ML16341D675
| ML16341D675 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 03/27/1986 |
| From: | Schierling H Office of Nuclear Reactor Regulation |
| To: | Shiffer J PACIFIC GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8604040544 | |
| Download: ML16341D675 (30) | |
Text
Docket Nos.
50-275 and 50-323 March 27, 1986 Mr. J.
D. Shiffer, Vice President Nuclear Power Generation c/o Nuclear Power Generation, Licensing Pacific Gas and Electric Company 77 Beale Street, Room 1451 San Francisco, California 94106
Dear Mr. Shiffer:
SUBJECT:
LONG TERM SEISMIC PROGRAM (LTSP) 0 DI RI BUT ION cet ie L PDR PAD-3 Rdg OELD B. Grimes, ACRS 10 H. Schierling L. Reiter S.
Brocoum D. Jeng R. Ballard NRC PDR Gray File, H. Thompson, E. Jordan J. Partlow C.
Vogan E. Rossi G. Giese-Koch L.
Ong N. Chokshi F.
Cor)gel Enclosed are individual comments by the four members of the NRC advisory panel on soil structure interaction for the Diablo Canyon LTSP.
The comments are based on their review of your LTSP plan and the meeting on October 21, 1985.
A summary of that meeting, dated November 7,
- 1985, had been provided earlier to you.
The staff is reviewing the comments.
We are providing the comments for your consideration in your ongoing soil structure interaction effort.
We do not require at this time that you address these comments.
/s/HSchierling
Enclosures:
As stated cc w/enclosures:
See next page Hans E. Schierling, Senior Project Manager PWR Project Directorate No.
3 Division of PWR Licensing-A
- SEE PREVIOUS PAGE FOR COCURRENCES PAD-3*
PAD-3 BC/PWR-A*
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Docket Nos.
50-275 and 50-323 Mr. J.
D. Shiffer, Vice President Nuclear Power Generation c/o Nuclear Power Generation, Licensing Pacific Gas and Electric Company 77 Beale Street, Room 1451 San Francisco, California 94106
Dear Mr. Shiffer:
SUBJECT:
LONG TERM SEISMIC PROGRAM (LTSP)
DISTRIBUTION L
PDR PAD-3 Rdg OELD B. Grimes ACRS 10 H. Schier ling L. Reiter S.
Brocoum D. Jeng R. Ballard NRC PDR Gray File H. Thompson E. Jordan J. Partlow C.
Vogan E.
Rossi G. Giese-Koch L. Ong N. Chokshi F. Congel Enclosed are individual comments by.the four members of the NRC dvisory panel on soil structure interaction for the Diablo Canyon LT The comments are based on their review of your LTSP plan and meeting on October 21, 1985.
A summary of that meeting, dated Nov er 7, 1985, had been provided earlier to you.
The staff is reviewin the comments.
We are providing the comments for your consideration in ur ongoing soil structure interaction effort.
We do not require at this me that you address these comment.
Enclosures:
As stated ns E. Schierling, Senior Project Manager PWR Project Directorate No.
3 Division of PWR Licensing-A cc w/enclos es:
See next ge PAD-3 ~
PAD-3 CVogan HSchie i g;ps 03/2i/86 03/g/86 BC/
RBalla d
03/'0/86 D
A Va
Mr. J.
D. Shiffer Pacific Gas and Electric Company Diablo Canyon ccrc Philip A. Crane, Jr.,
Esq.
Pacific Gas
& Electric Company Post Office Box 7442 San Francisco, California 94120 Mr. Malcolm H. Furbush Vice President - General Counsel Pacific Gas
& Electric Company Post Office Box 7442 San Francisco, California 94120 Janice E. Kerr, Esq.
'alifornia Public Utilities Commission 350 McAllister Street San Francisco, California 94102 Mr. Frederick Eissler, President Scenic Shoreline Preservation Conference, Inc.
