23 shows the average shear stresson the enclosure as a function of distance being crushed.Forexample, using a shear strength of 4.25the enclosure buildingwill fail by shear when the aircraft is crushing at 7.25 feet.Alsoshown on Figure 23 is the reaction as a function of the distance beingcrushed.For a collapse load ofthe enclosure building willcollapse when the aircraft is crushing at 9.75 feet.It wouldappear that, usingas a shear strength,the enclosurewould fail by shear before collapse, however, the two eventswould occur at a time difference of 0.0086 sec. Any increase inactual shear strength abovewould increase the possibilityofand collapse happening simultaneously. Asbedomonstrated in Section 1.5, the actual shear strength can varyconsiderably above a value ofNo clear conclusion canbe drawn as to whether punch through or collapse occurs first. Basedon the above discussion, the failure of the enclosure building willinvolve both extensive shear and flexure damage and it will deformuntil it comes into contact with the containment.1-13 FSAR1.5 Shear Capability of the Containment The enclosure building will deform until it comes into contactthe containment dome.The dome will then resist the impact forceand experience transverse shear stress in the vicinity of the impactarea. The maximum average shear stress is determined by defining ashear perimeter and thickness over which the impact force is acting.Figure 24 describes the procedure by which the shear perimeter forthe maximum average shear stress acting on the containment dome isdetermined.The shear perimeter for the containment is at adistance(effective depth of enclosure) + ( effective depth of containment 2away from theof the impact area.The values of the shear perimeter for various cross sections of theaircraft are given in Table l-4.Also shown are the shear area,impact force and average shear stress for the containment building.The values of average shear stress as a function of the cross sectioncrushed is shown in Figure 25. The shear stress is given interms of psi andThe maximum value of the average shear stressoccurs when the aircraft is crushing at a distance of 35 feet fromthe nose. The value of this maximum average shear stress is 229 psiorVarious shear strengths have been proposed.A tabulation of theseshear strengths, for parameters similar to the aircraft and structureunder discussion is shown in Table l-5.It is seen that the maximumnominal shear stress ofis less than all the otherproposed values except the conservative value ofas proposed by the1-14 G1.01-15B2.570.454dmxeVWKFSARXI-Committee 326.Hence, it is concluded the the containmentwill not fail by punch through.1.6 Requirements to Prevent Perforation The velocity of the engines as they impact on the enclosure buildingand containment is 250 fps.The FB-111 has two Pratt Whitney(Military designationjet turbo fan engines with an outside diameter of 50.22inches.Each engine has a dry weight of 4,121 pounds (Ref. 1).The thickness of the dome required for no performation was determinedusing procedures reported in Reference 7.The pertinent nomenclature is :penetration thickness for infinitely thick slab (inches)perforation thickness for reinforced concrete (inches)diameter of missile (inches)velocity of impact (feet per second)weight of missile180ultimate compression strength of concrete (psi)
FSARSince a jet engine is not completely solid (thin shells for torquetransmission, blades for fan, compressor and turbine, burner cans forcombustion) the engine was assumed to behave similarly to a hollowpipe missile.For a fan-jet, the outside diameter is slightly larger than the gasgenerator.Two values of dm (the diameter of the gas generator)were used, SO.23 inches and 40 inches. The results are:dm (inches)21.822.8These values can be compared with the dome thickness of 42 inches.From these calculations,can be concluded that there will be noperforation.1.7 ConclusionsFrom the above results of the analysis of theStationContainment,the following conclusions can be made:1.The enclosure building will fail and will come into contact withthe containment building.The mode of failure will not be byshear or flexure alone, but will involve both types ofdamage.2.The containment building will not fail.Thestrength willprevent collapse.The shear strength will prevent.punchThere will be permanent damage to the structure, but the extentof this damage will not be sufficient to cause loss of theintegrity of the building.l-16 FSAR3.The linerinelastic, will be sufficiently smallso that tearing of the liner will not occur.4.The engines will not perforate the containment.These conclusions can be made even though the above analysis wasperformed with considerableThe conservative aspectsof the analysis are:1.The reaction-time relationship was determined for impact on a rigidtarget. A realistic, flexible target would reduce the peak valueof the reaction.2.Normal impact was assumed.Any impact angle other thanreducesthe impact forceand increase the area over which the impactforce acts.3. The arcing effect of the doubly-curved dome was ignored. Archingincreases the collapse and punching load capacities.4.The shear stresses can be computed more accurately using theeffective forceduring the time necessary for thestructure to respond rather than the peak instantaneous force.The peak instantaneous force will give larger shear stresses thanthe effective force.5.The actual concrete compression strength will be larger than thespecified strength of 3,000 psi.This would result in a largervalue for the shear strength.6. A conservative estimate of the shear periphery used to calculateshear areas and shear strengths wasThe1-17 FSARfailure cone was assumed to be through the containment only andnot through the combined thicknesses of the containment andenclosure building,The latter would be more accurate.The integrity of the containment buildingnot be impaired in theoccurrence of the postulated aircraft impact.
