ML13333C008
| ML13333C008 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 02/06/1984 |
| From: | Mckenna E Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| LSO5-84-02-015, LSO5-84-2-15, NUDOCS 8402080292 | |
| Download: ML13333C008 (21) | |
Text
- pJt REG&,4 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 February 6, 1984 Docket No. 50-206 LS05-84-02-015 LICENSEE:
SOUTHERN CALIFORNIA EDISON COMPANY FACILITY:
San Onofre Nuclear Generating Station, Unit No. 1
SUBJECT:
SUMMARY
OF JANUARY 31, 1984 MEETING On January 31, 1984, representatives of Southern California Edison Company (SCE), their consultants, and members of the NRC staff met in Bethesda, Maryland. The purpose of the meeting was to discuss proposed reevaluation criteria for seismic reanalysis. These criteria were developed to support plant restart and operation for the short-term until seismic design issues can be fully resolved. Enclosure 1 is a list of attendees at the meeting. is a set of handouts used during the meeting.
Three main aspects of pipe support and structural member analyses were discussed: (1) inelastic criteria for structural steel members (ductility ratio); (2) the energy balance method application in the pipe support evaluation; and (3) criteria for definition of failure of supports based on yield stress and in some cases 1.3 x yield stress.
The licensee presented their approach for structural members with a ductility ratio based on the plastic moment capacity. The staff raised several concerns about use of the plastic moment capacity but noted that use of a ductility ratio based on the yield displacement would resolve most of these concerns.
The licensee will consiler whether to use the yield displacement approach or to further justify use c alternative criteria. In addition, the licensee agreed to provide the bi 's for the adequacy of the proposed allowable ductility factors.
Clarification was provided at the meeting on the licensee proposed use of the energy balance method. During review of the licensee's restart plan, the staff had concluded that the energy balance method was not appropriate for evaluation of pipe support adequacy. The licensee noted that this method is only being used to reevaluate the functional capability of piping after the postulated failure of some supports in the piping supports evaluation. The staff agreed that this approach seems reasonable for estimating the effects on the piping of support failure and stated that an audit of the analysis results will be performed.
6402080292 840206 PDR ADOCK 05000206 P
S2 February 6, 1984 With regard to the criteria for support failure, the staff recommendation is the ASME Code yield stress. However, on a case-by-case basis, the staff will consider a support functionally capable if the peak stress does not exceed about 30% more than the yield stress because of inherent ductility strength of the support system. Such cases must be identified so that the specific application can be reviewed by the staff to ensure that there are no special conditions present which would alter the staff's judgement of adequacy.
Original signed by Eileen M. McKenna, Project Manager Operating Reactors Branch #5 Division of Licensing
Enclosures:
- 1. List of Attendees
- 2. Meeting Handouts cc w/enclosures:
See next page DISTRIBUTION Docket File NRC PDR Local PDR NSIC ORB #5 Reading DCrutchfield HSmith EMcKenna WPaulson OELD ELJordan JMTaylor ACRS (10)
FMiraglia NRC Participants D: 0R D
EMcKenna:cc DClfhfield L/(0/84
/2-/&/84
3 -
February 6, 1984 cc Charles R. Kocher, Assistant Mr. Kenneth P. Baskin General Counsel Vice President, Nuclear Engineering James Beoletto, Esquire Licensing and Safety Department Southern California Edison Company Southern California Edison Company Post Office Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Post Office Box 800 Rosemead, California 91770 David R. Pigott Orrick, Herrington & Sutcliffe 600 Montogmery Street San Francisco, California 94111 Harry B. Stoehr San Diego Gas & Electric Company P. 0. Box 1831 San Diego, California 92112 Resident Inspector/San Onofre NPS c/o U.S. NRC P. 0. Box 4329 San Clemente, California 92672 Mayor City of San Clemente San Clemente, California 92672 Chairman Board of Supervisors County of San Diego San Diego, California 92101 California Department of Health ATTN: Joseph 0. Ward, Chief Radiation Control Unit Radiological Health Section 714 P Street, Room 498 Sacramento, California 95814 U.S. Environmental Protection Agency Region IX Office ATTN: Regional Radiation Representative 215 Freemont Street San Francisco, California 94111 John B. Martin, Regional Administrator Nuclear Regulatory Commission, Region V 1450 Maria Lane Walnut Creek, California 94596
LIST OF ATTENDEES Meeting of January 31, 1984 San Onofre Unit No. 1 NAME AFFILIATION Eileen McKenna NRC Selcuk Atalik Bechtel Mike Knarr SCE Jerry Gartland SCE Randy Wheaton IMPELL Russell W. Krieger SCE Jack Rainsberry SCE Thomas Cheng NRC Paul Koss Bechtel Chris Grimes NRC SAN ONOFRE NUCLEAR GENERATING STATION UNIT 1 SCE/NRC MEETING JANUARY 31, 1984
PROCEEDURE FOR REVIEW OF STRUCTURES FOR PIPE LOADS (1) GROUP STRUCTURAL MEMBERS IN EACH AREA BY SIMILAR SIZES, SPANS & LOADS (2) USING PRELIMINARY CALCULATIONS AND ENGINEERING JUDGEMENT SELECT THE GOVERNING CASE FOR EACH GROUP (3) EVALUATE STRESSES FOR THE GOVERNING CASE o
BEAM ELASTIC OK 0
BEAM DUCTILITY== 3.0 OK 0
BEAM DUCTILITY -==10.0 CASE 'Y CASE REVIEW (4) IF BEAM EXCEEDS ALL CRITERIA IN (3) o DESIGN MODIFICATION o
SELECT NEXT GOVERNING MEMBER AND REPEAT STEP (3)
(5) ONCE GOVERNING CASE IS SHOWN ACCEPTABLE REMAINING MEMBERS ARE CONSIDERED ACCEPTABLE
COMPUTATION OF DEMAND DUCTILITY o
"DEVELOPMENT OF CRITERIA FOR SEISMIC REVIEW OF SELECTED NUCLEAR POWER PLANTS" NEWMARK, N..M.,
AND HALL, W., J., NUREG/CR-0098. MAY 1978 o
"BALANCE OF PLANT STRUCTURES SEISMIC REEVALUATION CRITERIA" SAN ONOFRE NUCLEAR GENERATING STATION, UNIT 1. FEBRUARY, 1981 o
"SYSTEMATIC EVALUATION PROGRAM POSITION RE: CONSIDERATION OF INELASTIC RESPONSE USING THE NUREG/CR-0098 DUCTILITY FACTOR APPROACH" LETTER W. PAULSON TO R. DIETCH DATED JUNE 23. 1982.
