ML20010H607

Forwards Request for Addl Info Re Structural Engineering. Info Should Be Submitted by 811030

ML20010H607
Person / Time
Site:	Perry
Issue date:	09/16/1981
From:	Houston M Office of Nuclear Reactor Regulation
To:	Davidson D CLEVELAND ELECTRIC ILLUMINATING CO.
References
NUDOCS 8109280205
Download: ML20010H607 (30)

Text

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SEP 161981

.!Qf, Docket lios. 50-440 and 50-441 t,

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l 11r. Dalwyn R. Davidson g

1. j a Vice President - Engineerir.g Cleveland Electric Illuminating pg#

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Company P. O. Box 5000 s

Cleveland, Ohio 44101

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Subject:

Request For Additional Information - Structural Engineering In the performance of the Perry licensing review, the staff has identified concerns in regard to structural engineering. The information that we require is identified in the enclosure.

lie request that you provide the information not later than October 30, 1931.

If you require any clarification of this request, please contact as at (301) '92-8593.

Sincerely,

11. Dean llouston, Project lianager Licensing Branch flo. 2

~ Division of Licensing

Enclosure:

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Mr. Dalwyn R. Davidssn Vice President, Engineering The Cleveland Electric Illuminating Company P. O. Box 5000 Cleveland, Ohio 44101 cc: Gerald Charnoff, Esq.

Shaw, Pittman, Potts & Trowbridge 1800 M Street, N. W.

Washington, D. C. 20006 Donald H. Hauser. Esq.

The Cleveland Electric Illuminating Company P. O. Box 5000 c

Cleveland, Ohio 44101 Resident Inspector's Office U.S.N.R.C.

Parmly at Center Road Perry, Ohio 44081 Donald T. Ezzone, Esq.

Assistant Prosecuting Attorney 105 Main Street Lake County Adninistration Center Painesville, Ohio 44077 Tod J. Kenney 228 South College, Apt. A Bowling Green, Ohio 43402 Daniel D. Wilt Wegman, Hesiler & Vanderberg 7301 Chippewa Road, Suite 102

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Brecksville, Ohio 44141 Robert Alexander OCRE Interim Representative 2030 Portsmouth Street Suite 2 Houston Texas 77098 Terry Lodge, Esq.

915 Spitzer Building Toledo, Ohio 43604

REQUEST FOR ADDITIONAL INFORMATION STRUCTURAL ENGINEERING BRANCH PERRY NUCLEAR POWER PLANT UNITS 1 AND 2 DOCKET NUMBERS:

50-440/441 220.06 Provide prccedures by which venting, if considered, is used (3.3.2) to reduce the tornado vacuum in your Category I structural design.

220.07 In your barrier design procedures there is not enough information (3.5.3) in the evaluation of overall response of structural elements subjected to impactive or impulsive load, such as impacts due to missiles. A copy of the draft Appendix A to Standard Review Plan (SRP) Section 3.5.3 is attached herewith for your reference (Attachment 1).

Please take notice of the staff position on the acceptable ductility ratios for reinforced concrete and structural steel elements subjected to impactive and impulsive loads, i

Express your intention to comply with this staff position.

220.08 You stated that for the dynamic analysis used in this plant, (3.7.1) the hysteretic damping in combination with small percentage theoretical viscous damping is used as a conservative approach.

Please explain in detail and discuss the technical basis for the assessment of the conservatism of the approach.

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l Page 2 Request for Additional Information 220.09 Demonstrate that the frequency intervals at which spectra S

(3.7.1) values are calculated from the design time history are smal enough that any reduction in these intervals does not result in more than 10% change in the computed values.

220.10 With regard to the issue of interaction of non-Category I (3.7.1) structures with seismic Category I structures, discuss the basis for the selection of the three inches structural gap.

Also list the analytical results (displacement) and demonstrate that adequate separation among structures has been provided.

i 220.11 With respect to FSAR Section 3.7.2.1 seismic analysis method, (3.7.2) you didn't state clearly how many significant modes were included in the modal analysis.