1.8 REFERENCES
FOR SECTION 1.01."FB-111 Unit Inertia Data, "General Dynamics, Fort Worth Division,Report FZS-12-6010, Revision "A", January, 1968.2.Riera, J.O., "On the Stress Analysis of Structures Subjected to AircraftImpact Forces" Nuclear Engineering and Design, North Holland PublishingCompany, Amsterdam, Holland, 8p. 415-426.3.Ghosh, S., and Wilson, E., "Dynamic Stress Analysis of AxisymmetricStructures Under Arbitrary Loading", University of California,Berkeley, CA., Revised Sept., 1975.4.Biggs, J. M., Introduction to Structural Dynamics, McGraw-Hill, Inc.,1964, pps. 69-84.5. Meiorovitch, Analytical Methods in Vibrations, The Macmillan Company,1967, p. 183.6.Save and Massonnet, Plastic Analysis and Design of Plates, Shells and Disks, North Holland, 1972, p. 245.7.Kennedy, Effects of an Aircraft Crash Into a Concrete Reactor ContainmentBuilding.HolmesNarver, Inc., July, 1966.1-18
-478-478FSARTABLE l-lMAXIMUM RESPONSEANALYSIS(IMPACT AT DOME)MeridionalCircumferential Element 36 is elementabove springline.FSARTABLE 1-2RESPONSEASYMMETRIC ANALYSIS(IMPACT AT SPRINGLINE)Meridional-1139Ft-K/FtCircumferential-1309Meridional383Circumferential442Meridional-1148.Ft-K/FtCircumferential1350Meridional*378Circumferential431Element 37 is element immediately below springline.
SectionTABLE l-3ALLOWABLEFORCE, MAXIM?? RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATING TARGET MATERIAL RADII31.121.2331.151.1231.201.3331.251.47Participating Radius; since this is notdefined, a range of values isincluded.** By observation, Pigure 2.26,"Introduction to StructuralRiggs-3( 1.00 x 10-29.03 x1.61 x 104.92 x 10-2T4.01 x 10-33.61 x 10-26.42 x 10-24a12162024322.51 xCracked Section41.24x137.1a4.92x10-334.2121.12x10-215.2161.99x10-2a.53-210203.11x105.43-210244.48x3.8310286.09x2.83-210327.96x102.131011.101.201.101.301.171.361.231.471.251.70170.042.418.810.6 1-4AVERAGE SHEAR STRESSLocationShear Perimeterft.ft.Shear AreaReactionpoundsAverage ShearStresspsi*If the wings were assumed to have sheared-off at the time that the aircraft were crushing at this locationthe shear perimeter and reaction would-be reduced to 64.6 ft. andrespectively. The average shearstress then becomes 198 psi.the horizontal and vertical stabilizers were assumed to have sheared-off at the time that the aircraftwere crushing at this location the shear perimeter and reaction would be reduced to 42.1 ft. andrespectively. The average shear stress then becomes 209 psi.average shear stress for the case were the crushing strength is reduced by 5 is 245 psi.32.614,47437.016,42841.818,55950.222,28899.844,31145.520,20249.221,84449.221,84415193541505889229178686,00032 Ultimate Shear StrengthpsiUltimate Shear