ML19221A908

Reg Guide 1.90,Revision 1, Inservice Insp of Prestressed Concrete Containment Structures W/Grouted Tendons

ML19221A908
Person / Time
Issue date:	08/31/1977
From:	NRC OFFICE OF STANDARDS DEVELOPMENT
To:
References
REGGD-01.090, REGGD-1.090, NUDOCS 7907100329
Download: ML19221A908 (12)

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OFFICE OF STANDARDS DEVELOPMEWT REGULATORY GUIDE 1.90 INSERVICE INSPECTION ve' PRESTRESSED CONCRETE CONTAINMENT STRUCTURES WITH GROUTED TENDONSt A. INTRODUCTION deleterious environment, (3) the extent of temperature sariations, and (4) the quality of the General Design Criterion 53, " Provisions for Con-grout and its installation. Following the recommerr tainment Testing and Inspection," of Appendix A, dations of Regulatory Guide 1.107, " Qualifications

" General Desien Criteria for Nuclear Power Plants,'

for Jement Grouting for Prestressing Tendons in to 10 CFR Part 50. " Licensing of Production and Containment Structures," could significantly reduce Utilization Facilities," requires, in part, that the con-the danger of widespread corrosion. Floweser, the tainment be designed to permit (1) appropriate mechanism of corrosion in all conditions and situa.

periodic inspection of all important areas and (2) an tions is not fully understood. Because many appropriate surveillance program. This guide parameters can influence the deselopment of corro-describes bases acceptable to the NRC staff for sion or stress corrosion, there is always an area of un-developing an appropriate surseillance program for certainty with regard to the corrosion of tendon steel, prestressed concrete containment structures with and it is necessary to monitor the structure in a man-grouted tendons. The Adsisory Committee on Reac-ner that w ould reveal the existence of widespread cor-tor Safeguards has been consulted concerning this rohon.

guide and has concurred m the regulatory position.

f his guide outlines the recommendations for inser-4 B. DISCUSSION sice inspection of containments having grouted Insersice inspection of prestressed concrete con.

tendons of sizes up to an ultimate strength of approx-tainment structures with grouted tendons is needed to imately 1300 tons (lI.000 kN) and consisting either serifv at specific intervals that the safety margins of parallel wires or of one or several strands. The pt ov'ided in the design of containmcni structures bas e detailed recommendations of the guide are not direct-not been reduced as a result of operating and en-ly applicable to grouted tendon containments having bar tendon s.

flow ever, the inservice inspection sironmental conditions. Grouting of tendons to program for grouted 'endon conta;nments with bar protect them against corrosion is a proven technology in other types of structures. liowever, tendons may be devch. cd u,ing the principles in this there is as set no real experience to adequately define guide and will be reviewed by the NRC staff on a the lone-term characteristics of containment strue, case-by-case basis. This guide does not address the in-tures with grouted tendons. The major concern in service inspection of prestressing foundation anchors.

containment structures with grouted tendons is the if they are used, the inservice inspection program will possibility that v.idespread corrosion of the tendon be resiewed by the NRC staff on a case-by-case basis.

steel may occur and remain undetected. The major Inservice inspection of the containment liner and factors influencing the occurrence of corrosion are (l) penetrations is also not addressed in this guide.

the susceptibility of the tendon steel to corrosion,(2)

The simplest means of monitoring these prestres-the degree of ' exposure of t e tendon steel to a h

sed concrete structures would be to ascertain the E

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+ 1 or the rurpose of this guide, a tendon is deGned as a tensioned strain gages, stress meters, and strain meters,'is not ueel eiemeri msisune of w:res. ur.mds. er hars anshored at cash end to an enJ anchorage assemby reliable enough to provide such information. When USNRC RF.GULATGRY GUIDES 0 -~ n "o e e ' o - * %ae u

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mstruroentation that either can be recahbrated or concrete creep arm shrinkage and relaxation of the replaced m case of a malfunction or is prosen to be tendon steel.

