ML20117N161

Advises That Discussion Re Qualification of 75 Masonry Walls Per IE Bulletin 80-11 Will Be Submitted by 850923,per NRC 850312 Request.Linear Elastic Working Stress Analysis & Results for Four Walls Will Be Discussed

ML20117N161
Person / Time
Site:	Davis Besse
Issue date:	05/10/1985
From:	Crouse R TOLEDO EDISON CO.
To:	Stolz J Office of Nuclear Reactor Regulation
References
1153, IEB-80-11, NUDOCS 8505170411
Download: ML20117N161 (2)

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-Docket No. 50-346 7gL,gg

. License No. NPF EDISON Serial No. 1153 - RCHARD P. CROUSE Vce Prendert May 10, 1985- Esaai .

Director of Nuclear Reactor Regulation Attention: Mr.' John F. Stolz Operating Reactor Branch No. 4

' Division of Licensing United States Nuclear Regulatory Commission Washington, D.C.. 20555

Dear Mr. Stolz:

On March 12, 1985, the NRC issued an Information Request pursuant to 10 CFR 50.54(f) (Log No. 1716). This letter requested Toledo Edison (TED) to identify the actions and schedule planned to implement the NRC Structural and Geological Engineering Branch (SCEB) Staff position for 75 masonry walls qualified under IE Bulletin 80-11 (Log No. 1-362),

utilizing the energy balance technique at the Davis-Besse Nuclear Power Station Unit No. 1.

In our April 19, 1985 response to your letter (Serial No. 1149) we stated that TED representatives were scheduled to meet with the NRC Staff to present a viable method for qualifying the 75 masonry walls in question without using the energy balance technique. On April 25, 1985, TED representatives met with the NRC Staff and presented a generalized method of reducing the conservatisms from our analysis and qualifying these i masonry walls by linear elastic working stress analysis. This approach was received favorably by the NRC Staff. The NRC Staff requested that TED provide a formal submittal of its method of qualifying these walls by linear elastic working stress analysis, and address the four specific items listed in Enclosure 1.

Accordingly, by September 23, 1985, TED will submit to the NRC: 1) a formal discussion of our method of qualifying the 75 walls by linear

-elastic working stress analysis; 2) address the Staff's requests of Enclosure 1;'and 3) provide the results of detailed analyses for the four most highly stressed masonry walls (numbers 5197, 2371, 5157 and 1038) to be qualified. Wall 5367 will be modified to achieve qualification and will not'be included. Scheduling for the modification of Wall 5367 will be handled under our Integrated Living Schedule Program process.

Very truly yours, 8505170411 PDR 850510 G ADOCM 05000346 h 8P h / , PDR t/

RPC:DRW:CLM:lah I cc: DB-1 NRC Resident Inspector THE TOLEOO EDISON COMPANY - EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43652

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Docket No.-50-346-

.Lic n o No,1NPF-3

Serial No.;1153

Enclosure:

1 Additional Information to be-Provided on Masonry Walls (1) Provide clarification regarding the method of analyses used to f qualify Wall No. 2297. t (2) Provide a discussion on the effects of cutouts on the reduction factors ~resulting from consideration of plate action.

'(3) Provide a discussion on the applicability of a reduction factor and conclusions"to OBE load conditions.

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-(4)' The NRC Staff position requires that'the'. maximum stress in the

-Durowal1~ type of-horizontal reinforcements be limited to 30,000 psi.

In view of this, provide a discussion on your approach to comply with~

the Staff requirements. Provide details on the. anchoring of the Lhorizontal reinforcements and why it is adequate for the moment transfer.

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