ML17286B276
| ML17286B276 | |
| Person / Time | |
|---|---|
| Site: | Satsop |
| Issue date: | 07/31/1991 |
| From: | ABB IMPELL CORP. (FORMERLY IMPELL CORP.) |
| To: | |
| Shared Package | |
| ML17286B275 | List: |
| References | |
| NUDOCS 9110170287 | |
| Download: ML17286B276 (34) | |
Text
WIM-3 SEISMIC DESIGN BASIS MODELVALIDATION SOIL VARIATIONSTUDIES Submitted to:
Washington Public Power Supply System 3000 George Washington Way Richland, Washington 99352 Prepared by:
ABB Impell Corporation 5000 Executive Parkway San Ramon, California 94583 Revision 0 July, 1991 9ii0170287 Pii008 PDR ADOCK 05000397 P PDR
TABLEOF CONTENTS Page No.
TABLE OF CONTENTS
1.0 INTRODUCTION
2.0 SOIL VARIATIONANALYSES AND RESULTS 2.1 Variation in Rock Properties 2.2 SSI Analyses and Results
3.0 CONCLUSION
S
4.0 REFERENCES
Total No. of Pages in Report including Cover Page: 21 Page i
1.0 IIVXRODUCTION This submittal presents the results of additional soil-structure interaction (SSI) analyses of the WNP-3 model to address variations in rock foundation material properties. Variations in rock material properties were identified as an open item in NRC 's letter dated February 28, 1991, regarding the Draft Safety Evaluation of the seismic SSI analyses of WNP-3 (Reference 1).
As part of the verification of the adequacy of the WNP-3 in-structure design response spectra, SSI analyses of the WNP-3 nuclear island model were performed using the methodology of the computer program SASSI (Reference 2).
The WNP-3"nuclear island is a deeply embedded rock founded structure, and SASSI offers state-of-the-art capabilities to realistically model embedment, wave scattering, radiation damping and foundation flexibilitySSI effects.
The SASSI analyses of the nuclear island demonstrated that the WNP-3 in-structure design response spectra have an adequate margin of conservatism when compared to the spectra generated using the state-of-the-art methodology of SASSI (Reference 2). The analyses performed in Reference 2 utilized the "Best Estimate" rock material properties, derived from the geotechnical investigations of WNP-3.
As stated in Reference 1, the NRC has concluded that "(WPPSS's) new methodology using state-of-the-art analytical technique (computer program SASSI) for resolving the deconvolution issue is acceptable" and "generally conforms to the requirements of the SRP Sections 3.7.1 and 3.7.2 of NUREG-0800, Revision 2". To satisfy the requirement of Section 3.7.2 of NUREG-0800, Revision 2 (Reference 3) on variation of soil properties, additional SSI analyses are performed using Lower Bound and Upper Bound variations of the rock material properties. The results of these analyses are documented in this report, which is organized in four sections. Section 2.0 presents the analyses and results of the variation study of the rock material properties and Section 3.0 presents the conclusions of this study regarding the adequacy of the WNP-3 in-structure design response spectra. Section 4.0 lists the references cited.
Page 1
2.0 SOIL VACATIONANALYSES AND RESULTS For the soil variation study, analyses with the computer program SHAKE are initially performed in order to determine strain compatible rock properties.
Subsequently, the strain-compatible properties are provided as input to SASSI, which generated the structural response and in-structure response spectra.
Details of the analyses and the results are provided below.
2.1 Variation in Rock Properties Per SRP Section 3.7.2, Revision 2 requirements on variation of rock material properties, Upper Bound and Lower Bound low-strain shear moduli for the rock material are computed as 200% and 50% of the Best Estimate low-strain shear modulus, respectively. Based on these values, the computer program SHAKE generated the strain-coinpatible shear moduli and material damping ratios of the Upper Bound and Lower Bound cases with the SSE ground motion. In the SHAKE analyses, the same shear modulus degradation and material damping curves as in the Best Estimate case are utilized. The results of the SHAKE analyses are tabulated in Table 2.1 below. Strain-compatible shear moduli, shear wave velocities and material damping ratios are listed for all the soil layers of the profile. For comparison purposes, the Best Estimate values are also included (from Reference 2).