Strength71765560752752552344539138336335129221913.111.911.089.629.589.557.146.996.626.415.334.00SBFSARTABLE l-5COMPARISON OF ULTIMATE SHEAR STRENGTH CAPACITY*equation 5-2,equation 5-1,=equation S-10,=equation 5-5,=equation 5-2,= 1equation 5-3,=equation 5-1,= 1equation S-10,= 1equation 5-5,1equationequationequation 5-6equation 5-9,326shear stress at distanced/2 from periphery = 1*"The Shear Strength of Reinforced Concrete Member-Slabs",JointTask Committee426, Journal of the Structural Division, ASCE, Aug., 1974.c = 93"= 3,000 psip = 0.0099d37"Y60,000 psi**Adjusted for circular region,evaluated at d/2 away from periphery.
10 FT 3 INI.133FT., II IN.STA270.50STATICGROUND LINESTA562.97 704020Figure 2B E I G H TSB 1 2FSAR73.5---FigureI I I60040 8622FSAR TIMESECONDSFIGURE 3REACTION-TIME RELATIONSHIP 5PFSARP denotes the scale crushing load used in the calculation.and5 denotes that one-fifth and five time the crushing loadused,'respectively.1086T I M ESECONDSFIGURE 4Reaction-Time Relationship for FB-111 with impact velocities of 200 mph.
SB 1 & 2FSARFIGURE 5FINITE ELDIENT MODEL FSARNO.3S T A T I O NFIGURE.6FOURIER SERIES REPRESENTATION OF SPRINGLINE LOADING 00.050.100 . 1 50.200.250.30FIGURE 7 ACTUAL AND IDEAL REACTION TIME RELATIONSHIP MATERIAL,FSARFIGURE 8ALLOWABLE MAXIMUM FORCE, MAXIMUM RESISTANCE RATIO FOR VARIOUSDUCTILITY RATIOS AND PARTICIPATION TARGET MATERIAL RADII SBFIGUREBEHAVIOR ANDLINE CONFIGURATION FSARFIGURE 10.LOAD-DISPLACEMENT CURVE FOR REINFORCED CONCRETE SB 1FSAR
- 15.2 ft.30.2 ft.Shear PerimeterSBFSARFigure 13, Impact Area and Shear Perimeter at 8.5 Feet From Nose SBShear PerimeterEnclosure17.8 ft.Containment31.8 ft.Figure 14, Impact Area and Shear Perimeter at 9.9 feet From Nose SBShear Perimeter- -ft.Containment 32.6 ft.FigureImpact Area and Shear Perimeter at 15 Feet From Nose FSAR\\IShear PerimeterContainment37.0 ft.Figure 16, Impact Area and Shear Perimeter at 19.0 Feet From Nose Shear PerimeterContainment37 ft.FSARFigure 17, Impact Area and Shear Perimeter at 27 Feet From Nose FigureImpact Area and Shear Perimeter at 35 Feet from NoseShear Perimeter'Containment 50.2 Ft.SBFSAR
...Containment - 99 8 ftShear Perimeterm.MIN********.*1.Figure 19, Impact Area and Shear Perimeter at 41.0 Feet From Nose Shear PerimeterContainmentII43.2 ft.SB2FSARFigure 20, Impact Area and Shear Perimeter at 50.0 Feet From Nose Shear PerimeterContainment 49.2 ft.Figure 21Impact Area and Shear Perimeter at 58.0 Feet From NoseFSAR IDISTANCEFEET1010304050602FIGURE 22, REACTION-CRUSHING LOCATION RELATIONSHIP JPSI6.005.0025010012345671750DISTANCE CRUSHED-FT.Figure 23 Average Shear Stress-Distance Crushed and Reaction Distance CrushedRelationship for the Enclosure Building.