deseloped, monitoring the suf ficiently reliable is The measurement of forces in ungrouted test prestress lesel uould be a desirable means of assess.

tendons would proside a quantitative means of mg the continuing integrits of prestressed concrete structures with grouted tendons _

s erifying the design assumptions regarding the

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solumetric changes in concrete and the relaxation of Another means of monitoring the functionality of prestressing steel. If some 14t-off readings (or load the containment structure would be to subject it to a cell readings) ir.dicate valura lower than the expected low values, checks shodd be made to determine if pressuie test and measure its behavior under pres-such values are due to corrosion of wires of un-sure. lndustry comments indicate that an insersice in.

spection program based on the test of oserall func.

grouted tenaons or to underestimation of prestress-tionahty is preferable.

ing losses. The plant need not be shut down or main.

tained in a shutdown condition during such an This regulatory guide prosides two acceptable evaluation period. These tendons may also serve as altern stise methods ofinspecting containment struc-an investigative tool for assessing the structural con-tures with grouted tendons: (1) an insersice inspec-dition after certain incidents that could affect the tion program based on monitoring the prestress lesel containment.

by means of instrumentation, and (2) an inservice in-L N10NITORING AI. TERN ATIV ES FOR spection program based on pressure-testing the con-GROUTED TENDONS tamment structure.

a. N1onitoring of Prestress Icel ( Alternative A)

The detailed inspection program outlined in this guide is applicable to a sphere-torus dome contain.

After the application of prestress, the prestressing force in a tendon decreases owing to the interaction ment hasing cylindrical walls about 130 feet (40 m)in f such factors as:

diameter and an overall height of about 200 feet (61 m) with three groups of tendons, i.e., hoop, sertical-(1) Stress relaxation of the prestressing steel; and dome. For the purpose of this guide, such a con-tainment is termed the " reference containment." The (2) Volumetric changes in concrete; recommendations in the guide may be used for similar containments with cyhndrical walls up to 140 (3) Differential thermal expansion or contraction feet (43 n.) in diameter and an oserall height up to between the tendon, grout, and concrete; and 210 feet (64 m).

(4) Possible reduction in cross section of the wires For containments that differ from the reference due to corrosion, including possible fracture of the containment or are under a controlled ensironment, wires.

the inseruce inspection program may be deseloped using the concepts esobed in this guide and the in this atternatise, the prestress level is manitored guidehnes in Appendix A.

at certain strategically located sections in the contain-ment. Thus it is a sampling procedure in which The inseruce inspection program recommended in degradation in the vicinity of the instrumented sec-this guide consists of.

tion will be detected by evaluation of the instrumen-tation readines. However, if corrosion occurs at loca-

1. Force monitoring of ungrouted test tendons; tions away from the instrumented sections, it would

2. N1onitoring performance of grouted tendons by hase to produce gross degradation before the in-

a. N1onitoring of prestress lesel, or

b. N1onitoring of deformation under pressure; The prestressing force imparted to the structure by and a grouted tendon system could be monitored by an

3. Visual examinat:on.

appropriate combination of the following methods:

1. FORCE N10NITORING OF UNGROUTED (1) N1onitoring the tensile strains in the wires of a TEST TENDONS tendon:

Some tendons (otherwise identical) are left un-(2) Evaluating the prestress level at a section in the grouted and are protected from corrosion with structure from readings of appropriately located grease. The changes obsers ed in these tendons are not strain gages or strain or stress meters at the section mtended to represent the changes due to ensironmen-(see Refs. I through 7).

tal or phssical effects (with respect to corrosion) in the grouted tendons. Instead, these test tendons will N1ethod (1) above is useful for direct monitoring of be used as reference tendons to esaluate the extent of prestressing force in a tendon. Howeser, the installa-126 051 i,02

tion of the instrumentation required for this method anchorage takeup, and friction. The 8; bandwidth needs careful attention during installation and would amount to between 407 and 707 of the tota, grouting of the tendons. Moreoser, strain gages in-time-dependent losses.

