ML20010C340
| ML20010C340 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 08/13/1981 |
| From: | Herring K Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20010C336 | List: |
| References | |
| NUDOCS 8108190366 | |
| Download: ML20010C340 (7) | |
Text
Enclosure 1 l
b UNITED STATES OF AMERICA I
NUCLEAR REGULATORY COMMISSION-BEFORE THE ATOMIC SAFETY AND LICENSING BOARD -
g In the Matter of Docket Nos. 50-237 COMMONWEALTH EDIS0N COMPANY 50-249 (Dresden Station, Units 2 and 3)
_(Spent Fuel Pool Modifications)
AFFIDAVIT OF KENNETH S. HERRING EVALUATING COMM0fMEALTH EDIS0N'S PROPOSAL TO INSTALL FIVE HIGH DENSITY FUEL STORAGE RACKS I, Kenneth S. Herring, do state as foll,ows:
I am employed by the United States Nuclear Regulatory Commission as a Senior Mechanical Engineer in the Systematic Evaluation Program Branch of the f
DihisionofLicensing. A ~ statement of my professional qualifications is attachedtothisaffidahit.
I hahe rehiewed the information cor,tained in the licensee's submittal, dated August 10, 1981, regarding the structural adequacy of the new racks and pool structures to resist the SSE loads resulting from the installation of fihe new high density spent fuel racks in addition to the existing spent fuel rr's, minus the 13 existing racks which must be remohed to accommodate l
the new racks.
Eyg.UAT_ ION The inital licensee nonlinear analysis evalcations contained in their June 8, 1981 submittal,derised0.76in,ofupliftofthefullrackleg. Later analyses, performed using a slightly different time history in a nonlinear rack analysis, -
which would be expected to yield results comparable to those obtained initially
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i 8108190366 810813 PDR ADOCK 05000237 0
pag.
. i given the dynamic characteristics of the racks, indicated about a 50%
increase in uplift above that initially determined.
In addition, the
" factor of conservatism" given by the licensee for their determination of this value has not been adequately substantiated, considering variations in time histo. ies as input to the nonlinear analyses of racks and variations in the coefficient of friction between the racks and pool floor. Therefore, uncertainty exists regarding the quantification of rack displacements and impact energies derived from the nonlinear analyses which have been performed by the licensee to date.
Previous licensee submittals (see June 8,1981 letter from the licensee to D. Crutchfield, NRC) have demonstrated the capability of the new racks to withstand the impact of adjacent racks and their own impact with the pool wall with substantial margin. Therefore, remaining questions regarding the quantification of uplift and the effects of resulting impacts should not detrimentally affect conclusions regarding the hquacy of the racks in this respect.
The gaps between the pool walls arid existing spent fuel racks, and the proposed five new racks, per an August 11, 1981 telephone conversation with the licensee, are about 32 in, between the west wall and new racks, 28 in. between the new and existing racks, and 8 in, between the north wall and new racks. The gaps between the west wall and existing racks should be sufficient to prelude impact with the new racks, considering the potential uncertainties in the displacements, as discussed above. However, the approximate 8 inch clearance between the north wall and new racks, while
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sufficient to preclude impact for the fully loaded racks, may not be sufficient-to preclude impact for cases where the racks would be partially full of fuel, given the displacements for such cases given in the June 8, 1981 licensee submittal. However, the licensee's evaluation of the full racks impacting wall, contained in this same submittal, demonstrated that the wall could resist impact loads, derived using the energy determined from initial analyses with margin. Since impact energies for the partially loaded cases where impact cannot be precluded will be less than assumed, and a substantial portion of this energy would be absorbed in displacing the racks the several inches needed for impact to occur, the wall capacity should not be exceeded given proper consideration of the uncertainties in the rack displacements.
In addition, the licensee has not demonstrated the adequacy of applying the "Housner Method", Method 1 in its August 10, 1981 submittal,to flexible systems such as the racks and pool structure. Also, the multiple impacts of racks on the slab during a seismic event, and potential further amplifi-cation of the responses computed using the "Housner Method" has not been addressed by the licensee. However, in their August 10, 1981 submittal, by applying Method I! f:;r Une celculation of responses which considered 100% of the energy resulting from 1 inch of uplift of the five fully loaded rack logs to be absorbed by the rack / pool structural system, the licensee demonstrated that margin exists in the racks and pool structure.