Table 2.1- Rock Material Properties:
Lower Bound, Best Estimate and Upper Bound Cases Layer Thickness Shear Modulus Shear Wave Velocity Damping Ratio No. (ft.) (ksf) (ft/sec) (%)
LB HE UB LB HE UB LB HE UB 1 27.5 27670 60912 111776 2618 3884 5262 1.3 1.0 0.8 2 31.0 24434 60283 99848 2460 3865 4973 2.0 1.5 1.3 3 25.0 29441 59742 120810 2700 3845 5470 2.1 1.8 1.4 H 33684 59000 138883 2889 3823 5865 2.4 2.0 1.7 H=Halfsp ace LB=Lower Bound BE=Best Estimate UB=Upper Bound Page 2
R2 SSI Analyses and Results As in the Best Estimate case, two-dimensional SSI analyses are performed for the Upper Bound and Lower Bound soil cases using the computer program SASSI (Reference 4). Seismic motions are applied in two directions:
~ Horizontal (E-W), and
~ Vertical The WNP-3 E-W horizontal building model is used in the horizontal analyses and the vertical building model is used in the vertical "analysis. Both models (horizontal and vertical) are identical to the models used in the Best Estimate case. As in the case of the Best Estimate soil profile, the control motion was applied at the surface of the free field.
Response spectra with 2 percent damping ratio are generated at the following locations (refer to Figure 2.1 for location):
~ Top of Shield Building (Node No. 1 in Figure 2.1)
~ Top of Reactor Auxiliary Building (Node No. 23 in Figure 2.1)
~ Top of Containment Vessel (Node No. 31 in Figure 2.1)
~ Top of Internal Structures (Node No. 51 in Figure 2.1)
~ Center of Basemat (Node No. 62 in Figure 2.1)
Figures 2.2 to 2.11 present the plots of the response spectra according to the numbering sequence that follows. Each figure contains the Upper Bound and Lower Bound spectra as well as the Best Estimate and the Design spectra, for comparison purposes.
Figure No. Direction Location 2.2 Horizontal Top of Shield Building 2.3 Horizontal Top of Reactor Auxiliary Building 2.4 Horizontal Top of Containment Vessel 2.5 Horizontal Top of Internal Structures 2.6 Horizontal Center of Basemat 2.7 Vertical Top of Shield Building 2.8 Vertical Top of Reactor Auxiliary Building 2.9 Vertical Top of Containment Vessel 2.10 Vertical Top of Internal Structures 2.11 Vertical Center of Basemat In addition, the free-field motions at the foundation level corresponding to the Upper Bound and Lower Bound soil cases for the horizontal and vertical directions were generated and they are plotted in Figures 2.12 and 2.13, respectively. The free-field surface motion is superimposed in the same plot for comparison purposes.
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il The spectral plots demonstrate that the response of the WNP-3 model in the Upper Bound case is the highest, while that of the Lower Bound case is the lowest. The most important factor influencing the response pattern observed is the magnitude of the respective free-field motion at the foundation level (Figures 2.12 and 2.13).
The Upper Bound case provides the highest ground motion at the foundation level, while the Lower Bound motion is the lowest at that level.
Due to the high stiffness of the rock material (even in the Lower Bound case), the fundamental SSI frequency at each location is approximately the same for all three cases (Upper Bound, Lower Bound and Best Estimate). Therefore, the Upper Bound case completely envelopes the response of the other two cases.
Furthermore, it is observed that, in general, the design spectra envelop or are very close to the SASSI spectra for all the cases and at all frequencies. Minor exceedances occur in the vertical direction at three locations, Top of Containment, Top of Internal Structures and Center of Basemat, which are judged to be insignificant for design applications. At the Top of Internal Structures and Center of Basemat the exceedances occur in the 1-2 Hz frequency range, which is a low range for response of systems in the vertical direction. At the Top of the Containment, and only for the Upper Bound case, the SASSI spectra exceed the design spectra around 15 Hz. This is also judged to be of no significance to the design spectra, since the Upper Bound case is associated with rock shear wave velocities greater than 5000 ft/sec, which are well out of the range of the velocities recorded by the geotechnical investigations at WNP-3.