It is the staff's position that a sufficient number of modes should be considered; tne-criterion for sufficiency is that the inclusion of additional modes does not result in more than 10% increase in response.

Please indicate vour compliance with this position or justify any deviation from the position.

220.12 With respect to Section 3.7.2.4 soil-structure interaction (3.7.2) analysis for diesel generator building and off-gas building, you stated that finite elercent method was used.

It is the staff's position that modeling methods for implementing the soil-structure interaction analysis should include both the half-space and finite element approaches. Category I g^

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structures, systems and components supported on soil should be designed to accommodate responses obtained by nne of the following:

(a) envelope of results of the two methods, (b) results of one method with conservative design considerations of effects from use of the other method, and (c) combination of (a) and (b) with provision of adequate conservatism in design.

Expruss your intention to comply with this staff position.

220.13 With respect to FSAR Section 3.7.3.9.1 you stated that (3.7.3) equipment supported at different locations is analyzed by imposing a single conservative response spectrum at each location, this response spectrum is considered in such a way that it conservatively envelopes the pertinent response spectra of the different locations. Please provide more details and give an example of how the relative displacement between supports are generated and used in the static analysis of systems with differential support motion.

i 220.14 With respect to FSAR Table 3.8.1, please provide in a tabular (3.8.1) format the design moments, shears and the required reinforcements corresponding to various governing load combinations for:

(1) Shield building cylinder wall ring girder at the junction of dome.

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(2) Shield building cylinder wall at the junction of foundatior.

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Page 4 Request for Additional Information 220.15 With respect to FSAR Section 3.8.1.1, description of-the (3.8.1) containment (shielding building, p. 3.8-4) you stated that typical details of the cylinder wall foundation mat junction are shown in Figure 3.8.-3.

The title and content of Figure 3.8.-3 show the typical reinforced section for the shield building wall and dome. Please correct the discrepancy.

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220.16 With reference to FSAR Section 3.8.1.2, 3.8.3.2, 3.8.4.2 and (3.8.1, 3.8.5.2, applicable codes, standards and specifications, 3.8.3 it is the staff's position that ACI 349-76 Code should be 3.8.4 and ased in conjunction with Regula tory Guide (R.G. ). l.142.

i 3.8.5)

Identify deviations of Categary I structural desigr.

from the requirements of the code and the Regulatory Guide and justify your deviations.

220.17 With respect to FSAR Table 3.8.2, provide in a tabular format (3.8.2) the stresses corresponding to various governing loading combinations fcr the steel vessel at key locations, such as:

(1) At the junction of steel shell and foundation mat.

(2) At the junction of steel shell and dome.

(1) At the junction of steel shell and polar crane support.

Also show that the design stresses at these points comply with the requirements of the ASME Section III, Division I Code.

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~ 220.18; With respect to FSAR Section 3.8.2.4, design and analysis

. (3.8.2) procedures, you stated'that' the buckling investigation of the containment vessel cylinder consists _of two approaches.

First the shell and stiffeners are verified to be in compliance with all the requirements of subsection NE-3133 of' ASME Code,'Section III and secondly, a detailed buckling j

analysis is performed using equations from " Structural Analysis of ShelL".

Please indicate:

1 (1).Your rationale'for using the method of analysis from reference 9, of Section 3.8 of FSAR.

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(2) The loads and load combinations that have the potential of buckling the containment vessel and how each load or load combination is applied to the vessel. The method given in Section 5 of the NUREG/CR 0793 report

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" Buckling Criteria and Application of Criteria to s<

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or problems which you may encounter in using the method.

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A comparison between the method that you used and the'.

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I indicate that your method is conservative.

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220.1 9 Provide a containment capacity analysis of the steel containment

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' (~1.8.2) responding to the internal pressure build up due to hydrogen s

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burning. The guideline and staff position on this subject is

. enclosed (Attachment 2).-

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1 Page 6 Request for Additional Information 220.20 With reference to the issue of fluid / structure interaction, (3.8.2) you stated, in Section 2.1.4, Appendix 3A of FSAR, that for (3.8.3) fluid modeiing three different modeling techniques were used to represent the water, and AN5YS Computer Program was used for all three anal,rses.