Proper consideration of the uncertainties in rack displacements and the calculation of the resulting impact loads should not detrimentally affect,
the conclusions drawn from this analysis regarding the structural integrity of the new racks and pool structures.
Therefore, given:
1.
The margins in the new rscks and pool structures indicated by the licensee analyses performed to date for the five rack installation; and 2.
Consideration of the fact that the Systematic Evaluation Program derived site specific grcund spectra have a substantially lower peak ground acceleration than that assumed in the licensee'stanalyses; I feel that there is reasonable assurance that the structural integrity of the new racks and pool structure will be maintained given the occurrence of a postulated earthquake at the Dresden 2 and 3 sites for the installation of five new hioh density spent fuel storage racks.
CONCLUSION Based on my review of Commonwealth Edison's five rack structural analysis, I conclude that five new spent fuel racks may be safely added to the spent fuel pool at this time. Our review of the 33 rack installation will be completed upon receipt of the additional information requested from Commonwealth Edison.
I swear that the foregoing is true and correct to the best of my knowledge and belief.
A
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na Kenneth S. Herring Systematic Evaluation Program Branch Division of Licensing A
Swor to before me this JS 4
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'l2YIhts.) h YC7 Notary Pu c
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,/T&O My Commission Expires:
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4, PROFESSIONAL QUALIFICATIONS OF KENNETH S. HERRING EDUCATION:
State University of New York at Stony Brook - Bachelor of Engineering -
May 1973:
University of Illinois at Urbana-Champaign - Master of Science in Civil Engineering (Structures) - August 1974:
Continuing Education Courses:
Legal Aspects of Safety, Westinghouse PWR System Fundamentals, BUR-4 System Fundamentals, Teledyne ASME Code Seminar on Code Design of Nuclear Components, MARC Computer Code Users' Course.
ENGINEER-IN-TRAINING:
New Jersey TECHNICAL SOCIETIES:
American Society of Mechanical Engineers - Associate Member - May 1973 to September 1975.
American Society of Civil Engineers - Associate Member - April 1974 to Present.
ASME BOILER AND PRESSURE VESSEL CODE COMMITTEES:
Section XI - Subgroup on Containment - Member - January 1979 to Present.
AWARDS:
U. S. Nuclear Regulatory Commission - High Quality Award - January 1979.
U. S. Nuclear Regulatory Commission - High Quality Award - June 1980.
0 0
Resume 2-Kenneth S. Herring c.
EXPERIENCE:
1 January 1977 to U. S. Nuclear Regulatory Commission i
Present Washington, D. C.
20555 Senior Mechanical Engineer (2/81 to Present)
Sy'stematic Evaluation Program Branch Division of Licensing Office of Nuclear Reactor Regulation Senior Structural Engineer (4/80 to 2/81)
Opera. ting Reactors Assessment Branch Division of Licensing Office of Nuclear Reactor Regulation Senior Structural Engineer (10/79 to 4/80)
Engineering Branch Division of Oper'ating Reactors Office of Nuclear Reactor Regulation Structural Dynamicist (1/79 to 10/79) l Engineering Branch Division of Operating Reactors 1
Office of Nuclear Reactor Regulation Applied Mechanics Engineer (1/77 to 1/79)
Engineering Branch Division of Operating Reactors i
Office of Nuclear Reactor Regulation Responsible for ranaging; coordinating, and conducting the review, the analyses, and the evaluation of structural and mechanical aspects related to safety issues for reactor facilities licensed for power operation, and test reactor facilities, including the formulation of regulations and safety criteria.
An emphasis is placed on seismic, impact and other dynsmic loading considerations, in addition to static loading considerations, and linear and nonlinear, concrete, masonry and steel behavior.
Responsible for managing and coordinating nuclear plant system reviews.
Responsible for managing and coordinating various outside technical assistance contractor programs related to j
nuclear power plant safety issues.