4623 More Mesa Drive Santa
- Barbara, Cali forn'ia 93105 Ms. Elizabeth Apfel,berg 1415 Cozadero San Luis Obispo, California 93401 Mr. Gordon A. Silver Ms. Sandra A. Silver 1760 Alisal Street San Luis Obispo, California 93401 Harry M. Willis, Esq.
Seymour
& Willis 601 California Street, Suite 2100 San Francisco, California 94108 Mr. Richard Hubbard MHB Technical Associates Suite K
1725 Hamilton Avenue San Jose, California 95125 Resident Inspector/Diablo Canyon NPS c/o US Nuclear Regulatory Commission P. 0.
Box 369 Avila Beach, California 93424 Ms.
Rave Fleming 1920 Mattie Road Shell Beach, California 93440 Joel
- Reynolds, Esq.
John R. Phillips, Esq.
Center for Law in the Public Interest 10951 West Pico Boulevard Third Floor Los Angeles, California 90064 Mr. Dick Blankenburg Editor
& Co-Publisher South County Publishing Company P. 0.
Box 460 Arroyo Grande, California 93420 Bruce Norton, Esq.
Norton, Burke, Berry
& French, P.C.
202 E.
Osborn Road P. 0.
Box 10569
- Phoenix, Arizona 85064 Mr.
W.
C. Gangloff Westinghouse Electric Corporation P. 0.
Box 355 Pittsburgh, Pennsylvania 15230 Davi d F.
Fl ei scha ker, Esq.
P. 0.
Box 1178 Oklahoma City, Oklahoma 73101 Mr. John Marrs, Managing Editor San Luis Obis o Count Tele ram Tribune o nson venue P. 0.
Box 112 San Luis Obispo, California 93406
Pacific Gas
& Electric Company Diablo Canyon CC:
Arthur C. Gehr, Esq.
Snell 8 Wilmer 3100 Valley Center Phoenix, Arizona 85073 Mr. Leland M. Gustafson, Manager Federal Relations Pacific Gas II Electric Company 1726 M Street, N.W.
Suite 1100 Washington, DC 20036-4502 Regional Administrator, Region V
U.S. Nuclear Regulatory Commission 1450 Maria Lane Suite 210 Walnut Creek, California 94596 Michael J.
Strumwasser, Esq.
Special Counsel to the Attorney General State of California 3580 Wilshire Boulevard, Suite 800 Los Angeles, California 90010 Mr. Tom Harri s Sacramento Bee 21st and 0 Streets Sacramento, California 95814 Mr. H. Daniel Nix California Energy Commission 1516 9th Street, MS 18 Sacramento, California 95814 Lewis Shollenberger, Esq.
US Nuclear Regulatory Commission Region V
1450 Maria Lane Suite 210 Walnut Creek, California 94596 Mr. Thomas Devine Government Accountability project Institute for Policy Studies 1901 Oue Street, NW Washington, DC 20009 Chairman San Luis Obispo County Board of Supervisors Room 220 County Courthouse Annex San Luis Obispo, California 93401 Director Energy Facilities Siting Division Energy Resources Conservation and Development Commission 1516 9th Street Sacramento, California 95814 President California Public Utilities Commission California State Building 350 McAllester Street San Francisco, California 94102 Mr. Joseph
- 0. Ward, Chief Radiological Health Branch State Department of Health Services 714 P Street, Office Building 88 Sacramento, California 95814
Pacific Gas 5 Ele ic Company Or.
S.
T. Algermissen U.
S. Geological Survey P. 0.
Box 25046 Mail Stop 966 Denver Federal Center Denver Colorado 80225 Or. Keiiti Aki Dept. of Geological Sciences Univeristy of Southern California Los Angeles, California 90089 Dr. Ralph J. Archuleta Dept, of,.Geological Sciences University of California Santa Barbara Santa Barbara, California 93106 Mr. Don Bernreuter Lawrence Livermore Laboratory P. 0.