Fc AREA I dr dc do DEMAND DUCTILITY
FROM EQUALITY OF AREAS (ENERGY)
(d -d )*R=1/2 (F -R)*(d -d) c c
c r
d = INELASTIC DEFORMATION DUE TO F Fce FORCE COMPUTED ELASTICALLY Sda /dr= DUCTILITY /4 SINCE F /dj= R/dr S
=~ 1/2
[(Fc / R)+ I
THEN Fc / R=
2-^ - 1)
ALSO d c/dr= (2 d a/ d =
/
(2 1A - 1)
PLASTIC ANALYSIS AND DESIGN, MASSONNET. C.E. AND SAVE. M.A.
BLAISDELL PUBLISHING COMPANY, 1965 o
OBTAINED THEORETICAL MOMENT-CURVATURE RELATIONSHIPS BASED ON TESTS o
RECOMMEND THAT THE CURVE BE REPLACED BY TWO STRAIGHT LINES:
THE BEAM REMAINS ELASTIC UNTIL THE ULTIMATE PLASTIC MOMENT IS REACHED AND THEN BENDS PLASTICALLY UNDER A CONSTANT MOMENT o
FOR A TYPICAL 18WF45 COMPARISON OF AREAS SHOW THAT THIS RESULTS IN AN ERROR OF ABOUT 2 PERCENT
FLANGE YIELDING
-LINEAR WEB YIELDING 1.135-I.0 -
M/Me K/Ke MOMENT CURVATURE RELATION FOR 18W45
IN ADDITION THEY STATE:
0 "THE ULTIMATE PLASTIC STRENGTH OF A BEAM SUBJECTED TO BENDING. AXIAL FORCE, AND SHEAR DEPENDS ONLY ON THE BENDING MOMENT........"
0 "FOR BENDING ABOUT THE STRONG AXIS......... THE INFLUENCE OF THE AXIAL FORCE N MAY BE NEGLECTED AND M=MP MAY BE USED WHEN N
0.15NP" 0
"FOR BENDING ABOUT THE WEAK AXIS, M APPROXIMATELY EQUALS MP AS LONG AS N< O.4NP....."
INTERACTION FORMULAS p
- .85M-)
The first two terms represent the single axis bending as defined by equation 2.4-3 of the AISC specification. The interaction equation relation for axial load and minor axis bending only is:
Py +TIm Me P +
1 M
(2) per Reference 9.
The Structural Stability Research Council's Guide to Stability Design Criteria for Metal Structures, 3rd Ed. (Reference 2) and the latest Canadian Standards Association code, Steel Structures for Buildings -
Limit States Design (Reference 10), state that for strength considerations the ultimate design capacity of a column subjected to blaxial bending can be represented by equation (1).
Therefore, this equation is used in evaluating the ultimate strength of beam-columns. For long, slender columns, if the stability considerations govern they will be taken into account.
5
72 66 60 54
- 42.
NOTES:
I. YIELD POINT RANGES FROM 38 TO 53 ksi
- 2. ULTIMATE STRESS FROM 61 TO 78 ksl
- 3. STRAIN AT ULTIMATE RANGES FROM 15% TO 28%
4 ELONGATION RANGES FROM 220% TO 46%
a2 in is 12 6
0 0
2 4
6 8
10 12 14 16 18 20 22 24 26 28 30 32 34 STRAIN %
EXPERIMENTAL S TR ESS - STRA IN BEHAVIOR OF A-36 STEEL
2:Fy=36 Fy=36 Fy=36 (Fy+Fsh)
(+Fsh) 6000 42.2 60.0 500 j--v Fy = 316 N. A..
500 0
0
.0 Stress vs Strain Mp=Z.FyK32?9_k-in 3000(Q D
2000
-4
-4 x
x ii II Strain %
12 3
4I 6
7 8
9 10 11 12 13 14$
15 MOMENT CAPACITY OF 18WF45
6000 5000 tAuCapac;ty 4000 Mp=Z.Fy3229 k-in 3000 2000 1000 Strain %
III III 1
2 3
4 5
6 7
8 9
10 11 12 13 14 15 MOMENT CAPACITY VS DUCTILITY DEMAND