ML19340D963
| ML19340D963 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 12/09/1980 |
| From: | Furr B CAROLINA POWER & LIGHT CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-80-11, NO-80-1739, NUDOCS 8101050638 | |
| Download: ML19340D963 (3) | |
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December 9,1980 y
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s FILE:
NG-3513 (B)
SERIAL:
NO-80-]739
.Mr. James P. O'Reilly S. Nuclear Regulatory Commission Region II 101 Marietts Street, Suite ^100 Atlanta, GA 30303 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS. 1 AND 2 LICENSE NOS. DPR-71 AND DPR-62 DOCKET NOS.(F32T ANIL5fl=J3P SUPPLEMENTAL RESPONSE TO IE BULLETIN 80-11
Dear Mr. O'Reilly:
Enclosed you will find Carolina Power & Light Company's (CP&L) supplemental response to IE Bulletin 80-11.
This response addresses additional information required by Item 2b (iii) (a), concerning the Brunswick Plant Diesel Generator Building.
This supplemental response completes CP&L's response to IE Bulletin 80-11.
Should you have questions regarding our response, please contact my staff.
Yours very truly,
.A W q.
Furr Vic President Nuclear Operations DCS:tma*
Enclosure cc:
Mr. N. C. Moseley Sworn to and subscribed before me this day of 1980.
Notary Public My commission expires A & &38 1
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Report for Diesel Generator Building The on-site survey revealed the following:
1.
Walls 4a, Sa, 5b, Sc, and 6d have the designed restraint angles missing from the top of the walls.
2.
Wall 4a has some loose concrete brick at the top of the wall just under the upper slab.
3.
Walls 2a, 2b, 2c, and 2d have horizontal channels to provide support against lateral loads.
Channels are located below duct openings on top of the walls, however the connection angles to the supporting concrete columns are missing.
4.
No safety-related piping is attached to any masonry walls.
Light items such as an electrical. panel, a junction box, etc.,
are attached.
The walls listed in Items 1, 2, and 3 will be corrected.
All safety-related masonry walls were reevaluated using floor response spectra curves specially developed for this report. The reevaluation calculations followed the Acceptance Criteria of Appendix 80-11-A from our November 5, 1980 submittal and embraced OBE and DBE seismic input.
Conclusions about the walls follow:
1.
Wall 4a has restraint angles missing and loose concrete brick at the top of the wall. The extent of the loose brick is not known.
The wall is reinforced vertically.
Under DBE seismic forces, Wall 4a is acceptable.
Collapse of this wall would not affect the Diesel Generators. Wall 4a will be repaired with first priority.
f To reduce the stresses in Wall 4a to allowable range under OBE and DBE seismic forces, it is necessary to add vertica? pilasters l
at about 20-foot intervals.
l Wall 4a will be modified with steel pilasters.
I 2.
Walls 9c and 9d are firewalls around stairwells.
Stairwells l
are covered with a concrete slab about 8 feet above the floor.
l Walls 9c and 9d span vertically and depend on the cover slab to support the upper ends of the walls.
The cover slabs require
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modification near Walls 9c and 9d so they can support the loads and transfer them to the end wall thence to the floor slab.
i The.csults of the calculations were recorded as a stress factor; is a:. ratio of actual stress to allowable stress.
The range of stress factors is given below:
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Reinforced Wall OBE DBE Masonary - Compression 0.03 to 0.75 0.03 to 0.65 Mortar - Shear 0.06 to 0.81 0.03 to 0.090 Reinforcing - Tension 0.05 to 1.00 0.04 to 1.00 Reinforcing - Bond 0.11 to 0.90 0.10 to 1.00 Nonreinforced Masonry - Compression 0.02 to 0.03 0.01 Masonry - Tension 0.30 0.21 to 0.25 Mortar - Shear 0.02 to 0.04 0.03 to 0.04 Conclusions All safety-related concrete masonry walls in the Diesel Generator Building will maintain structural integrity during a seismic event.
l Three walls will be upgraded to meet code criteria.
MLB/tma (476/523) n j