2Effective Shear Area24 SCHEMATIC FORSHEAR 25STRESS-DISTANCE CRUSHED RELATIONSHIP FOR CONTAINMENTDISTANCE CRUSHED229 PSI FSAR2.0FIRE HAZARD ANALYSIS OFSTATION CONTAINMENTFOR AIRCRAFT IMPACTA highly unlikely chain of adverse events is postulated in thefollowing manner:An FB-111 with a weight of 81,800 lbs and initial speed of 200mph impacts on one of the two double containment complexes of thebrook plant.The enclosure building deforms locally under the initialimpact,and the local deformation continues with little to no perforationuntil the enclosure building comes into contact with the containmentbuilding.This fact, plus the fact that if any penetration should occurit would be only the nose of the aircraft, will preclude the spillingof significant amounts of fuel into thespace. Thespacecontains no equipment,and all penetrations both mechanical and electricalare isolated from missiles and fuel by reinforced concrete slabs,Theenclosure building acts as a barrier and directs the spilled fuel to theexterior area near the enclosure building.The following effects werethen studied:Possible production of combustible vapor, its promptignition and the ensuing pressure pulse, and thepossibility that the combustible vapor may be suckedinto the plant areas and be cause for delayed ignitionor toxic atmosphere in habitability systems.The fuel spilled and its transport to various areas ofthe plant. An ignition is then postulated, and theeffect of the ensuing fire studied in order to evaluate2-l FSARthe safe shutdown capability of the plant.The effect of smoke and/or toxic gases as may be generatedby the fire, with particular reference to control roomhabitability.The effects as detailed in (1) and (3) for all smaller air-craft.2.1COMBUSTIBLE VAPOR PRODUCTION The FB-111 carries approximately 32,000 lbs of type JP-4 fuel. Asindicated in Reference 1, the process of combustible vapor production isas follows:the crashing aircraft drags along the ground in a relativelyslow deceleration (0.4 g) which lasts for a 'long' time (20and thefuel issuing from the wing after some postulated leakage mechanism isatomized to mist by the air as a result of its velocity relative to air.For the direct impact considered here,the decelerations are very high(peak value of 29 g) and of very 'short' duration (0.3 sec.).The atom-izing process under these conditions is not significant.It is, there-fore, concluded that the combustible vapor production and the associatedhazards can be considered to be mitigated.2.2FIRE ANALYSISVarious spill mechanisms are postulated either on the roofs or onthe ground adjacent to the containment structure:The various roof areas adjacent to the containment enclosurewith their elevation approximate areas, etc., are detailedin Table 2-1.As stated in PSAR Section 2.4, most of theseroofs have parapets, and the roof drainage systems aredesigned to drain at least 3 inches per hour rain. It is2-2 FSARnoted further that 1 inch of fuel takes 10 minutes toUsing the minimum area in Table 2-1, and acatastrophic instantaneous mode of fuel release, themaximum expected duration of the fire is 17.9 minutes.For ground areas adjacent to the containment, there isapproximately 1.5 acres of land, the total drainage ofwhich is approximately 6 cfs.The spreading of the fuelover this area and the adequate drainage would result ina film fire with width comparable to the roughness of thepavement, e.g.,inch.The resulting fire would lastonly for 1 minute at the most.The mechanism of fire propagation was examined. No flamm-able material is normally expected to be present next tothe containment which can serve as the propagator of thefire. The range of the fire has very conservativelyestimated to be 200 ft. from its point of origin.Smoke is postulated to be traveling from this centre firelocation carried by the wind.Its effect on the habitabilitysystems was then studied.The possible hazard of fuel getting into the PAB Buildingthrough the vent stack is considered remote due to the follow-ing reasons:The mechanism is improbable.The entering fuel will be drained off at the base ofthe vertical stack, just as rainwater would be.The possible hazard of fuel getting into the main steam linetunnels through the side vent openingsconsidered notprobable since the vent openings are above grade.2-3 FSAR2.3 EVALUATION OF VARIOUS SAFETY RELATED AREASThe various intake points to the safety related areas and theirdescription8 are detailed in Table 2-2,including the missile shieldswhen applicable, under the accident conditions detailed in Subsection2.3. All buildings other than the control room and the PAB residualheat removal area are either not needed for safe shutdown or are redun-dant.However, the conservative analysis below includes the reactionof these areas to the postulated fire.