ML20141E744
| ML20141E744 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/20/1985 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20141E736 | List: |
| References | |
| IEB-80-11, TAC-60116, NUDOCS 8601080299 | |
| Download: ML20141E744 (1) | |
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SUPPLEMENTAL SAFETY EVALUATION MASONRY WALL DESIGN. IE BULLETIN 80-11 NORTHEAST NUCLEAR ENERGY COMPANY, ET AL.
MILLSTONE NUCLEAR POWER STATION UNIT 2 DOCKET NO. 50-336 In the Safety Evaluation (SE), the staff concluded that except for three walls qualified by the licensee via the use of the energy balarce technique to resist the out-of-plane forces, items 2(b) and 3 of IE Bulletin 80-11 have been fully implemented at the Milistone 2 facility for the remaining safety related walls. The SE also included a staff position in the energy-balance technique and stated that the implementation of this position was required to render the walls acceptable to the staff.
By a letter dated October 28, 1985, the licensee informed the staff of the results of the reanalysis of the three walls. The reanalysis is based on the linear elastic working stress methodology consistent with the staff acceptance erfteria delineated in SRP Section 3.8.4, Appendix A.
In the reanalysis, t he finite element model is used to define the wall geometry to account for the plate action (the original analysis used one-way span assumption).
The results of the reanalysis indicate that the three walls can now be qualified on the basis of the working stress criteria and the calculated stresses in the walls are within the staff allowables.
Based on the above findings, the staff concludes that the issues regarding energy-balance technique at Millstone 2 have been resolved, and there is a reasonable assurance that all safety related rrasonry walls at Millstone 2 will withstand the specified design load conditions without impairment of wall integrity or the performance of the required safety functions.
-Principal Contributor:
N. Chokshi 8601080299 851220 PDR ADOCK 050 36 L