Serve as an expert witness in public' hearing proceedings.
4.
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Resume
. Kenneth S. Herring August 1974 to Stone and Webster Engineering Corporation
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December 1976 3 Executive Campus Cherry Hill, New Jersey Structural Engineer in the Structural Mechanics i
Group.
Responsible for conducting static and dynamic, including seismic,. finite element analyses and design of structures in nuclear power generation facilities.
Responsible for maintaining the Structural Mechanics computer facilities at CHOC.
Fortran IV programming experience.
)
August 1973 to University of Illinois August 1974 Department of Civil Engineering Urbana, Illinois 61801 Research Assistant Responsible for conducting an investigation into the material properties of fiber reinforced concrete using quick-setting cements for the Depcetment of Transportation, Federal Railroad Administration.
PUBLICATIONS:
U. S. Nuclear Regulatory Commission Report, NUREG-0766 entitled,
" Reconnaissance Report:
Effects of November 8,1980 Earthquake on Humboldt Say and, Eureka, California Area," March 1981.
Department of Transportation, Federal Railroad Administration Report, FRA-0RDD 75-7 entitled, " Concrete for Tunnel Liners:
Behavior of i
Steel Fiber Reinforced Concrete Under Combined Loads," August 1974.
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C:mm:nwnith Edison On3 First National Plaza. Chicago, l!!inoh
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Addrtss R ply to: Pcst Ofhce Box 767 Chicago, Illinois 60690 August 10, 1981 Mr. Dennis M. Crutchfield, Chief Operating Reactors Branch 5 U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Dresden Station Units 2 and 3 Seismic Analysis for Installation of Five and Ten High Density Fuel Storage Racks
_NRC Docket Nos._50-237/249 Reference (a):
" Licensing Report Dresden Nuclear Power Plant Units 2 and 3 Spent Fuel Rack Modification",
Rev. 5, dated 1-19-81.
Dear Mr. Crutchfield:
\\
Enclosed for your review are the results of the seismic analyses performed for the installation of five and ten new high density spent fuel storage racks of the type described in Reference (a).
These analyses were performed using the conservative assumptions discussed in the conference call between Commonwealth Edison Company, Quadrex Corp., and the NRC staff on July 24, 1981.
As discussed previously, interim installation of five or ten new fuel storage racks in the Dresden 3 fuel pool will preclude the need to transfer fuel in fuel shipping casks from the Dresden 3 fuel pool to the Dresden 2 fuel pool in order to support the January 1982 Dresden 3 refueling outage.
The fuel transfers would be necessary to maintain the ability to unload the core to facilitate NRC required modifications to the feedwater spargers.
The five or ten new racks will provide the additional spaces necessary to accomplish core unloading without fuel transfers.
Please address any questions concerning this matter to this office.
g x0D
D. M. Crutchfield August 10, 1981 One (1) signed original and thirty-nine (39) copies of this transmittal are provided for your use.
Very truly yours, f
-uwA b(J.Rausch T.
Nuclear Licensing Administrator Boiling Water Reactors cc:
Region III Inspector, Dresden Mr. John Wolfe, Esq.
Dr. Linda W. Little Dr. Forest J. Renwick Ms. Mary Jo Murray l
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4 Dresden Nuc_ lear _ Station Evaluation of Spent Fuel Pool and Racks for Five and Ten Racks Impacting on Pool Floor
1.0 INTRODUCTION
It has been proposed that existing spent fuel racks at the north end of the Dresden 3 pool be replaced with 5 or 10 new high-density fuel racks.
The scope of the present evaluation is to determine whether the spent fuel pool floor and walls can withstand the additional loads resulting from rocking of the racks during a postulated safe shutdown earthquake.
In the absence of nonlinear rocking and sliding analysis for the loaded rack, the magnitude of the maximum uplift was computed earlier using an energy-balance method based on the maximum sliding velocity of an empty rack.
This uplift value was computed to be 0.76 inch.
However, for the present evaluation to be conservative, this uplift value was arbitrarily increased to 1.0 inch.
The existing racks are bolted to the floor, hence, no uplift of these racks was considered.