(a) Control Room There is no mechanism for the fire to endanger the habitabilityof the control room, since the split intake vents are at adistance of at least 300 ft. from the containment; therefore,it is beyond the reach of the direct fire. However, in theremote event that the fire finds its way into the intakestructure, the temperature and smoke sensors will sense itthe intake opening will be closed. Under theseconditions, the other intake will be used for ventilating thecontrol rooms.Primary Auxiliary Building (PAB) The air intake is located on the east wall of the primaryauxiliary building at an elevation ofThe area infront of the intake has the containment enclosure roofelevation ofand the east wall of the PAB faces thecontainment and the fuel storage building.There may be afire lasting 12.5 minutes at most on the roof of thecontainment enclosure area, a part of which may be injectedinto theair intake, as its height is 3 ft. above the2-4 FSARroof of containment enclosure area.The inside of thePAB has roll-type filters after the intake and heatingcoil panels after the filter.Therefore,the flame andthe hot gases would have to penetrate the filter and thecoils before reaching the fans.As indicated in Subsection 2.2, the roof surface of thecontainment enclosure area will be finished smooth andwith proper drainage to drain off the spilled fuel quickly.Smoke and heat sensors will be located at the air inlet sothat on a signal from them the operator can stop the fans.Diesel Generator BuildingThe diesel generator building intakes are on opposite sidesof the building and are located at least 180 ft. from thecontainment structures.It is considered improbable thatthe spilled fuel will find its way underneath one of theseintakes.Furthermore,the intakes are 28.5' above gradelevel, and it is unlikely that the fire will rise to thatheight.In addition, one of the intakes is shielded bythe diesel generator building and it is thus not consideredcredible that the fire could reach that intake.Althoughit may be postulated that the hot gas from thepoint may cause momentary oxygen starvation ofgenerator, the shielded intake will ensure theother diesel generator and of one train.Service Water Building direct intakeone dieselintegrity ofThe intake for the service water building is approximately280 ft. from the containment'and should be out of reach ofthe postulated fire.Furthermore,the air intake is located2-5 FSARin the east wall of the building.Consequently, thebuilding serves as a shield for the spilled fuel flow.Additionally, there is a missile shield in front of thestructure, which should inhibit any possible fuel flowand subsequent fire.The fire effects are, therefore,considered minimal. However, a minute amount of hot gasmay enter the facility, but since the pumps are locatedat the west end of the building, it will not criticallythreaten their operation due to rise of temperature.Vent StackThe vent stack is not a safety related item and, as in-dicated in Subsection 2.2, it does not furnish a significantpathway for the fuel to get into the primary auxiliary build-ing. This mechanism of fire propagation is, therefore, con-sidered incredible.Cable Spreading, Battery Room, Switch Gear Room and Cable Tunnel The air intake for cable spreading, battery room, switch gearroom and cable tunnel areas is through the mechanical equip-ment room of the diesel generator building, and the varioussafety aspects discussed for the diesel generator room holdfor this case.2.4HAZARDS FROM SMALLER AIRCRAFTThe smaller plane crashes were examined for the various areas, asdetailed in Subsections 2.2 and 2.3. The fuel in general may be JP-1,kerosene and JP-4.Since the fuel carrying capacity for all these planesis smaller than that of FB-111, and their burning temperatures are of thesame order of magnitude, it was concluded that the effect would be envelopedby those in the case of FB-111.2-6 FSARCONCLUSIONS In view of the results in Subsectionsandit was con-cluded that the hazard toStation from direct fire after thepostulated crash of an FB-111 or smaller aircrafts on the containmentrepresents only very minimal potential hazard to the plant.The presentdesign of the plant has inherent safety features so that the consequenceof this minimal hazard is mitigated.REFERENCES FOR SECTION 21.Appraisal of Fire Effects From Aircraft Crash at Zion PowerReactor Facility, I. Irving Pinkel,Consultant, Atomic EnergyCommission, July 17, 1972.Flammability Characteristics of Combustible Gases and Vapors,Bulletin 627, U. S. Bureau of Mines, 1965, Michael Zabetakis.