stalled on the prestressing wires of a tendon will not detect the loss of force due to relaxation of prestress-Alternatise A is based on the use of instrumenta-ing steel. Allowance for this can be based on relaxa-tion. Many of these instruments have to be built into tion data for the prestressing steel used.

the structure in such a manner that they can be neither replaced nor reeahbrated. It is quite likely Esaluation of strain gage and stress meter readings that such built-in instrumentation may not remain requires a full understanding of what makes up the reliably operable throughout the life of the structure.

readings, e g., clastic, creep, and thermal strain or Recognizing such a possibility, the guide prosides for stress components. Strain gage readings will consist an alternative of pressure testing (Alterr.atise B) of elastic strains corresponding to the prestressing w hen the data obtained from instrumentation stress in concrete and strains due to creep and readings are found to be questionable.

shrinkage of concrete. Strains from creep and

b. Monitoring of DeformsSon Under Pressure shrinkage of concrete can sary between 1.5 and 2.5

( Alternati,e B) times the elastic strains in concrete. liowever, there are methods that can be used to isolate these effects.

Testing the containment under pressure and Three such methods are:

evaluating its elastic response has been proposed as a means of assessing the integrity of the containment.

(I) Calculate aserage creep and shrinkage strains The clastic response under pressure testing is primari-from the time-dependent losses measured on the un-ly a function of the stiffness of the structure. Any grouted tendons significant decrease in the stiffness of the structure due to loss of prestress would be the result of crack-(2) Use stress meters at sections w here strain gages ing of the structure. Because of the insensitive and in-are used.

direct relationcip between the prestressing force and the elastic response of the structure, such a method (3) Use special strain meters that respond only to cannot be used to estabbsh the existing prestress lesel volumetric and temperature changes in concrete at various sections. Iloweser, comparison of the con-(Ref. 7).

dition and deformation of the structure during the ISI (Inservice inspection) pressure testing with those A sufficient number of temperature sensors instal-during the ISIT (Initial Structural Integrity Testing) led at the sections where instrumentation is located pressure testing could provide a basis for evaluating can be useful in isolating the thermal effects. It is the functionality of the structure. This method has recognized that the raw instrumentation readings can been accepted

• previously by the NRC staff on the be deceptise, and adjustments may be necessary to condition that the containment be designed conser-account for the calibration constants and vat;vels so tha' there will be no cracking (or only temperature effcets. The intcrprctation and esatua-s ight cracking at the discontinuities) under the peak tion of the results will be simplified if the instrumen-test pressure. Section 111, Division 2, of the ASME tation is prosided at sections away from structural Code (Ref. 8) allows a 33-l/37 increase in the al-discontinuities. The cppbcant should proside suf.

Iowable stress in tensile reinforcement urder a test ficient redundancy in the instrumentation to permit condition. The NRC staff has accepted this al-the esa:uation of anomalous readings and the isola-lowance on the assumption that it is only a one-time tion of a malfunctioning gage.One such combination loadine (i e., during the ISIT). Howeser, if such would be two strain gages and one stress meter at testing'is to be performed a number of times during each face of a section.

the i.h of the containment structure,it is pradent not to use this allowance in order to avoid or mimmize After appropriate use has been made of the gradual propagation of cracking during subsequent methods and instruments asailable, an average stress pressure tests.

and an aserage prestressing force at a section can be evaluated. Even though the predicted prestressing The locations for measuring the deformations un-force corresponding to a specific time may include der pressure should be based on the recommenda-adequate consideration for creep of concrete and tions of this guide. For a meaningful comparison of relaxation of prestressing steel, the chance that the the deformations, it is recommended that the loca-value based on measurements will tuitipate wcll with tions w here the deformations are to be recorded hase the predicted value is small. Hence it is recommended deformations larger than 0.06 inch (1.5mm) under the that an applicant establish a band of acceptable calculated peak containment internal pressare as-prestress lesel similar to that illustrated in Figure I. it sociated with th6 design basis accident and that these is also recommended that the bandwidth not exceed 87 of the imtial prestressing force at a section after

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i, - Initial prestressing force at a secti<>n considering the losses due to elastic shortening, anchorage taksup, and friction.