You concluded the concentrated mass method adequately represented the fluid and is used in the reactor building analysis.

Discuss in detail of your technical basis for the conclusion and provide the results of the hydrodynamic loads analysis.

220.21 With respect to the loads and load combinations for steel (3.8.2) containment vessel (Section 3.8.2.3), steel and concrete (3.8.3) internal structures (Section 3.8.3.3), a load summation method for static and dynamic loads due to pool swell and safety relief valve discharge is recommended in Section 3BA.8.4, Appendix 3B of FSAR.

Discuss the relative degree of con-servatism between the use of the absolute sum method and that of the AC/DC method proposed.

For your information, presently, the absolute sum method (ABS) of combining dynamic loads is acceptable to the staff.

220.22 (1) Provide the analysis details of the lower region of (3.8.3) drywell wall with regard to transfer of shear force to the foundation mat and the anchorage provision for 1

uplift force.

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JPAge'7RequestforAdditionalInformation (2) Provide design details for the drywell wall at main

-steam line whip restrains.

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220.23'[

With respect to FSAR Section 3.8.4.4 Design Methods of x, s, (3.8.3)

Drywell. Wall, you stated that the drywell wall diagonal l'

reinforcement was designed to the criteria for tangential shear requirement of ASME Code,Section III, Division 2.

Provide design and analysis details to support your statement.

Refer to SRP Section 3.8.1, II-4 for the exceptions taken J

by the staff, indicate your compliance with the staff's position, or justify any deviation from the position.

220.24 With respect to FSAR Section 3.8.4.1.3, Fuel Handling Building, (3.8.4) discuss, in detail, the design of spent fuel pool racks.

Enclosed is a copy of staff position on "The minimum requirements for design of spent fuel pool racks" (Attachment 3). Modify your analysis and design, if necessary, to agree with this position.

220.25 (1) With respect to the design and analysis of reactor (3.8.5) building mat, please provide your analysis results such as the design moments and shears for the foundation mat at various critical sections.

Provide a detailed discussion of how these mcments and shears are acconmodated in the design.

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.'Page 8 Request for Additional Information

'.(2)' Provide design calculations of reactor building foundation mat reinforcement at the junction of:

(a) Concrete shield building wall; (b) Drywell wall; and (c) Reactor pressure vessel pedestal wall.

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,(3) Demonstrate that applicable code provisions are fully l-

'.. -met in your design.

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, PEovide detail' stability =.alysis of Category I structures

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<and demonstrate that the factors of safety against floating,

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sliding and overturning as shown in SRP Section 3.8.5 II-5 6, t 'O

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220.27 '

With respect to FSAR Section 3.8.5.1, you stated that where

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- possible shear transfer from the bearing material to the 1-l

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reinforced concrete foundation is by frictions, otherwise shear transfer is by a combination of friction and passive soil pressure against shear keys.

Provide the shear key design analysis for auxiliary building, fuel handling

. building, control building, intermediate building and the off-gas building.

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'Page' 9 Request for Additio al I fn ormation n

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220.28' With respect to FSAR Section 3.8.5.5,

p. 3.8-209 the expression (3.8.5)-

3pf'cshouldbe3%/f'cpleasecorrecttheerror.

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--220.29' Prepare for the structural design audit scheduled for the week N'k

.of November 23, 1981. A copy of requirements for implementation ~

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'of structural design audits is enclosed'(Attachment 4).

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- he audit meeting in order to expedite the audit work.

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ATTACK"ENT 1

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APPENDIX A TO SRP SECTION 3.5.3 ALLOWABLE DUCTIILITY RATIO FOR OVERALL DAMAGE PREDICTION I.

INTRODUCTION In the evaluation of overall response of reinforced concrete structural elements (e.g., missile barriers, columns, slabs, ets.) subjected to impactive or impulsive loads, such as impacts due to, missiles, assump-tion on non-linear response (i.e. ductility ratios-greater than unity) of the structural elements is generally acceptable provided that the intended safety functions of the structural elements and those of safety-related systems and components supported or protected by the elements are maintained. The following summarizes specific positions and rev'.sw and acceptance of dactility ratios for reinforced concrete and stee? structural elements subjected to impactive and impulsive loads.