1-1 2392N
2.0 ANALYSIS AND EVALUATION OF POOL SLAB An energy-balance pathod'of analysis was used for evaluating the loads on the pool floor. To determine en upperbound of this load, it was as-suced that the entire energy resulting from impact will be absorbed by the strain energy of the pool floor and the irpacting rack in a single impact.
In other words, the energy that would be left in the rack which would cause it to rebound and rock was not subtracted to compute the energy that needs to be absorbed in the pool floor.
2.1 Inpu_t Kinetic Energy For 1-inch uplift, the angular velocity of the rack was computed to be 0.177 radian per sec.
This was detemined by equating the restoring morent of the tilted rack to the product of its morant of inertia and angular acceleration and solving the equation of mtion.
This nethod of computing the angular velocity, outlined in Reference I,uses the rack geccetry, mass and the uplift value and assuvs realistically that the rack behaves as a rigid body while dropping from the tilted position.
The vertical impact velocity at the uplifted end of the tack, computed froa this angular velocity, was 10.02 in/sec. The velocity of different parts would vary between this maximum value and zero (at the pivoting end).
The kinetic energy of impact was calculated using linear velocity distribution. This rathod of characterizing t.he motion of a tilted structure has been experirentally verified in Reference 2 and is considered a more accurate representation of the actual phencoena as co pared to the alternate method described in the next paragraph.
This nethod is desig-nated as Method I.
An alternative method #ethod II) of computing the kinetic energy was also investigated.
In this alternative rethod, the rack was idealized as a beam having a length equal to the width of the rack.
The depth of the beam was ignored. The tip of the beam was assumed to be uplifted by 1.0 inch and allowed to be dropped.
The velocity of the rack at the up-lifted 'end was cor:puted assuming a free-fall, i.e., velocity equal to.
hwhere g is acceleration due to gravity and h is the drop height (i.e.,
1.0 inch). Using the uplifted-end velocity (27.8 in/sec.) and a linear velocity distribution, the i= pact energy was conrputed by integrating 2-1
)
over the length of the idealized beam. The peak velocity cog uted this way assumed a free drop and is not an accurate representation since the rack does not fall freely, rather rotates pivoting about the other leg.
Thus, the phenccenon assumed in inis Method 11 analysis is not considered o a true representation of the actual situation, even though, for the pur-pose of comparison, the pool structures have been evaluated using the input kinetic energy values obtained by both methods.
2.2 Encray Absorbing Chare _cterist_i_cs of the Pool Slab Impact energy is dissipated in the pool slab in three ways:
a) Inertia of the pool slab to movement b) Strain energy resulting from the lo:al ccepression of the con-crete underneath the rack legs c) Strain energy resulting % the overall behavior of the floor slab acting as a plate Since the weight of the supporting pool floor target mass is relatively high, some of the applied energy will be absorbed because of the inertia of the t u ber to movement. The target mass was assur.ed to be equal to the nsss of that portion of concrete pool slab which is contained in the volume bounded by 45-degree inclined planes from the edge of the rack leg and the bottom surface of the pool slab (Reference 3) as shown in Figure 2-1.
For cogating the maximum rack load and the concrete bearing stress, energy absorption due to inertia of the target mass was not con-sidered.
Strain energy resulting from the local compression of the concrete under-neath the rack leg was computed assuming a nonlinear distribution of com-pressive stress under the rack leg as shown in figure 2-2.
The compmssive stress at the interface is equal to the bearing stress and, at the bottom surface, this stress is zero.
The variation of this stress across the depth was assumed to be parabolic in cor@uting the equivalent linear spring to represent the local energy absorbing characteristics of the slab.
2-2
Strain energy resulting from the overall behavior of the floor slab acting as a plate would depend upon the location of the 1%act.
For the five-rack igact, two such locations were considered:
a) tecetion A, cornsponding to rack legs close to the north wall of the pool, and b) location B, corresponding to rack legs away from the wall.
Location A is only 9 inches from the wall. Hence, it was assmed that the energy dissipation resulting from the overall plate-type behavior of the floor would be small and negligible when the rack legs impact in Location A.