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3. The insersice inspect on program should consist i

locations be approximately the same during the ISIT Of:

and the subsequent Isis. This will require these loca-tions to be away from the areas of structural discon-tinuities. Thus the number of locations for measure-

a. Force monitoring of ungrouted test tendon.

ment of deformations in typical cylinder and dome

b. Periodie reading ofinstrumentation for deter-areas wili be in excess of those recommended in Regulatory Guide 1.18. "Stractural Acceptance Test mining prestress level (Alternatise A) or deforma-for Concr'ete Primars Reactor Containments; tions untfer pressure (Alternatise B) at preestabbshed sections; and if an analysis of the effects of such parameters as

c. \\,i ual examination.

s normal losses in prestressing force, increase in modulus of elasticity of concrete with age, and dif-ferences in temperatures during sarious pressure tests

4. The inservice inspection should be performed at indicates that they could affect the dcformations of approximately 1,3, and 5 sears after the initial struc-the selected points, these parameters should be car tural integrity test and 'eserv 5 scars thereafter.

sidered in comparing the deformations durir "

Floweser, w hen an applicant c$oosci pressure testing sarious pressure tests.

(A ternatise B) as a part of the mspection. the fre-quency 0f inspections should be as indicated in

3. VISUAL FX OllN ATION Figure.3 Visual examination of structurally critical areas consisting o.be areas of structural discontinuities

5. Alternatise B may be substituted for AlWnative and the areas of hem strus concentration i< recom-A by the applicant if, at some time during the ofe of mend:.d. Referente 9 provides excellent guidance for the ' structure, the inspection based on Alternatise A reporting the condition of concrete and should be does not provide satisfactory data. The details of usd wheneser appheable for reporting the condition such a substitution will be resiewed by the NRC staff of examined areas-on a case-by-case basis.

There are numerous uamples of the use of pulse selocity technique to obtain information concerning

6. If the containment base mat is prestressed, its the ge,eral quality tesel of concrete. Based on ex-proposed inspection program w JI be esaluated by the perience and experimental data (Refs. 10,11,12), a NRC staff on a case-by-case basis.

pulse selocity of 14.000 ft/sec (4300 m/sec) or higher indicates a good to excellent quality of concrete. For normal weight concrete, a pulse selocity of 11,000

2. UNGROUTED TEST TENDONS ft/see (3400 m/see) or lower indicates concrete of questionable quahty. Thus the technique can be used I. The following ungrouted test tendons should be part of the inspection of concrete containments installed in a representatne manner:

as when the sisua! examination reseah a Lich densits of

a. Three urtical tendons, wide ( > 0 01 in. or 0.25 mm) crack, or otherwise heau deeradation. The detailed procedure and limit a tio n's of the techniques are described in

b. Three hoop tendons, and Reference 13.

c. Three dome tendons for the design utilizing three 6F families of tendons.

C. REGULATORY POSITION

2. The ungrouted test tendons need not be in add:-

I EMNAL tion to the design requirements.

1. All prestressed concrete containment structures with grouted tendons should be subjected to an inser-

3. The ungrouted test tendons and their sice mspection (ISI) program. The specific guidelines anchorage hardw are should

. identical to the prosided herein are for the reference containment grouted tendans and their haraw are.

described in Section B.