II.

SPECIFIC POSITIONS

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1.

REINFORCED CONCRETE MEMBERS For beams, slabs, and walls where flexure controls design, the a.

permissible ductility ratio under impactive and impulsive loads should be taken as 0.05 < 10 where p and p' are the ratios of p-p tensile and compressive reinforcing as defined in ACI 349-76 Code.

b.

If use of ductility ratio greater than 10 (i.e.,u > 10) is re-quired to demonstrate design adequacy of structural elements against impactive or implusive loads, e.g., missile impact, such

a Pag 2 2 of Attachment 1 as usage should be identified and justified by submittal of q ':

applicable experimental evidence in the plant SAR.

For bean-columns, walls, and slabs carrying axial compression c.

loads and subject to impactive loads (e.g., missile imptet) producing flexure, the permissible ductility ratio in flexure should be as follows:

(i)

When compression controls the design, as defined by an interaction diagram, the permissible ductility ratiou should be !.3.

as (ii)

When the ;ompression load does not exceed 0.lf'cAg or one-third of that which would produce balanced conditions, whichever is smaller, the permissible ductility ratiou should be as given in 1.a.

(iii) The permissible ductility ratioshould vary linearly from 1.3 to that given in 1.a for conditions between those specified in (1) and (ii) (see Fig.1).

d.

For beam-columns, walli, and slabs, carrying axial compression loads subject to implusive loads (e.g., compartrent pressuri-zation) producing flexure, the permissible ductility ratio u in i

flexure should be 1.0.

For structural elements resisting axial compressive impulsive or e.

impactive loads only, without flexure, the permissible axial ductility ratio y should be 1.3.

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For-shear _ carried by coricrete only p= 1.0 For shear carried by concrete and stirrups or bent bars u= 1.3 For shear carried entirely be stirrups y= 3.0 T2. STRUCTURAL STEEL MEMBERS a.

For tension due to flexure p = 10.

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For columns with slenderness ratio ( 1/r) equal or less than 20 u= 1.3

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Where 1 = effective length of the member j_

r = the least radius of gyration I

For columns with slenderness ratio greater than 20 l

k= 1.0 c.

For members subjected to tension V= 0.5 Eu l

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Where cu = ultimate strain cy = yield strain

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ATTACHMENT 2

.s CAPACITYiASSESSMENT OF STEEL CONTAINMENT The analysis should be performed to provide a reasonable assurance that the integrity of the containment will be maintained during an accident that re-

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leases hydrogen generated from -75% fuel clad metal-water reaction accompanied by either hydrogen burning or the added pressure from post-accident inerting assuming carbon dioxide is the inerting agent, depending upon which option is chosed for control of hydrogen.

As a criterion of such an assurance, it should be demonstrated through an analysis that in case of an accident described above, the requirements of the ASME Boiler and Pressure Vessel Code, Division 1, (Code) Subsubarticle NE-3220, Service level C Limits, considering pressure and dead load alone, will be met.

As a minimum, the code requirements set above should be met for a combination of dead load and an internal pressure of 45 psig.

If the option chosen for hydrogen control is post-accident inerting, the fol-lowing must be demonstrated hy the analysis:

(a) Containment structure loading produced by an inadvertent fu'l inerting (assuming carbon dioxide), but not including seismic or design basis accident loading will not produce stresses in steel concainment in ex-cess of the limits set forth in the ASME Boiler and Pressure Vessel Code, Division 1, Subsubarticle NE-3220, Service level A Limits, except that evaluation of instability is not required.

Page 2 Ef Attachment 2 (b)L A pressure test, which is. required, of the containments 1.10 times the pressure calculated to result from carbon dioxide inerting can be safely conducted, and, (c) In advertent full inerting of the containment can be safely accommo-

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' dated during plant operation.

In order to be acceptable, the analysis used for determination of ultimate capacity of.the containment should be based on the general principles of

. structural mechanics and consistent with sound engineering practices. The model 'used in the analysis should be realistic representation of the con-tainment r.ructure.