Location B is about 5.5 ft. from the wall.
Energy absorp-tion characteristics for impact at this location were represented by a linear spring, properties of which were cogated from the bending be-
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havior of the slab. Tie inoment of inertia of the slab cross-section was computed using the fonnula in ASCE Standard Manual 58 (Reference 4).
This fonsla provided a noment of inertia larger than that obtained from ACI-118-77 code _(Reference 5) (correspeding to actual morent re-sulting from a floor load which produces shear equal to the shear capac-ity of the slab). Thus, the use of this fonnula is considered conservative.
For the ten rack case, the tacks impact along two parallel line's:
Legs nearest the north wall and legs farthest from the north wall (two parallel rows of 5 racks each).
The analysis utilized the same methodology described above and the results reported in Table 2-2a are for impact of the legs nearest the wall which generates the highest lead at the support and at a distance, d, from the support.
2.3 Energy Absorbing Characteristics of the Rack When the racks impact on the pool floor, a part of the impact energy will be absorbed in the form of strain energy of the rack. This energy absorp-tion characteristic was represented by a linear spring constant.
This linear spring constant was derived using the vertical stiffness and de-flection characteristics of the detailed finite elecent model of toe ' rack which was originally used for c'ead load stress analysis.
2-3
2.4~ Analysis Results and Evaluation of Pool Slab Using the energy balance method described above, the rack impact load on the pool floor was computed. The computed dynamic amplification factors are listed in Table 2-1.
Combining the rack impact load with the dead loads and hydrcse. tic loads and vertical seismic loads, and assuming very
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conservatively that all the racks impact simalteneously, the sheaFload in' M'~
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the pool slab was coeputed and _ compared wtth the.a'llowabic values. Thes
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are listed in Tables 2-2 and 2-2a, for five and ten racks, respectively.
Shear loads were computed at the floor support location (Location A)~as well as at a distance d (equal to depth of the slab) from the support (Location B).
Comparison of the computed shear loads with the allowable values shows that the pool slab can adequately withstand the total loads, including the impact loads resulting from 1-inch uplift of the loaded racks.
2-4
Target Mass (shaded)
R k Leg ---
F
- Pool Slab JA i/
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2 m,i I N/
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45" i
FIGUPE 2-1 TARGET MASS UNDER FACK LEG l
Pack Leg Pool Slab--
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b Parabolic Distribution of Compressive Stress I
FIGURE 2-2 ASSUMED DISTRIBUTION OF COMPRESSIVE STRESS UNDER PACK LEG
TABLE 2-1 OYNA5f!C AMPl.IFICATION FACTORSII}
RESULTING FROM RACK IP. PACT Location of Drop
/A B
Method I 6~5 6.1 Method II If3.1 17.1 NOTEIII: Dynamic Amplification factor is defined as the ratio of rack leg force during rack fr. pact to the rack leg force due to buoyant weight of the rack applied as a static load.
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TABLE 2-2 POOL SLAS ANALYSIS RESULTS FOR FIVE-RACK IMPACT Estimated Upperbound Uplift = 0.75 in.
Assur.ed Uplift = 1.0 in.