Box 808 Livermore, California 94550 Mr. Donald A. Brand Vice President, Engineering Pacific Gas E Electric Company 77 Beale Street, Room 2645 San Francisco, California 94106 Dr. Robert D. Brown, Jr.
U.S. Geological Service Building 8, 8977 345 Middlefield Road Menlo Park, California 94025 Mr. Loyd S. Cluff Pacific Gas 5 Electric Company 77 Beale Street, Room 2661 San Francisco, California 94106 Dr.
C. J. Costantino 4 Rockingham Road Spring Valley, New York 10977 D t
o Canyon Dr. George Gazetas JEC 4049 Renssalear Polytechnic Institute
- Troy, New York 12180-3590 Dr. David Perkins U. S. Geological Survey P. 0.
Box 25046 Mail Stop 966 Denver Federal Center
- Denver, Colorado 80225 Dr. Morris Reich Structural Analysis Division Building 129 Brookhaven National Laboratory
Box 808 Livermore, California 94550 Dr. Da.vid B.
Slemmons 2995 Gol den Va1 1 ey Road
- Reno, Nevada 89506 Dr. Andrew S. Veletsos 5211 Paisley Avenue
- Houston, Texas 77096 Dr. Robert V. Whitman Room 1-342 Massachusetts Institute of Technology Cambridge, Massachusetts 02139 Dr. James Davis State Geologist California Division of Mines and Geology Room 1351 1416 Ninth Street Sacramento, California 95814 Dr. Steven M. Day S-Cubed P. 0.
Box 1620 La Jolla, California 92038
ENCLOSURE 1
R 0 9 E R T V. MfH I T M A N MASSACMUSETTS INSTITUTE OF TECHNOI OCT, CAMSIIIOQE MA 02139 October 22, 1985 Dr. Morris Reich Head, Structural Analysis Division Department of Nuclear Energy Building 129 Brookhava National Laboratory
- Upton, Long Island, New York 11973
Dear Morris:
Here are the principal points that stick in my mind after the meeting on 21 October concerning the "Long Term Seismic Program for the Diablo Canyon Power Plant".
My principal c'oncern is the meaning of "free field" ground motions at a site with considerable topographic relief. It seems to me that the effect of the seaside cliff and adjacent mountain may well have as great an effect upon the motions experienced by the plant as the 3-dimensional nature of the foundations for the several buildings.
I would urge that the topographic effects be included in the foundation model por-tion of analyses made with the SASSI computer code.
I think the 5-point work program presented by Mr. Nhite should really be a 6-step effort, with his 4th item split into two parts - so as to permit a careful reflection upon the results obtained by the several types of analyses before the method to be used for production runs is selected.
Returning to my principal concern, it is clear that our group of consultants must stay in close contact with the group that is reviewing the proposal free-field motions.
Clear communication here is vital.
Incidentally, any motions recorded by the 3 "free field" instruments shown in Fig. 7.3-1 of the Plan would all be influenced by topographic features-an observation@'hich emphasizes the problem of defining "free field" at such a site.
RVH:ccc Best regards, Robert V. Nhitman
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ENCLOSURE 2
25 October 1985 REPORT TO:
Morris Reich/ B'rookhaven National Laboratories FRY:
George
- Gazetas, Member Panel of Consultants
SUBJECT:
Long Term Seismic Program (LTSP) for the Diablo Canyon Nuclear Power Plant (DCPP)
Soil Structure Interacti on (SSI) Studies After carefully studying the PG 8
E Program Plan of the
- LTSP, and follow-ing the meeting in Washington (10/21/85) of the Panel of Consultants with representatives of the NRC and the PG 8 E, I would like to make several comments and recommendations regarding the planned SSI studies.
The basic approach described in the Program Plan is to use two state-of-the-art computer
= programs, CLASSI and
- SASSI, for performing a
fairly comprehensive series of parameter studies.
In these studies several models of I
the main power plant structures (of varying degrees of sophistication) and the underlying rock will be subjected to a host of vertical and inclined body
- waves, as well as to surface travelling waves.