4. The ungrouted test tendons should be subjected

2. For conta;nments that differ from the reference to force measurement by lift-off testing or load cell, containment, the pregram described here:n should to assess the effects of concrete shrinkage and creep sers e as the basis for cies elopmg a comparable inser-and relaxation of the tendon steel. These data should 9

vice inspection program. Guidelines for the deselop-be evaluated in conjunction with the oserall struc-ment of such a program are gnen in Appendix A to tural condition of the contamment esident from the this guide.

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GROl'TED TENDONS MPa) stress variation in compression.

2. The instruments should be protected against 3.1 Instrumentation for Monitoring the Prestress udserse ettects of the expected environment in which Leiel i Alternative A) t ney will be located, e g., e.ectrcly ut etack, including

'he effects of stray electri: currents of a magnitude 3.I.1 Installation

. hat may be eneocntered at the particular site and structure. They shoulc be protected against

1. The prest essed cylindricci wall and dome temperature extremes to which they may be exposed saould be instrumented. This instrumentatior may be while the containment is under construction.

e ther embedded in the concrete or inserted into the structure so that it can be maintained or replaced.

3. The sensitivity of strain gages snould be ir strument types, locations, and quar.tities s nould be specified; the drift or rtability under the conditions in s.lected to provide the best representation of I and 2 abose should be accounted for in the prestress lesel in the structure. A sufficient n amber of specified limits, or the gages should be subject to teinperature sensors should be installed o isolate and recalibration in service.

ewluate the effects of variatio6s in terr permture gradierts on the instrum,.nt readings and observa.

4. The stress meters should be able to measure tic.s. Redundancy of the embedded instrurrentation compressive stresses up to 2500 psi (17.2 MPa).

should be based on a consersatise estimate of the 3.1.3 Monitcring Instrumentation Operability probability of malfunction of the instrum:mation to be installed.

After the instaliation of the instrumentation, all e.nbedded strain gages and stress meters should be

2. The instrumentation in the concrete should be read every two months until the initial structural in-arranged and distributed in such a manner as to per.

tegrity test (ISIT) is performed. The response of the mit evaluation of the prestressing levels and should instrumentation during prestressing and pressure be located:

testing (ISIT) should be used to confirm their operability. fler the ISIT, the monitoring of the in-

a. At six horizontal planes so ineasure the hoop strumentation should be continued every two months prestresting lesels; to confirm operability of the instrumentation until the first inservice inspection. The monitoring fre-

b. Along three sertical tendons to measure ver-quency may be reduced to once every six months tical prestress lesels; thereafter unless local conditions or special circum-stances dictate no, frequent readouts. The

c. Along three dome tendons for the design us-operability of the insm smentation should also be ing thac families of 60 tendons.

confirmed during subsequent pr(ssure tests. If anoma' s rndings are obtained the reason for such

3. Sections through the structure shot.ld be read. cgs should be determined If it is determined selected at a minimum ei four locations in each that thev result from defective gages, the basis for horizental plane, three locations along each sertical such a determination should be justified.

tendon, and two locations along each dorre tendon (see Figure 3). At these sections, the prestress lesel 3.2 Monitoring Deformation Under Pressure i Alter-should be monitored by (a) a combina$n of stress nstine B) meters or strain pages in concrete or or; rebar at a minimum of two points through the section or (b)

When it is pinned to use this alternatise as a part strain pages directly on tendon wires with a minimum of the total inservice inspection program it is recom-of 3'i of the tendon wires instrumented.

mended that the design of the containment structure include the following considerations:

3.1.2 Characteristics

1. Membrane compression should be maintained

1. Instrumentation prosided for the determination under the peak pressure expected during the ISI tests.

of concrete pres'.ress level shouid be capable of effec-tise use oser the life span of the containment struc-

2. The maximum stress in the tensile reinforcing ture within specified operational hmits under the fol-under the peak pressure er xd during the ISI test lowing condit;ons, unless otherwise defined by the should not exceed one-half t... yield strength of the Jesigner and approved by the NRC staff:

reinforcing steel (0.5f ).