The pressure capacity. of localized areas as well as of the overall contain-

- ment structure thould be examined for the static and-dynamic pressures re-

-spectively; The staticLand @namic pressures to be used in the analysis

.should be approved by the Containment Systems Branch.

The analysis should be made on the basis of the allowables specified in the Code. However, if the actual material properties, such as the tested s

material strength, strength variations indicatd by mill test certificates and other material uncertainities are available, the lower and upper bounds of the containment capacity may be established statistically. The details of Lthe analysis and the results should be submitted in a report form with the following identifiable information.

1. iThe original design pressure, Pa, as defined in the Code, Subsubarticle

-NE-3220;-

.2. fCalculated static pressure capacity;

Page 3 cf' A'ttachment 2 13.

Equivalent static pressure responsc calculated from dynamic pressure; 4.

The' associated failure mode; 5.

The criteria ' governing the original design and the criteria used to

' establish failure; 6., Analysis details and general results; and, 7.

Appropriate engineering drawings adequate to allow verification of

- modeling and evaluation of analyses employed for the containment

- structure.

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APPENDIX D TO SRP SECTION 3.8.4

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MINIMUM REQUIREMENTS FOR DESIGN OF SPENT FUEL POOL RACKS INTRODUCTION The purpose 07 thi appendix is to provide the minimum requirements and criteria for review of spent fuel pool racks.

The criteria fcr the structural design of the spent fuel pool proper are contained in the main body o# this section.

This appendix describes the acceptable criteria of the spent fuel pool structure as it relates to the racks.

(1) Description of the Spent Fuel Pool and Racks Descriptive information including plans and sections showing the spent fuel pool in relation to other plant structures shall be provided in order to de-fine the primary structural aspects and elements relied upon to perform the

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safety-related functions of the pool, spent fue1 pool liner and the racks.

The main Safety function of the spent fuel pool, the liner and the racks is to maintain the spent fuel assemblies in a safe configuration through all environmental and abnormal loadings, such as earthquake, and impact due to spent fuel cask drop, drop of a spent fuel assembly or drop of any other heavy object during routine spent fuel handling.

The major structural elements reviewed and the extent of the descriptive information required are indicated below.

(a) Support of the Spent Fuel Racks:

The general arrangements and prin-cipal features of '.he horizontal and the vertical supports to the spent fuel racks should be provided indicating the methods of transferring r'

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LPage 2 of Attachment 3 "the loads on the racks to the fuel pool wall and the foundation slab.

All gaps-(clearance or expansion allowance) and sliding contacts should be indicated. The extent of interfacing between the new rack system end the old fuel pool walls and base slab should be discussed, i.e.,

interface loads, response spectra, etc.

.If connections of the racks are made to the base and to the side walls of the pool such that the pool liner may be perforated, the provisions for avoiding leakage of radioactive water of the pool should be indi-cated.

(b) Fuel Handling: Postulation of a drop accident, and quantification of j

the drop parameters are reviewed by the Accident Evaluation Branch (AEB). Structural Engineering Branch accepts the findings of the AEB s

review for the purpose of review of integrity of the racks and the fuel pool including the fuel pool liner due to a postulated fuel handling accfdent.

Sketches and sufficient details of the fuel handling system should be ; ovided to facilitate this review.

(2) Applicable Codes, Standards and Specifications Construction-materials should conform to Section III, Subsection NF or Reference 3.1.

All materials should be selected to be compatible with the fuel pool environment to minimize corrosion and galvanic effects.

Design, fabrication, and installation of spent fuel racks of stainless steel material may be performed based upon Subsection NF requirements of Reference 3.1 for Class 3 component supports.