BUILDINGSROOFAREA(SQ.FT.)ELEVATIONREMARKSCONTAINMENT ENCLOSURE4,10053'WITH PARAPETEMERGENCYFEEDWATERPUMPBLDG.3,00047'WITH PARAPETFUEL STORAGE BUILDING9,20084'WITH PARAPETPRIMARYAUXILIARYBUILDING8,14481'WITH PARAPETPAB Filter Room2,856108'WITH PARAPETTABLE 2-lROOF DESCRIPTIONSNOTE:GRADE ELEVATION 20' TABLEVENTILATION SYSTEM DESCRIPTIONS OF THE BUILDING SURROUNDING THE CONTAINMENT .,SHEET 1 OFBUILDINGBUILDINGSURFACEFACING THE CONT.LOCATIONS OF THEINTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMCONT.WALLELEVATIONDieselGen.South wallSouthWall200 ft.28.5ft.above gr.Other Bldg.at 40'dist..Ventilationair;notnecessaryforsafeshutdown.NorthWall240 ft.(thruroof)28.5 ft.aboveOther Bldg.at40PABEast wallEastWall20 ft.3aboveadjacentroof.Shielded bythe Cont.F.Stg.Bldg.Normalventilationair;only RHRpump area safeshutdownrelated.NorthWall95ft.(thruroof)29ft.above gr.thickshield.Ventilationairtosafety relatedmary component cool,ing water pump areaand Boron injectionpump area.EmergencyFeedwaterPump Bldg.South WallNorthWall30 ft.(thruroof)18ft.above gr.2'thickconcretemissileshieldVentilationairtothe emergencywater pump area.
TABLE 2-2 (CONT.)SHEET 1 OF 2BUILDINGBUILDINGSURFACEFACING THE CONT.LOCATION OFTHE INTAKESTYPE OFSHIELDINGREMARKSSURFACEPATHWAYFROMELEVATIONCONT.WALLServiceWaterPumpHouseWest WallEastWall290ft.(throof)ru45 ft.above2'thickmissileshield.Ventilationairtotheservice waterpump house.WestWall180ft.13.5above2'thickmissileshield.Air intake to theelectricalareas.ControlRoomComputerRoomSouth 6EastWallsRemoteIntakePorts300ft.least)At gr.levelCoveredwithgrating.Ventilationairtothe habitable areasof the control andcomputer room.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-1 APPENDIX 2Q EAB AND LPZ SHORT TERM ACCIDENT DIFFUSION ESTIMATES FOR AST 2Q.1 OBJECTIVE Conservative values of atmospheric diffusion at the site boundary (EAB) and the low population zone (LPZ) were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2Q.2 METHODOLOGY The methodology used for this calculation is consistent with Regulatory Guide 1.145 as implemented by the PAVAN computer code (Reference 2). Using joint frequency distributions of wind direction and wind speed by atmospheric stability, the PAVAN computer code provides relative air concentration (CHI/Q) values as functions of direction for various time periods at the site boundary and LPZ. Three procedures for calculation of CHI/Qs are utilized for the site boundary and LPZ; a direction-dependent approach, a direction-independent approach, and an overall site CHI/Q approach. The CHI/Q calculations are based on the theory that material released to the atmosphere will be normally distributed (Gaussian) about the plume centerline. A straight-line trajectory is assumed between the point of release and all distances for which CHI/Q values are calculated. The theory and implementing equations employed by the PAVAN computer code are documented in Reference 2. 2Q.3 CALCULATIONS/PAVAN COMPUTER CODE INPUT DATA The boundary distance used in each of the 16 downwind directions from the site was set to 914 m. The LPZ boundary distance was set to 2,011 m. All of the releases were considered ground level releases because the highest possible release elevation is from the plant stack at 185 ft above plant grade. From Section 1.3.2 to Reference 1, a release is only considered a stack release if the release point is at a level higher than two and one-half times the height of adjacent solid structures. For the Seabrook plant, the elevation of the top of the containment is 199.25 ft. Therefore, the highest possible release point is not 2.5 times higher than the adjacent containment buildings, and thus all releases were considered ground level releases. As such, the release height was set equal to 10.0 meters as required by Table 3.1 of Reference 2. The building area used for the building wake term was 2,416 m2.