Maxicum Impact Yelocity--
Method I : Based on k. gular Velocity = 10.02 in/sec Method II: B2 sed on Free Fall = 27.8 in/sec (See Note 4 below)
Equivalent Unifom Dead Load Without Impact--
5 New Racks + Old Racks = 0.86K/ft2 Total (including seismic) = 4.99K/ft2 Shear Lead (Kip /ft) Using Method 1(II Location OI At Support At Distance d From Support Drop Co puted Allowable Computed Allowable A
65.5 522.Z(2)
<40.1 82.6I3) 8
<65.5 522.2(2)
<40.1 82.6(3)
NOTES:
(1) Average shear load at the north end of the pool ficar (2) Based on Scction 11.7.3 of Reference 5 (Shear Friction)
(3) Based on Section 11.3.1.1 of Reference 5 (i.e., the short somula)
(4) Computed for the purpose of comparison only 4
2-7
TABLE 2-2(continued)
POOL SLAS ANALYSIS RESULTS FOR FIVE-RACK IMPACT Shear load (Kip /ft) Using Method 11(4)(1) '
Location i
0 At Support At Distance d Fro:a Support l Drop g
Computed Allowable l Computed Allowable f
82.6(3I A
129.0 522.2(2) do.1 B
<129.0 522.2(2) 40.1 62.GI
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NOTES:
(1) Average shear load at tha north end of the pool floor (2) Based on Section 11.7.3 of Reference 5 (Shear Friction)
(3) Based on Section 11.3.1.1 of Reference 5 (i.e., the short fomula)
(4) Computed for the purpose of comparison only 2-8
Table 2-2a Pool Slab Analysis Results for Ten-Rack Impact Equivalent Uniform Dead Load Without Impact--
2 10 New Racks + Old Racks = 0.98 k/ft 2
Total (including seismic) = 5.13 k/f t Shear Load (Lip /ft)
At Distance d From Support Methcd At Support
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.a Computed Allowable Computed Allouable 54)
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522.2(2) 52.5 82.6 Method 84,1 1
85.1 I3 I2) 87.2 90.8 Metho6 179.2 522.2 II
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(1) Average shear load at north end of the pool floor.
NOTES:
(2) Based on Section 11.7.3 of Reference 5 (shear frictio (3) Computed for the purpose of comparison only.
(4) Based on Section 11.3.1.1 of ttererence 5.-
(5) Based on Section 11.3.2.1'of Referene-
).
5 with f' (6) Based on Section 11.3.2.1' of i-i C
increased by 15% due to aging.
1 i
3.0 EVALUATION OF RACK STRESSES Table 3-1 presents the auxirma loads on rack legs when the impact force l
resulting from I-inch uplift is considered. These are based on impact at Location A, which gives the most critical rack loads. Also, the effect of energy dissipation in target mass inertia was ignored to neximize these rack loads, and no everall pool slab flexibil.ity was considered.
Table 3-1 also presents the rack leads from the original fixed-base analysis for the purpose of comparison. Table 3-2 lists the stresses in various critical components of the racks when the effect of impact resulting from 1-inch uplift is included.
Comparison of these stresses with the allowable stresses shows that the rack design is ade-quate and no overstress condition is expected.
t, 9
3-1
--- 1--- 1-- - _ -
TABLE 3-1 MAXIWJM RACK LEG FORCES DUE TO PACK IM?ACT ON FOOL SLAS Maxirnua Force (kips)
Consideration g g(1)
Corner Lc; Middle leg Corner Leg I'iddleLeg Considering Rack 92.3 115.4 256.2 320.2 Imptet Near k'all Original fixedAase 179.8 203.9 179.8 203.9 Analysis Nate: (1) Computed for the purpose of comparison only.
9
d TABLE 3-2 STRESS IN PACK C0.".PO!iEfCSD'JE TO RACK IMPACT ON POOL SLAB (3)
Computed Rack Load Critical Allowable (2)
Stress (ksil Component Combination Stress Type Stress (ksi)
Method I Eethod N 0)
Tube k'all D+B+E' Membrane 33.5 11.53 31.98 Support D+B+E' Membrane 33.5 9.28 25.74 Filier Plateg MB+E' Membrane 33.5 9.19 25.49 Base Grid M +E' F.embrane 33.5 1.70 4.70 Rack Leg MB+E' Membrane 33.5 8.55 23.71 Interface D+B+E' Bearing 4.76 0.87 2.42 Hote:
(1) Computed for the purpose of comparison only.
(?) Using a Dynamic Increase factor of 1.2 per Reference 4.
(3) Deceleration loads resulting from irrpact are maxirc;= at the uplifted end (i.e., the impacted end) and zero at the pivoted end. The rack !vg re-action forces shmen in Table. 3-1 are for the impacted legs, and st are based on maxist.= deceleration values. Thus, the ratio between these reaction forces to the dead load reaction forces oives the conservative scaling factor with which the dead Icad stresses {from original finite elerant analysis) were multiplied to obtain the stresses in the rack for impact loads shown in this table.
O
4,0 EVALUATION OF NORTH WAL'L Because of its proximity to the impacting racks, the north wall of the pool will have loads higher then the other walls.