The magni tude, frequency characteri sti cs, and parti ci pati on of each of these wave components wi 1 1 be varied parametrically and will be consistent with the "free-field" motion(s) which would result from the GROUND MOTION (numerical) studies.
Of the two computer codes, CLASSI utilizes an analytical formulation and can treat with no difficul ty subsoil profi les consisting of horizontal homogeneous layers, including a
last layer of infinite thickness.
It cannot possibly treat embedment, and in its present fonncan only handle absolutely
2 rigid ground-structure interfaces.
On the other hand, SASSI is based on a
finite-e1ement discretization and can handle easily any degree of embedment, and a finite flexural rigidity of the foundation basemat.
However, it can only approximately (and at a
substanti al cost) treat a
bottom 1 ayer of infinite extent (hal fspace).
- Moreover, for 3-Dimensional non-axi symmetric geometries, as is the case
- here, running SASSI is not an easy task, due to substantia1 computer memory and time requirements, and also due to significant amount of needed manpower.
Therefore, the basic approach of the PROGRAM
- PLAN, i.e. of usi ng CLASSI for the bulk of the parameter
- studies, and then making use of SASSI to "calibrate" the results of CLASSI seems basically sound.
- However, the following items are worth taking into account during this program:
(a)
REGARDING THE INPUT ~MOTION S:
Specifying the "free-field" motion and decomposing. it into various types of waves (to be then used as excitation) may not be as straightforward in this particular case.
The topography of the site seems rather complex, with a high vertical cliff a few hundred feet from the main plant structures, and several hills in the background.
It is not clear whether and how the effects on the motion of these local topographic features will be assessed.
However, in view of the fact that the main plant structures are founded on rock, it mi ght turn out that topographi c wave "scattering" and "focusing" effects are of the same order of magnitude with the effects of SSI.
It may therefore be recommended that such effects be. at least roughly, assessed, e.g.
through a
survey of the pertinent literature.
In principle, of course, it would have been interesting to attempt to realistically model the topography of the site as part of the "Ground Motion (Numerical)" studies (task 6 of the Program Plan).
I am not sure,
- however, whether such modeling is feasible within the current state-of-the-art.
In any '
- case, this is something that should be given consideration during task 6.
(b)
REGARDING THE SSI ANALYSES:
The dynami c SSI analysi s of each containment structure (unit I or 2) would have been a rather straight forward task.
- Things, however, are more complicated due to the presence of a number of closely spaced structures (two units, turbine building, auxiliary building, etc.),
each having its own distinct dynamic characteristics, and
. its own foundation elevation, and foundation si ze and rigidity.
Such an, arrangement poses some difficult modeling problems.
Analysis of a comprehensive model of the whole system (including the superstructures and the ground) is, of course, out of the question.
The real question then is what degree of idealization and simplification would still lead to realistic results and would allow p
ig f<< ~life ph i
ddhHI.
Unfortunately, there is relatively little experience with such multiple-structure-ground interaction studies.
It thus seems appropriate that a series of studies might be undertaken:
first, analysing each structure alone, i.e.
ignoring the pressure of its neighbors, and then progressively increasing the number of structures taken together.
In the first type of studies one may use fairly detailed models of the superstructure and account for the embedment.
As more and more structures are analyzed
- together, the models of the superstructure would have to become simpler.
Plane-strai n (2-Dimensional) models of selected vertical sections of the plant might also be taken advantage of to gain an (at least qualitative) understanding of the effects of such factors as, for
- example, the different foundation elevations.
At the
- end, when all structures with their exact~plan geometries are taken together, it may be necessary to ignore.the embedment and use the analytical program (CLASSI), i.e. after assuming that the foundations are placer'n the surface.
Finally, careful attention should be paid on properly modeling the rock
profile underlying the plant structures.
Oetermi ning the vari ation of sti ffness with depth i s the key to the success of thi s task.
However, the degree of lateral variability in stiffness should also be given proper consi derati on.