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Seismic and Impact Loads i

For ~ plants where dynamic input data such as floor response spectra or ground response spectra are not available, nect sary dynamic analyses may be per-formed using'the cr;teria described in section 3.7 of this plan. The ground response spectra and damping values should corresp,ond to R. G.1.60 and 1.61 respectively. For plants where dynamic data are available, e.g., ground response spectra for a ~ fuel pool supported by the ground, floor response spectra for fuel pools supported on soil where soil-structure interaction was considered in the pool design or a floor response spectra for a fuel pool supported by the reactor building, the design and analysis of the new i

rack system may be performed by using either the existing input par meters including the old damping values or new parameters in accc,rdance with i

R. G.1.60 and 1.61.

The use of existing input with new damping values l

in R. G. 1.61 is not acceptabic.

Seismic excitation along three orthogonal directions should be imposed si-multaneously for the design of the new rack system. The peak response from each direction should be combined by square root of 'the sum of the squares in accordance with R. G.1.92.

If response spectra are available for a ver-tical and borizontal directions only, the same horizontal response spectra may be applied along the other horizontal directions.

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Submergence in water should be taken into account. The effects of submer-gence are considered on case-by-case basis.

Due to gaps between fuel assemblies and the walls of the guide tubes, addi-

,4 tional loads will be generated by the impact of fuel assemblies during a postulated seismic excitation.

Additional loads due to this impact effect m.

Page 4 of Attachment 3 may b'e-determined by estimating tue kinetic energy of the fuel assembly.

The maximum velocity of the fuel assembly may be estimated to be the spectral velocity associated with the natural frequency of the submerged fuel assembly. Loads thus generated should be considered for local as well as overall effects on the walls of the rack and the supporting framework.

It should be demonstrated that the consequent loads on the fuil assembly do not lead to a damage of the fuel.

Loads generated from other postulated impact events may be acceptable, if the following paramet ers are described:

the total 'riass of the impacting missile, the maximum velocity at the time of impact, and the ductility ratio of the target material utilized to absorb the kinctic energy.

l (4) Loads and Load Combinations l

Any change in the temperature distribution due to the proposed modification should be identified.

Information pertaining to the applicable desigr. loads and various combinations thereof should be provided indicating the thermal load due to the effect of the maximum temperature distribution through the l

pool walls and bcse slab. Temperature gradient across the rack structure i

- I due to differential heating effect between a full and an empty cell should l

be indicated and incorporated in the design of the rack structure. Maximum l

uplift forces available from the crane should be irydicated including the con-sideration of these forces in the design of the racks and the analysis of the existing pool floor, if applicable.

The fuel pool racks, the fuel pool structure, including the pool slab and fuel pool _ liner, should be evaluated for the accident load combinations which include the impact of the spent fuel cask, the heaviest, postulated load drop, and/or

"E;6 5 cf A:tiectr,t 3 acridentel drop of fuel assembly from maximum height as described in paragraph (1) a-The acceptable limits (strain or stress limits) in this case will be reviewed on a case by case basis out, in general, the applicant is required to demonstrate that the functional capability and/

or the structural integrity of each component is maintained.

The specific loads ano load combinations are acceptable if they are in conformance with the applicable portions of Section 3.8.4-II.3 of this plan and Table 1.

(5) Design and Analysis Procedures Details of the mathematical model including a description of how the important parameters are obtained should be provided including the following:

the methods used to incorporate any gaps between the sup-port systems and gaps between the fuel bundles and the guide tubes; the methods used to lump the masses of the fuel bundles and the guide tubes; the methods used to account for the effect of sloshing water on the pool walls; and, the effect of submergence os the mass, the mass distribution and the effective damping of the fuel bundle and the fuel racks.

The design and analysis procedures in accordance with iaction 3.8.4-11.4 of this plan are acceptable.

The effect on gaps, sloshing water, and increase of effective mass and damping due to submergence in water should be quantified.

When pool walls are utilized to provide lateral restraint at higher j

elevations, a determination of the flexibility of the pool walls and

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Page 6 of Attachment 3

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the c'apability of the walls to sustain such loads should be provided.

If the pool walls are flexible (having a fundamental frequency less than 33 hertz), the floor response spectra corresponding to the lateral restraint point at the higher elevation are likely to be greater than those at the base of the pool.