Page 4
1 Mass Point Flexible Beam Shield Building 605.80 Containment Vessel Rigid Beam 31 595.52 Z (Vertical) 595.34 579.27 0 31 32 575.00 X (East-West) 32 33 555.00 552.90 33 531.70 524.43 503.60 35 505.00 35 Reactor Auxiliary
'Internal 36 Building 475.50 Structure 23 474.00 36 455.00 51 24 51 447.40 443.00 428.69 441.00 52 37 24 204 52 425.00 53 38 425.00 25 419.30 389.00 53 395.00 38 25 416.50 Grade 54 13 39'l.20 383.50 54 400.10 39 389.00 I 'l0 55 26 I 377.50 I I 40 380.00 I I Q10 363.27 57 I I
I I 58 I I 11 357.00 372.00 I I 362.20 11 205 I 14 I 41 I I I 349.00 I 351.00 12 136 I 361.50 I 213 I I 342.00 60 I
I I
I I I 12 61 I 335.00 137 W
330.50 I I 330.50 I16 22 30 44 47 50 62 69 78 105 '108 134 138 )
Primary Structures with Foundation (All elevations in Feet)
Figure 2.1 - Structural Model of VQM-3 Page 5
Top of Shield Building, 2/o Damping, EW Component 24.0 Lower Bound SASSI 20.0 Uppor Bound SASSI Best Estimato SASSI 10.0 - - - Dosign 5 12.0 R
5 I 0.0 I
4.0 I
e 0.0 1.0 2.0 5.0 10 20 50 FREQUENCY(Hz)
Figure 2.2 - Horizontal In-Structure Response Spectra WPPSS WNP-3 Top of Shield Building Page 6
I Top of Reactor Auxiliary Building, 2/o Damping, EW Component 1 2.0 1 I I 1 Lower Bound SASSI Upper Bound SASSI I I
Best Estimate SASSI I
- -- - Design I
I I
I I
8.0 1 I
I I
I I
I I
I
.l.o I I
I I
/I \
I 0.0 1.0 2.0 10 20 FREQUENCY (Hz)
Figure 2.3- Horizontal In-Structure Response Spectra WPPSS WNP-3 Top of Reactor AuxiliaryBuilding Page 7
Top of Containment Vessel, 2/o Damping, EW Component BO.O Lowor Bound SASSl Uppor Bound SASSl Best Estimato SASSI
-- -- - Design 32.0 8 I
\
8 100 4 I
-b 1
I 1
1 I 1 1
0.0 1.0 2.0 3.0 10 20 FREQUENCY (Hz)
Figure 2.4 - Horizontal In-Structure Response Spectra WPPSS WNP4 Top of Containment Vessel Page 8
0 I
Top of Internal Structure, 2/o Damping, EW Component 1 2.0 Lower Bound SASSr Lrppor Bound SASSr Bost Estimate SASSI
- - - - Design 0.0 I I
I I I I
I I
I I I I
Q I I
8 4.0 I I
I I
'I 0.0 1.0 2.0 5.0 10 20 FREQUENCY (Hz)
Figure 2.5- Horizontal In-Structure Response Spectra WPPSS WNP-3 Top of Internal Structures Page 9
Center of Basemat, 2/o Damping, EW Component Lowor Bound SASSI Uppor Bound SASSI Best Estimate SASSI Dosign r
I I
\
I I I
I I I I 'I I \
I I I \
8 S.O 44 '
I I 0.0
~ .0 2.0 S.O IO SO FREQUENCY (Hz)
Figure 2.6- Horizontal In-Structure Response Spectra WPPSS WNP-3 Center of Basemat Page 10
Top of Shield Building, 2/o Damping, Vertical Component 12.0 Lowor Bound SASSI Upper Bound SASSI Best Estimato SASSI-
- Dosign I I
I 8.0 V" I
I I I I I
I
/ I
/ I I
I 8 4.0 "I I *I 0.0 1.0 S.O ~ 0 20 $0 FREQUENCY (Hz)
Figure 2.7- Vertical InNtructure Response Spectra WPPSS WNP4 Top of Shield Building Page 11
Top of Reactor Auxiliary Building, 2/o Damping, Vertical Component 3.0 I I I
Lower Bound SASSI I I I I Upper Bound SASSI I I I
I 1
I Best Estimate I I I
- - - - Design I I
I 2.0 I I I I I I I I
I I I I 1
I 1
1 C3 I Q 1.0 I I
0.0 1.0 2.0 5.0 10 20 50 FREQUENCY (Hz)
Figure 2.8- Vertical InWtructure IRsyonse Spectra WPPSS WNP-3 Toy of Reactor AuxiliaryBuilding Page 12