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS EAB and LPZ Short Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2Q Page 2Q-2 The tower height at which the wind speeds were measured is 10.05 m above plant grade. The windspeed units are given in miles per hour, therefore the PAVAN variable UCOR was set equal to 101 to convert the windspeeds to meters per second as described in Table 3.1 of Reference 2. The maximum windspeed in each windspeed category was chosen to match the raw joint frequency distribution data, which conforms to the windspeed bins in Table 1 of Reference 3. 2Q.4 RESULTS PAVAN computer runs for the EAB and LPZ boundary distances were performed using the data discussed previously. Per Section 4 of Reference 1, the maximum CHI/Q for each distance was determined and compared to the 5% overall site value for the boundary under consideration. For dose calculations, the most limiting 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> CHI/Qs were combined with the worst 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> EAB doses to maximize calculated EAB doses (conservative approach). The maximum EAB and LPZ CHI/Qs that resulted from this comparison are provided in the table below: Offsite Boundary /Q Factors for Analysis EventsTime Period EAB /Q (sec/m3)LPZ /Q (sec/m3) 0-2 hours 3.17E-041.54E-04 0-8 hours 2.08E-048.63E-05 8-24 hours 1.68E-046.46E-05 1-4 days 1.06E-043.45E-05 4-30 days 5.51E-051.40E-05 2Q.5 REFERENCES 1. USNRC Regulatory Guide 1.145, "Atmospheric Dispersion Models for Potential Accident Consequence Assessments at Nuclear Power Plants," Revision 1, November 1982, (Reissued February 1983 to correct page 1.145-7). 2. NUREG/CR-2858, "PAVAN: An Atmospheric Dispersion Program for Evaluating Design Basis Accidental Releases of Radioactive Materials from Nuclear Power Stations," November 1982. 3. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-1 APPENDIX 2R SHORT-TERM (ACCIDENT) DIFFUSION FOR THE CONTROL ROOM 2R.1 OBJECTIVE Conservative values of atmospheric diffusion to the Control Room were calculated for appropriate time periods using meteorological data collected onsite during the time period 1998 through 2002. 2R.2 METHODOLOGY The ARCON96 computer code is used by the USNRC staff to review licensee submittals relating to control room habitability (Reference 1). Therefore, the ARCON96 computer code was used to determine the relative concentrations (CHI/Qs) for the control room air intakes and inleakage locations. The ARCON96 computer code uses hourly meteorological data for estimating dispersion in the vicinity of buildings to calculate relative concentrations at control room air intakes that would be exceeded no more than five percent of the time. These concentrations are calculated for averaging periods ranging from one hour to 30 days in duration. The theory and implementing equations employed by the ARCON96 computer code are documented in Reference 1. 2R.3 CALCULATIONS/ARCON COMPUTER CODE INPUT DATA Five years of meteorological data (1998-2002) were used for the ARCON96 computer code runs. The percentage of valid data over this time period was 98.8% which exceeds the minimum value of 90% data recovery specified in Reference 2. A number of various release-receptor combinations were considered for the control room CHI/Qs. These different cases were considered to determine the limiting release-receptor combinations for the various events. The case matrix for these combinations is provided in Table 2R-2. The distance and direction inputs for the ARCON96 runs may be found in Table 2R-1. The distances were converted from feet to meters with a factor of 0.3048 m/ft. The distances in meters were then rounded down to the nearest tenth for conservatism. The elevation difference term was set equal to zero for each case since all elevation points are taken with respect to the same datum.