(c)
REGARDING THE USE OF THE AVAILABLE SEISMIC RECORDS:
I consider of utmost importance khecalibration of the various SSI models by comparing their results with the seismic motions recorded the last few years during some distant earthquake events.
Since significant material nonlinearities in the ground are not likely even during strong shaking (because the ground consists mainly of competent rock) the value of such calibration studies cannot be overstated.
However, geometric nonlinearities (e.g.
due to "uplifting")
and material nonlineari ties in the superstructure may develop during the strong design earthquake motions.
The importance of such nonlinearities should be studied independently, in the course of the SSI studies.
Concluding, I would like to suggest that the next Panel-NRC-PG 8
E meet-ingg take place after some analyses have been completed and the results reached the Consultants for careful study.
I would also like to see at the time of this next meeting at least a first compar~sEO~
with the results of recorded motions.
ENCLOSURE 3
A. S. UELETSOS November 26, 1985 BROWN 6, ROOT PROFESSOR
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DEPARTMENT OF CIVIL ENGINEERING, RICE UNIVERSITY
~ HOUSTON, TEXAS 7700l
~ (713) 527-8IOI, EXT. 2388 CONSULTANT ~ 521 I PAISLEY
~ HOUSTON, TEXAS 77096
~ (713) 729-0348 Or. Morris Reich, Head Structural Analysis Division Brookhaven National Laboratory Department of Nuclear Energy Building 129
- Upton, Long Island, NY 11973
Dear Dr. Reich:
Re:
NRC Panel for Long-Term Seismic Soil-Structure Interaction Studies Report titled "Long Term Seismic Program:
Program Plan," January, 1985 Following are my comments regarding Section 7
of the above-designated report on Soil-Structure Interaction (SSI),
preceded by some brief, general coments on the entire report.
Comments on Entire Re ort The proposed program of'tudies is rather comprehensive and ambitious.
It reads almost like a five-year program in earthquake engineering and engineering seismology and, as such, I regard it to be somewhat unrealistic.
I believe that it needs to be better focused to the task at
- hand, and that the entire effort should be directed to issues that are potentially relevant to this task.
recognizing that the final actions are likely to represent a compromise or balance between rationality and practicality.
Comments on Soil-Structure Interaction Studies 1.
The proposed studies on soil-structure interactions impress me as quite reasonable.
- However, here
- again, I
see a
need to identify at the earliest possible date the most important elements of the problem so that they receive the proper attention.
For example, if, as I expect to be the
- case, the consequences of kinematic interaction prove to be considerably more 'mportant in these initial studies than those due to inertial interaction, then the emphasis in the detailed studies should be placed on the kinematic effects.
Or. Morris Rei ch Page 2
2.
Before undertaking any detailed new studies, it would be desirable to re-examine and re-assess the results of all previous studies.
In this context, it would be desirable to know the type of soil-structure inter-action studies that have been conducted so far; how the desiqn.ground motion was specified in these studies; how the structure were modeled; and what were the principal results and conclusions drawn.
It is recom-mended that copies of any available reports on these issues be distributed to the members of the SSI Advisory Panel for their information.
3.
Because of the interdependence of the work on soil-structure inter-action and that relating to the definition of the free-field ground motion groun mo son, close liaison should be maintained between the Advisory Panels for these two topics.
4.
Local topography is likely to be one of the important factors affecting the characteristics of the free field ground motion at the project
- site, and this factor should be provided for.
Insight into the effects of this factor might be gained from analyses of the accelerograms recorded at the plant site and from correlations with appropriate analytical studies, notwithstanding the fact that the recorded motions are of low intensity.
5.
In addition to the proposed SSI studies involving the use of the CLASSI and SASSI computer program, it is recommended that simpler, approxi-mate methods of analysis be employed.
Provided they capture the essential elements of the
- problems, these simpler approaches may be used in the initial stages of the project to make rapid estimates of the effects and relative impo~tance of the multitude of parameters that influence the
- response, and in later
- stages, to help guide the planning of the more elaborate analyses and the interpretation of the resulting data.