Top of Containment Vessel, 2/o Damping, Vertical Component 0.0 ~ I Lowor Bound SASSI Uppor Bound SASSI Bost Estimate SASSI
- - -- - Design 4.0 I I I
I I I I
I I I
0.0 1.0 2.0 S.O 10 20 SO FREOUENCY (Hz)
Figure 2.9- Vertical InoStructure Response Spectra WPPSS WNP-3 Top of Containment Vessel Page 13
Top of Internal Structure, 2/o Damping, Vertical Component 3.0 Lower Bound SASSI Upper Bound SASSI Best Estimate SASSI
- - -- - Design 2.0 8 I I
J 1.0 I
I d I
0.0 1.0 2.0 5.0 10 20 50 FREQUENCY (Hz)
Figure 2.10- Vertical In-Structure Response Spectra WPPSS WNP-3 Top of Internal Structures Page 14
Center of Basemat, 2/o Damping, Vertical Component 0 r Y Lower Bound SASSI Upper Bound SASSI Best Estimate SASSI
- -- - Design 2.0 I
I I
I 1.0 e" I
I I
/I 0.0 1.0 2.0 S.O 10 20 FREQUENCY (Hz)
Figure 2.11- Vertical IneStructure Response Spectra WPPSS WNP4 Center of Basemat Page 15
j V -~
Free Field Motion, 2/o Damping, EW Component 3.0 I \ P I I 'r 'V Lower Bound, Foundolion Level Upper Bound, Foundodon Lovel
- - -- - Surface 2.0 I~
'l I ' I
'll I I
~ I I
~ ~
\
0.0 1.0 2.0 3.0 10 50 FREC)UENCY (Hz)
Figure 2.12- Horizontal Free-Field Response Spectra WPPSS WNP4 Page 16
Free Field Motion, 2/0 Damping, Vertical Component 0.0 ~ -~ p Lower Bound, Foundalion Lavol Uppar Bound, Poundaiion Laval
- - - - - Surface 2.0 8 i.0 I
0.0 1.0 2.0 5.0 10 20 50 FRECIUENCY (Hz)
Figure 2.13- Vertical Free-Field Response Spectra WPPSS WNP4 Page 17
', ~
t
. I IE
3.0 CONCLUSION
S Soil variation studies are perofrmed for the WNP-3 model. The rock shear moduli were varied by 50% and 200%, according to the recommendations of the SRP Section 3.7.2, Revision 2, and additional SASSI analyses are performed with Upper Bound and Lower Bound rock properties. Using the results of these analyses, Upper Bound and Lower Bound response spectra are generated at selected locations. The resulting Upper Bound and Lower Bound response spectra as well as the Best Estimate spectra are, in general, enveloped by the design spectra by an adequate margin. Minor spectra exceedances are of no significance to design applications.
The state-of-the-art methodology of SASSI combined with the soil variation studies satisfy all SRP Section 3,7.1 and 3.7.2 requirements on SSI analyses and response spectra generation. Therefore, the SSI analyses performed for the WNP-3 structural model demonstrate that there is ample conservatism in the WNP-3 design spectra.
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h~ ~
4.0 Letter from Marvin Mendonca, USNRC, to D. W. Mazur, Washington Public Power Supply System, dated February 28, 1991,
Subject:
NRC Review of the Soil-Structure Interaction (SSI) Analysis/Deconvolution Issue for WNP-3.
- 2. Impell Corporation, Calculation WNP3-01, "WNP3 2D SASSI SSI Analysis", Revision 1, August, 1988.
- 3. U.S. Nuclear Regulatory Commission, Standard Review Plan, NUREG-0800, Revision 2, 1989.
4 ABB Impell Corporation, Standard Computer Program SASSI, Version 4.0 (Cyber 990), User's Manual Revision l.
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