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-2 The lower and upper measurement heights for the meteorological data were entered as 10.05 m and 60.66 m, respectively, for each case. The mph option was selected for the windspeed units. A ground level release was chosen for each scenario since none of the release points are 2.5 times taller than the closest solid structure as called out in Section 3.2.2 of Reference 3 for stack releases. The top of the containment structure is at an elevation of 199.25 ft. The highest release point is from the top of the plant stack at an elevation of 185 ft., which is not 2.5 times higher than the nearby containment structure. The vertical velocity, stack flow, and stack radius terms were all set equal to zero since each case is a ground level release. The vent release option was not selected for any of the scenarios. The actual release height was used in the cases. No credit was taken for effective release height due to plume rise; therefore, for the releases from the stacks, the release elevations were set equal to the stack top elevation. The release heights were taken as the release elevations less the plant grade elevation of 19 ft. The only cases in this analysis that take credit for the building wake effect are the scenarios where the release is from the containment building, the tank farm, or the waste processing building. Some of the other scenarios have buildings between the release and receptor points, but for these cases the building wake was not credited for the sake of conservatism. Not crediting wakes was accomplished by setting the building area term equal to 0.01 m2 as stated in Table A-2 of Reference 3. The first building area used is a conservatively determined containment cross sectional area. The area is calculated as the sum of the cross sectional areas created by the cylindrical portion of the containment structure above the highest nearby roof and the hemispherical area of the dome. The width used is equal to the diameter of the containment structure. The height of the cylindrical portion is taken as the distance between the top of the cylinder portion of the containment structure (represented by the spring line elevation) and the primary auxiliary building roof elevation. The radius of the hemispherical dome is taken as one half of the calculated diameter. The containment area was determined to be 1,506 m2. The second building area is calculated as the product of the minimum roof height of the waste processing building and tank farm and one half the width of the waste processing building and tank farm. The minimum roof height and one half of the width are used for conservatism. This building area was determined to be 337 m2. All of the default values in the ARCON96 code were unchanged from the code default values with the following exceptions. Table A-2 of Reference 3 suggests use of a value of 0.2 for the Surface Roughness Length, and use of a value of 4.3 for the Averaging Sector Width Constant. These two changes were made for each case. The minimum wind speed was left at 0.5 m/s per the guidance instruction in Table A-2 of Reference 3.
SEABROOK STATION UFSAR ACCIDENT ANALYSIS Control Room Short-Term (Accident) Diffusion Estimates for AST Revision 10 Appendix 2R Page 2R-3 2R.4 RESULTS ARCON96 computer runs for the various release points and control room intake locations were performed using the data discussed previously. Per Reference 3, the 95th percentile CHI/Q values were determined. The resulting CHI/Qs are listed in Table 2R-2. 2R.5 REFERENCES 1. NUREG/CR-6331 PNL-10521, "Atmospheric Relative Concentrations in Building Wakes," May 1995, with Errata dated July 1997. 2. Safety Guide 23, "Onside Meteorological Programs," February 17, 1972. 3. USNRC Regulatory Guide 1.194, "Atmospheric Relative Concentrations for Control Room Radiological Habitability Assessments at Nuclear Power Plants," June 2003.