In such a case using the response spectrum approach, two separate analyses should be performed as indicated below:

(a) A spectrum analysis of the rack system using resp,onse spectra cor-responding to the highest support elevation provided that there is not significant peak frequency shift between the response spectra at the lower and higher elevations; and, (b)

A' static analysis of the rack system by subjecting it to the maximum relative. support displacement.

The resulting stresses from the two analyses above should be combined by the absolute sum method.

In order to deternine the flexibility of the pool wall it is acceptable for the applicant to use equivalent mass and stiffness properties obtained from calculations similar to those described in Reference 4.1.

Should the fundamental frequency of the pool wall model be higher than or equal to 33 hertz, it may be assumed that the response of the pool wall and the corre-sponding lateral support to the new rack system are identical to those of the base slab, for which appropriate floor response spectra or ground response spectra may already exist.

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'. :: ' :i ' :: ; ;r.: 3 (6). Structural Acceptance Criteria When ' subsection NF, Reference 3.1 is u',ed for the racks, the structural acceptance criteria are those given in the Table 1.

When buckling loads are considered in the design, the structural acceptance criteria shall be

-limited by the requirements of Appendix XVII to Reference 3.1.

For impact loading the ductility ratios utilized to absorb kinetic energy in the tensile, flexural, compressive, and shearing modes should be quan-tified.

When considering the effects of seismic loads, factors of safety against gross sliding and overturning of racks and rack modules under all probable service conditions shall be in accordance with the Section 3.8.5.

11-5 of this plan. This position on factors of safety against sliding and tilting need not be met provided any one of the following conditions is met:

(a) it can be shown by detailed nonlinear dynamic analyses that the am-plitudes of sliding motion are minimal, and impact between adjacent rack modules or between a rack module and the pool walls is prevented provided that the factors of safety against tilting are within the 1

values permitted by Section 3.8.5.11.5 of this plan.

(b) it can be shown that any sliding and tilting motion will be contained within suitable geometric constraints such as thermal clearances, and

~

that any impact due to the clearances is incorporated. The fuel pool structure should be designed for the increased loads due to the new I

L A

,5 E t i : t :; ~ ' rr I and/or expanded high density racks.

The fuel pool liner leak tight

. integrity should be maintained or the functional capability of the fuel pool should be demonstrated.

1 (7) Materials,- Quality Control, and Special Construction Techniques:

The materials, quality control procedures, and any special construction techniques should be described. The sequence of in,stallation of the new fuel racks, and a description of the precautions to be taken to prevent damage to the stored fuel during the construction phase should be provided.

If connections between the racks and the pool liner are made by welding, the-welder as well as the welding procedure for the welding assembly shall be qualified in accordance with the applicable code.

I TABLE 1 LOAD COMBINATION ACCEPTANCE LIMIT D+L level A service limits D + L + To

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D + L + To + E D + L + Ta + E ---------------------------------------------- level B service. limits D + L + To + Pf D + L + Ta + E' --------------------------------------------- level D service limits D + L + Fd -------------------------------------------------- The functional capability of the fuel racks should be demonstrated Limit Analysis limits of Appendix XVII-4000 to ASME 1.7 (D + L)

Code Section III, 1.3 (D + L) + To)

Division 1.

1.7 (D + L + E) 1.3 (D + L + E + To) t

- 1. 3 ' ' D 4 L + E + Ta) 4 1.1 (u + L + To + Pf) 1.1 (D + L + Ta + E')

- Faga'9 of Attechment 3

- Notes:

1. ~The abbreviations in the table above are those used in Subsection II.3.a of where each term is defined except for Ta which is defined here as the highest temperature associated with the postulated abnormal design conditions.

2.

Deformatit - limits specified by the design specification limits shall be satisfied, and such deformation limits should preclude damage to the assemblies.

- 3.

The provision of,NF 3231.1 of Reference 3.1 shall be amended by the requirements of the paragraphs c. 2, 3 and 4 of the l

R. G.- 1.124 entitled " Design Limits and Load Combinations for l

Class 1 Linear-Type Component Supports."

4.

Fd is the force caused by the accidental drop of the heaviest load from the maximum possible height and Pf is upward force on the racks caused by postulated structural fuel assembly.

