ML20137Y525

Interim Deficiency Rept (CDR 85-00-12) Re Error in Section of Gt Strudl Program That Calculates Frequencies Using Rayleigh Quotient Method.Initially Reported on 850812.Next Rept Will Be Submitted by 851115

ML20137Y525
Person / Time
Site:	Seabrook
Issue date:	09/16/1985
From:	Devincentis J PUBLIC SERVICE CO. OF NEW HAMPSHIRE
To:	Starostecki J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
(CDR-85--12), (CDR-85-00-12), SBN-870, NUDOCS 8510080022
Download: ML20137Y525 (3)

Text

, SEABROOK STATION Engineering Office e)(" \ ! .

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- s.,*. - e New Hampshire Yankee Division September 16, 1985 SBN-870 T.F. Q2.2.2 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 Attention: Mr. Richard W. Starostecki, Director Division of Project and Resident Programs Refernces: (s) Construction Permits CPPR-135 and CPPR-136, Docket Nos. 50-443 and 50-444 (b) Telecon of August 12, 1985, D.E. Groves (YAEC) to J. Grant (NRC Region I)

Subject:

Interim 10CFR50.55(e) Report; GT STRUDL Computer Program Error (CDR 85-00-12)

Dear Sir:

On August 12, 1985, we reported a potential 10CFR50.55(e) item to Region I 1 Reference (b)]. The following information is provided under the interim reporting provision of 10CFR50.55(e)(3):

Description of Deficiency The GT STRUDL Computer Program, which is marketed by Control Data Corporation and supported by Georgia Institute of Technology, was used in the design and analysis of duct supports and pipe supports for SeabrookpriortoJanuarY1984.

In performing an analysis check on a previously completed duct support designed with the GT STRUDI. Program, an error was discovered in the section of the program that calculates frequencies using the Rayleigh Quotient Method.

Georgia Tech confirmed the error in all versions of the program prior to the 84.03 Release. The error had unknowingly been corrected in all sub-sequent releases including the 84.03 version.

8510080022 850916 PDR S ADOCK 05000443 pg Seabrook Station Construction Field O'fice P O. Box 700 . Seabrook, NH 03874 ) D i y M

United States Nuclear Regulatory Commission

, Attention: Mr. Richard W. Starostecki Page 2 Control Data Corporation has further clarified the nature of errors in the GT STRUDL Program. These errors are summarized below:

1. An error in the Rayleigh frequency calculation for versions of GT STRUDL prior to Version 84.03. -

2. Incorrect or confusing documentation for Rayleigh frequency load-ing in all versions including current Verison 85.03.

Both of these errors result in GT STRUDL calculating frequencies higher than actual.

Scope of Computer Runs Affected We have determined that 960 computer runs are af fected by these errors, the majority (800) being in HVAC support area. Other areas affected are:

pipe supports, I&C supports and pipe whip restraints.

Analysis of Safety Implications A sample of 25 computer runs have been taken for evaluation. The 4

selection was on the basis that the new frequency of the selected supports will be substantially lower than calculated earlier. New analyses were performed using the correct GT STRUDL version with proper input.

A thorough evaluation of all 25 runs has not been completed, but preliminary results indicate that support designs are not impacted by these errors.

We will continue our analysis of this deficiency and provide a follow-I up report by November 15, 1985.

Very truly your ,

tus .

John DeVincentis, Director Engineering and Licensing a

cc: Atomic Safety and Licensing Board Service List

a William S. Jordsn,111 Donald E. Chick Diane Curran Town Manager Harmon, Weiss & Jordan Town of Exeter 20001 S. Street, N.W. 10 Front Street Suite 430 Exeter, NH 03S33 Washington, D.C. 20009 Brentwood Board of Selectmen Robert G. Perlis RED Dalton Road Office of the Executive Legal Director Brentwood, NH 03833 U.S. Nuclear Regulatory Com:sission ,

Washington, DC 20555 Richard E. Sullivan, Mayor l City Hall Robert A. Backus, Esquire Newburyport, EA 01950 1161,owell Street P.O. Box 516 Calvin A. Cancey Manchester, NH 03105 City Manager City Hall Philip Ahrens, Esquire 126 Daniel Street Assistant Attorney General Portsmouth, NH 03801 l Dana Bisbee, Esquire Mr.' John B. Tanzer Assistant Attorney General Designated Representative of Office of the Attorn'ey General the Town of Hampton 208 State House Annex 5 Morningside Drive Concord, NH 03301 i Hampton, NH 03842 i Anne Verge, Chairperson Roberta C. Pevear Board of Selectmen Designated Repyesentativt of Town Hall the Town of Hampton Falls South Hampton, NH 03827 Drinkwater Road Hampton Falls, NH 03844 Patrick J. McLeon 5 Selectmen's Office Mrs. Sandra Gavutis 10 Central Road Desig.nated Representa'tive of Rye, NH 03870 the Town of Rensington RFD 1 Carole F. Kagan, Esquire

East Kingston, NH 03827 Atomic Safety and Licensing Board Panel l U.S. Nuclear Regulatory Commission Jo Ann Shotwell . Esquire 42ashington, DC 20555 Assistant Attorney General Environmental Protection Bureau Mr. Angi Machiros Department of the Attorney General Chairman of the Board of Selectmen One Ashburton Place, 19th Floor Town of Newbury Boston, MA 02108 Newbury, MA 01950 Nnster Gordon J. Bumphrey Town Manager's Of fice U.S. Senate .

Town Ec11 - Friend Street -

Washington,3C 20510 A===hury, MA 01913 (iTIN: Tom Screek) Senator Gordon J. Humphrey 1 Pillsbury Street.

l Diana P. Randall Concord, NH 03301 70 Collins Street (ATTN: Herb Boynton)

Seabrook, NH 03874 'l 1

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