This wall was ev aluated f or the combir ed load (SSE load case) including the effect of five new racks impacting on the pool floor.
Table 4-1 presents the comparison of the shear capacity with the computed shear loads based on impact at the critical Location A, for the five rack case.
Table 4-la presents the comparison of the shear capacity with the computed shear loads based on impact of the legs nearest the North wall, which is limiting, for the ten rack case.
Results presented in Tables 4-1 and 4-la show that the computed values are well within the shear capacity of the wall for both the five and ten rack cases.
i 4-1 2392N I
M TABLE 4-1 EVALUATIOi 0F TF.E VERTICAL SilEAR CAPACITY OF THE NORTH HALL (3)
Vertical Shear (kips)
Load Combination Computed Method 1 Method 11()
j D+L+H+E'+ Impact 15,724(2) 4607 3374 Note:
(1) Cc:puted for the purpose of co:Garison only.
(2) Considering the effect of vertical reinforcement in resisting diagonal tension resulting from shear, (3) Based on the critical impact Location A.
4-2
Table 4-la EVALUATION OF THE VERTICAL SHEAR CAPACITY OF THE NORTH WALL (3)
Vertical Shear (kips)
Load Combination Allowable Method 1 Method II(1)
D+L+H+E'+ Impact 13,600(2) 4,270 5,811 Note:
(1)
Comouted for the purpose of comparison only.
(2)
Considering the effect of vertical reinforcement in resisting diagonal tension resulting from shear.
(3)
Based on impact of legs nearest !! orth wall.
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l 5.0 REFEREi(CES 1.
Housner, G. W., "The Behavior of Inverted Fentulu a Structures during Earthquakes," Bulletin of Seisnological Society of Awrica, Vol. 53, No. 2, February,1963.
2.
Aslam, M., Godden, W. G., and Scalise, " Earthquake Rocking Response' of Rigid Bodies," J. of Structural Divisicn, ASCE. February,1950.
3.
Topical Report, " Design of Structures for Missile Impact," BC-TOP-9A, Revision 2, Ecchtel Power Corporation,1974.
4.
ASCE P.anual and Report on Engineering Practice fio. 5B, " Structural Analysis and Design of fluclear Plant Facilities," 1980.'
5.
" Building Code Requirsents for Reinforced Concrete," ACI-318-77, A erican Concrete Institute,1977.
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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
)
)
COMMONWEALTH EDIS0N COMPANY
)
Docket Nos. 50-237
)
50-249 (Dresden Station, Units 2 and 3)
)
(Spent Fuel Pool Modification)
CERTIFICATE OF SERVICE I hereby certify that copics of NRC STAFF RESPONSE TO APPLICANT'S MOTION EOR A PARTIAL INITIAL DECISION in the above-captioned proceeding have been served on the following by deposit in the United States mail, first class or, as indicated by an asterisk, through deposit in the Nuclear Regulatory Commission's internal mail system, this 13th day of August, 1981.
John F. Wolf, Esq., Chai. man Mary Jo Murray. Esq.
Administrative Judge Assistant Attorney General 3409 Shepherd Street Environmental Control Division Chevy Chase, Maryland 20015 188 West Randolph Street, Suite 2315 Chicago, Ill. 60601 Dr. Linda W..Little Administrative Judge Atomic Safety and Licensing Board Panel 5000 Hermitage Drive U.S. Nuclear Regulatory Commission Raleigh, North Carolina 27612 Washington, D. C. 20555
- Dr. Forrest J. Remick Atomic Safety and Licensing Appeal Administrative Judge Board Panel 305 E. Hamilton Avenue U.S. Nuclear Regulatory Conmission State College, PA 16801 Washington, D. C. 20555
- Philip P. Steptoe, Esq.
Docketing and Service Section Isham, Lincoln and Beale U.S. Nuclear Regulatory Commission One First National Plaza Washington, D. C. 20555
j Safety d'
1035 Outer Park Drive, 5th Floor Springfield, Illinois 62704 liichard J. Ecddard l
Counsel for NRC Staff I
1