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a. Humidity: 07 to 1007; 3.2.1 Pressurization

b. Temperature: 0 F (-18 C) to 200 F (93 C);

1. During the first inspection, tne containment and' ltructure need not be pressurized.

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2. Durirg the second and third inspections, the

3. Local areas around penetrations that transfer containment structure should be subjected to a max high loads to the containment structure (e.g., around imum internal pressure of 1.15 times the containment high-energy fluid system lines).

design pressure.

4. Other areas where heavy loads cre transferred

3. During the fourth and subsequent inspections, to the containment structure (crane supports, etc.).

.he containment structure should be subjected to a maximum internal pressure equal to the calculated A visual examination of structurally critical areas peak internal pressure associated with the postulated should be scheduled during all pressure tests while desip basis accident.

the containment is at its maximum test pressure, es en if visual examinations of these areas have been con-ducted at other times.

3.2.2 Instrumentation and Deformations 4.2 Anchorage Assemblies

1. Instrumentation similar to that used during the ISIT should be installed prior to the pressure testing Exposed portions of the tendon anchorage as-for measurement of oserall deformations at the sembly hardware or the permanent protection selected points.

thereon (whether it be concrete, grout, or steel cap) snould be visually examined by sampling in the fol-

2. The limit of accuracy of readings of the instru-lowing manner:

ments to be used should be specified by means of an error band so that a meaningful comparison of defor-

1. A minimum of six dome tendons, two located in mations measured during the ISIT and ISI can be each 60 group (three families of tendons) and ran-made.

domly distributed to provide representative sampl-

ing,

3. The points to be instrumented for the measure-ment of radial displacements should be determined in

2. A minimum of fhe vertical tendons, randomly six horizontal planes in the cylindrical portion of the but representatively distributed, shell, with a minimum of four points in each plane (see Figure 3).

3. A minimum of ten hoop tendons, randomly but representatisely distributed.

4. The points to be.astrumented for the measure-ment of sertical (or radial) displacements should be For each succeeding examination, the tendon determined as follows:

anchorage areas to be examined should be selected on a random but representatise basis so that the sample

a. At the top of the cylinder relatise to the base, group will change each time.

at a minimum of four approximately equally spaced azimuths.

The inservice inspection program should define the defects the inspector should look for during visual ex-

b. At the apex of the dome and one intermediate amination of the exposed anchor hardware and pomt between the apex and the springline, on at least protection medium and should establish the cor-three equally spaced azimuths.

responding limits and tolerances. Special attention should be gisen to the concrete supporting the anchor

5. T he intermediate pressure levels at which the assemblies, and any crack patterns at these points deformations at the selected points are to be should be obsersed and analyzed.

measured should correspond to those for the ISIT.

5. REPORTAHl.E CONDITIONS 5.1 Inspection Using Alternati$e A 4, VISU Al. EX AMINATION If the aserage prestress force along any tendon falls 4.1 Structurally Critical Areas below the acceptable band (see Figure 1). the condi-tion should be considered as reportable.

A visual examination should be performed on the following exposed structurally critical areas:

If the prestress force determined at any section falls below the design prestress force, the condition should

1. Areas at structural discontinuities (e.g., junction be conside;ed as reportable.

of dome and cylindrical wall or wall and base mat).

5.2 Inspection Using Alternative 11

2. Areas around large penetrations (e.g., equip-ment hatch and air locks) or a cluster of small If the deformation measured under the maximum penetrations.

test pressure at any location is found to have in-126 058

=

crezsed by more than Soc of that measured during the

6. REPORTING TO Tile COMMISSION ISIT under the same pressure, the condition should be considered as reportable.

The reportable conditions of Regulatory Position C.5 could be indicative of a possible abnormal de-5.3 Reportable Conditions for Visual Examinations gradation of the containment structure (a boundary designed to contain radioactive materials). Any such if the crack patterns observed at the structurally condition should be reported to the Commission.*

critical areas indicate a significant decrease in the spacing or an increase in the widths of cracks com-D. IMPLEMENTATION pared to those observed during the ISIT at zero pres-sure after depressurization, the condition should be The purpose of this section is to provide informa-considered as reportable.

tion to applicants and licensees regarding the NRC staff's plans for using this regulatory guide.