The all-too-common tendency of unduly complicating the modeling and analysis of the structure-foundation-soil system and of relying totally on seemingly
- precise, highly complex analyses, should be resisted.
6.
Since the composition and the incidence characteristics of the various waves in the free-field ground motion are likely to be subject to considerable uncertainty, a critical evaluation should be made of the sensst1vity of the resulting foundation motions to possible variations in the free-field wave characteristics.
Dr. Horris Reich Pagd 3
7.
The parametric studies proposed in Section 7.3.5 of the report are hi ghl y impor tant and shoul d consume a
hi gh percentage of the total effort.
It is recommended that these studies be carried out in a step-like
- manner, starting with the simplest possible idealization of the
- problem, and proceeding gradually and systematically to the more complex, realistic representations, buildinq upon the information and insight gained in each step.
8.
In order that I'ay properly execute what I perceive to be my responsiblities on this project, I
consider it essential that there be
.periodic interaction with the groups involved in the detailed studies.
I trust that the mechanism will be established to ensure this.
Yours sincerely, A. S. Veletsos
EPARTflENTOF CIVILENGINEERI THE CITY COLLEGE OF THE CITY UNIVERSITY OF NEW YORK NEW YORK, NEW YORK I 0031-Dr. Norris Reich Head, Structural Analysis Division Department of Nuclear Energy Brookhaven National Laboratory Upton, iong Island, New York 11973 ENCLOSURE 4 212-690-4228 6 January, 1986 Re:
Comments on meeting of 21 October 1985 with SSI Panel on Long Term 5eismic Program for the Diablo Canyon Nuclear Power Plant
Dear Dr. Reich:
This letter summarizes my comments on the presentation made by the DCLTSP Project Team on the proposed program for DCNPP. These comments to some extent echo statements that I have made previously at presentations of the LTSP Project Team.
Firstly, and perhaps most importantly, the S5l phase of the proposed study is to be governed by the results generated from two different computer
- programs, namely, CLAS5I and SASSI.
The CLASSI Code is based upon the analytic approach of Luco and, in its current form, cannot treat the effects of depth of burial, nonhorizontal layering and foundation flexibility. The 5AS5I Code, on the other hand, is a finite element code which is limited by computer size and expense per
- run, as well as the potential effects of the
,nontransmitting bottom boundary.
Various aspects of the problem must therefore be treated by the two different computer programs, with the results-somehow merged to yield the predicted structural responses.
- Normally, comparisons of dynamic responses from two different computer programs is difficult. Comparisons of two different codes treating separate effects differently willmost certainly be difficult.
5econdly, nonlinear effects in the 5SI program cannot be considered t'y either of the computer programs mentioned above. It is not clear how these will be incorporated into the results.
I would therefore recommend that more thought be given of how to assess the effects of nonlinearities arising fro;
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~'otential liftoffan~oniinear structural responses,the 551 caicuiat!cons.
Obviously, if these'Fe significant effects, there may not be any point in conducting complicated SSI calculations for the linear problem. Thirdly, the DC plant site is not a uniform, horizontally bedded site, as is typically considered in SSI calculations.
The effects of the variations in the rock surface on the input ground motions used in the calculations may be as significant on structural response as the SSI effects themselves Considering these comments, my recommendations to the Projec: Te m are as follows:
(a) Prior to the development of the full computer production runs, the Team should present their detailed plans to the SSI Panel for review. These plans should include a discussion of which effect ls to be evaluated by which set of computer runs.
(b) Early in the program, the Team should evaluate whether liftoffis a
concern.
If it is important, it may completely modify the program plan.
(c) Obviously, our SSI panel should closely interact with the Ground Notion Panel, as the adequacy of the inputs generated may be more important to the computed responses than the SSI effects.
Respectfully submitted, Carl J.
stantino Professor of Civil Engineering
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