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iag: 10 of Attachment 3

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REFERENCES

~1.

Regulatory Guides 1.29 Seismic Design Classification 1.60 Design Response Spectra for Seismic Design of Nuclear

'ower. Plants 1.61

- Damping Values for Seismic Design of Nuclear Power Plants 1.76 Design Basis Tornado for Nuclear Power Plants

'l.92 Com'bining Modal Responses and Spatial Compo'nents in Seismic Response Analysis 1.124 - Design Limits and Loading Combinations for Class 1 Linear-Type Components Supports 2.

Standard Review. Plan

,r.

3.7

- Seismic Design 3.8.4 - Other Category I Structures 3.

Industry Codes and Standards 1.

American Society of Mechanical Engineers, Boiler and Pressure Vessel Code,Section III, Division 1 2.

American National Standards Institute, N210-76 3.

American Society of Civil Engineers, Suggested Specification for Structures of Aluminium Alloys 6061-T6 and 6067-T6 4.

The Aluminium Association, Specification for Alumnium Structures Other 1.

Biggs,' John M., " Introduction to Structural Dynamics,"

McGraw-Hill Book Co., New York, 1964

.n.

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-ATTACHMENT 4 A*

• EN;IX 3 TO 5:.2 SE;TI;V 3.E.4 STP.U;T'JP.tL DESIGN AUDITS 1.

Introduction Appendix 8. " Quality Assurance Criteria for Nuclear Pc*er Plants and Fuel Reprocessing Plants", to 10;RF50, " Licensing of Freduction and Utilization Facilities" requires, in part, that the design control reasures shall provide for verifying or checking the adecuacy or singlified calculational methods, or by the performance of a suitable testing program. This appendix provi[e's' re uirements and guidelines for implementatie : of structural design audits.

2.

Ct.4ectives The audit is conducted in order that the following objectives are accomplished:

4 (a) To investigate f a detail of the manner in which the applica'nt has ' implemented the structural design criteria that' he c;mmitted to use for the. facility.

(b) To verify th&t the key structural design calculations have been condutted in an acceptable way.

(c) To identify and assess the safety significance of these areas where the plant structures were designed and analy:ed using l

methods other than those recommended by the NRC Standard Review J

Plan.

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Page 2 of Attachment 4.

3.

Freliminary Arran;ements

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Arrangements for'the audit are to be made by the Licensing Project Manager (LPM)._ The audit agenda, including specific areas of interest are prepared by the reviewer and forwarded to the applicant at least thirty (30) days prior to the date of the audit., The LPM should notify the appropriate aE regicnal office personnel es well as any intervening parties, if applicable, about the forthcoring audit.

4.

Conduct of the Audit

+

(a) An Ov.erview of the Plant Design:,

The applicant should present an overview of each of the key I

structures including a brief description, assumptions, modeling techniques, and technique features of desig's as,well as any.

deviations from those committed to in the SAR's.

(b) Audit cf Design Calculations:

The auditing-personnel review the design calculations for the structures which have been identified daring the review of the applicant's Design Report. Any ques'.fons such as those regarding l

the structural modeling, analysis, proportioning of the embers,,

and computer ejns should be discussed among the particip' ants in the audit ate : esolved. If such a resolution requires additional engineering data and further analysis on the part of the applicant the specific follcw-up action items should be identified and noted

/

in the meeting minutes for subsequent resolution.

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Page 3 of Attachment 4

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5.

Exit Meeting An exi.t reeting is held at the conclusion of the audit to discuss and sure.arize the audit findings, generic issues pertaining to the design, specific action items, and the schedules for resolution of the action items.

n 6.

Minutes of the Audit The LPM is responsible for preparation o,f the audit minutes'.'

7.

After audit Meetings Review of the applicant's response to the action items may necessitate additicnal w.eting(s) between the staff and the applicant to expl iin sl certain parts of the responses.

8.

Incut to the SER q,

S :

The audit should be censidered as an integral part of the review process.

1 Res:1ution of the action items, together with appr:;riate c:nsideration of othtr safety aspects should constitute the major basis for the staff's I

preparation of the SER.

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