If the visual examination of the anchor nardware indicates obvious mosements or degrada'. ion of the Except in those cases in which the applicant anchor hardware, the condition should be considered proposes an acceptable alternative method for com-as reportable.

plying with specified portions of the Commission's regulations, the method described herein will be used if the anchor hardware is coverec' by permanent in the evaluation of submittals in connection with protection and the visual examiration reveals a construction permit applications docketed after degradatien (e g., extensive cracks or corrosion October I,1977.

stains)-that could bring into question the integrity and effectiveness of the protecticn medium, the con-If an applicant wishes to use this regulatory guide dition should be considered as reportable.

in developing submittals for applications docketed on or before October I,1977, the pertinent portions of 5.4 Reportable Conditions for Ungrouted Test the application will be evaluated on the basis of this Tendons guide.

When the force monitor.ng (by liftoff or load ce'l)

• The report to the Commission should be made in accordar.cc of ungrouted test tendons indicates a prestress force w ith the recommended reporting program of Regulatory Guide below the acceptable ba id (see Figure 1), the condt-1.16.

"R eporting of Operating i n f or mation-A ppend n A tion should be conside ed as reportable.

Tethnical Specifications?

O m e 1.90-10

J.PPENDIX A GUIDELINES FOR DEVELOPING THE INSERVICE INSPECTION PROGRAM FOR CONTAINMENTS (OTHER THAN REFERENCE CONTAINMENT DISCUSSED IN THE GUIDE) WITH GROUTED TENDONS Ungrouted Tendons Monitoring Deformations Under Pressure ( Alternatise B)

Three ungrouted tendons should be provided in The r. umber of locations (N) to be selected for each group of tendons (e.g. vertical, hoop, dome, in-measuring the deformations under pressure should be verted Ut determined as follows:

lostrumentation ( Alternathe A)

For radial deformations of cylinder, The following criteria should be used to determine Surface Area of Cylinder in square feet the number of sections (N) to be monitored for each (square meters) group of tendons:

N'

=

2700 (250)

N = Actual Area Prestressed by a Group of Tendons but not less than 12.

K x Area Monitored by a Set of Instruments at a Section (determined as SxL)

For vertical deformations of cylinder, where N=4 S = spacing of tendons in feet (meters)

L = length of a tendon monitored by a set of For radial or sertical deformations of dome, instruments-may be considered as 12 ft(3.66m) and K is determined as follows:

Surface Area of Dome in square feet For containments under uncontrolled env.ranment (square meters)

N=

and having continuous tendon curvature, K 1100 but not less than 4 For containments under uncontrolled environment and hasing essentially straight tendons, K il60 i or containments under controlled environment and hasing either Atraight or cursed tendons.

K 1200 b

126 060 1.90-11

APPENDIX B REFERENCES

1. Jones, K. " Calculation of Stress from Strain in

6. Carlson, R. W., "N1anual for the Use of Stress Concrete ' U.S. Department of Interior, Bureau of Nieters, Strain Nieters, and Joint Nieters in N1 ass Reclamation, Oct. 1961. Copies mas be obtained Concrete." Copies may be obtained from Ter-from the Bureau of Reclamation, Denser Federal rametrics, A Teledyne Company,16027 West 5th Center, Denser Colorad Avenue, Golden, Colorado 80401.

2. Irving, J., " Experience of in-sersice Surseillance

7. Raphael, J. N1., Carlson, R. W. "N!easurement and N1onitoring of Prestressed Concrete Pressure of Structural Action in Dams ' 1965. Copies may be Vessels for Nuclear Reactors," a paper presented at obtained from Terrametrics, A Teledyne Company, International Conference on Experience in the 16027 West 5th Avenue, Golden, Colorado 80401.

Design, Construction and Operation of Prestressed Concrete Pressure Venels and Containments for

8. " Code for Concrete Reactor Vessels and Con-N uclear Reactors, University of York, England, tainments,' American Concrete Institute Committee Sept. 1975. Copies may be obtained from J. C.

359 and American Society of N1echanical Engineers Niundy, Publication Liaison Officer, N1echanical Subcommittee on Nuclear Power,1975. Copies may Engineering Publications Limit:d, P.O. Box 24, be obtained from the American Society of Northgate Avenue, Bury St. Edmunds, Suffolk, N1echanical Engineers, 345 E. 47th St., New Ycrk, IP326 BW.

N.Y.10017 or from the American Concrete Institute, P.O. Box 19150, Redford Station, Detroit, N1ichigan

3. liill, H. T.,

Durchen, N.

B.,

Brittle, W. F.,

48219

" Structural Integrity Test of Prestressed Concrete Containments." a paper presented at International

9. " Guide for Slaking a Condition Survey of Conference on Experience in the Design, Construc-Concrete in Service,' Reported by ACI Committee tion and Operation of Prestressed Concrete Pressure 201. Copics may be obtained from the American Vessels and Containments. U nis ersity of York, Concrete Institute, P.O. Box 19150, Redford Station, England, Sept.1975. Copies may be obtained from J.

Detroit. Niichigan 48219.

C. N1 undy, Publication Liaison Officer, N1echanical Engineering Publications Limited. P.O. Box 24,

10. Whitehurst, E.

A.,

" Evaluation of Concrete Northgate Asenue, Bury St. Edmunds, Suffolk, Properties from Sonic Tests," ACI N1onograph No.

IP326BW.

2. Copies may be obtained from the American Concrete institute, P.O. Box 19150, Redford Station,

4. Brm ne, R D., Bainforth, P. B., Welch, A. K.,

Detroit, Niichigan 48219.

"The Value of Instrumentation in the Assessment of Vessel Performance During Construction and Ser-

11. Leslie, J. R., Cheesman, W. J., "An Ultrasonic dee," a paper presented at International Conference N1ethod of Studying Deterioration and Cracking in on Expert oce in the Design, Construction and Concrete Structures " ACI Journal Proceedings V.

Operr n of Prestressed Concrete Pressure Vessels 46, No.1 Sept.1949. Copies may be obtained from and Containments for Nuclear Reactors, University the American Concrete Institute P.O. Box 19150, of York, England September 1975. Copies may be Redford Station, Detroit N1ichigan 48219.

cotained from J. C. N1unds, Publication Liaison Of-ficer N1echanical Encineer'ine Publications Limited,

12. Van Zelst. T. W.

" Concrete Quality Control P.O. Box 24 Northgate Asen'ue, Bury St. Edmunds, Instruments,' ACI Journal, June 1975. Copies may be obtained from the American Concrete Institute.

Suffolk, IP326BW.

P.O. Box 19150, Redford Station, Detroit, N1ichigan

5. Arthauari, S., Yu, C. W. "An Analysis of the 48219-Creep and Shrinkage Effects Upon Prestressed Concrete N1 embers Under Temperature Gradient

13. " Standard N1ethod of Test for Pulse Velocity and Its Application," Niagazine of Concrete Through Concrete,' ASTN1 Designation C597-71.

Research, Volume 19. N umber 60 Sept.1967. Copies Copies may be obtained from the American Society may be obtained from the Cement and Concrete As-for Testing and N1aterials, 1916 Race Street, sociation, Wexham Springs, SLOUGH SL 3 6 PL.

Philadelphia, Pennsylsama 19103.

9 126 061 1.90- l 2