ML17332A585
| ML17332A585 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 02/28/1995 |
| From: | INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG |
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| References | |
| AEP:NRC:1082K, NUDOCS 9502280023 | |
| Download: ML17332A585 (87) | |
Text
ATTACHMENT 3 TO AEP:NRC:1082K Donald C. Cook Nuclear Plant Individual Plant Examination for External Events Revised Seismic Probabilistic Risk Assessment 9~02280023 9sp~iQ PDR ADQt K 05000315 PDR
DONALDC. COOK NUCLEARPLANTUNITS I AND 2 ADDENDUMTO SEISMIC PROBABILITYRISK ASSESSMENT NOTEBOOK FEBRUARY 1995 REVISION 0 Preparer
Date Date d (AEPSC Section nager)
Date
NOTE This notebook was prepared in accordance with the applicable sections of 10 CFR 50, Appendix B, "Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants."
The documentation and the analysis reported in this notebook utilized guidance information, design and plant information contained in reference documents applicable to Donald C. Cook Nuclear Plant Units 1 and 2. A list of these references is presented in this notebook.
DONALDC. COOK NUCLEAR PLANT ADDENDUMTO SEISMIC PROBABILISTICRISK ASSESSMENT TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES
1.0 INTRODUCTION
2.0 METHODOLOGY fv 2.1 SELECTION OF COMPONENTS FOR REEVALUATION 2.2 REVISED FRAGILITYANALYSIS 2.3 PROBABILITYOF A SEISiiIIC EVENT IN EACH SUBINTERVAL 3
2.4 SEISMICALLYINDUCED INITIATINGEVENT FREQUENCY DETERMINATION 4 2:5 SEISMIC CORE DAMAGEFREQUENCY CALCULATION 3.0 RESULTS AND CONCLUSIONS 3;I
SUMMARY
OF RESULTS 3.2 COMPARISON TO ORIGINALANALYSIS
4.0 REFERENCES
APPENDICES APPENDIX A - WESTINGHOUSE FRAGILITYANALYSIS APPENDIX B - SEISiilC INITIATPfGEVENT QUAN'I'IFICATIONFOR EACH EVENT TREE APPENDS C - QUANTIFICATIONOUTPUT FOR SEISMIC CORE DAi>IAGEFREQUENCY APPENDED D - CORRECTION OF SEISiiIIC CORE DAMAGEFREQUEiNCY AND RISK REDUCTION RANKINGS FOR HIGH CONDITIONALFAILURE SEISiMIC SUBINTERVALS Bi
DONALDC. COOK NUCLEAR PLANT SEISiiIC PROBABILISTICRISK ASSESSMElfl'IST OF TABLES TABLE DESCRIPTION 1
REVISED SEISMIC FRAGILlTYPARAMETERS FOR LIMlTEDEVALUATION COMPONENTS PAGE 8
SEISiMIC ACCELERATIONLEVELPROBABILITIES (COOK SITE)
SEISMIC FRAGILITYPAtuddETERS STANDARDDEVIATIONSFROM MEDIAN STRUCTURE AND COMPONENT FAILUREPROBABILlTYFOR EACH SEISMIC INTERVAL NORMALERROR LOOKUP TAKE BASIC EVENT SEISMIC FAILURERATES EVENT TREE NODE SEISiilC FAILURERATES 12 16 20 24 25 27 9
SEISMICALLYINDUCEDINI'HATINGEVENT FREQUENCIES BY SEISiMIC INTERVAL28 10 SEISiiIC CORE DAMAGEFREQUEN'ES l
11 BASIC EVENT CONTRIBUTIONTO CORE DAMAGEFREQUENCY 29 30
FIGURE DESCRIPIION DONALDC. COOK NUCLEARPLANT SEISMIC PROBABILISTICRISK ASSESSMENT LIST OF FIGURES PAGE SEISMICALLYINDUCEDSiLLANDMEDIUMLOCA PROBABILITIES 31
I+>>
a
ADDENDUMTO SEISMIC PROBABILITYRISK ASSESSMENT NOTEBOOK
1.0 INTRODUCTION
During the July 1994 NRC audit of the Seismic PRA (Reference 1), the NRC cited two related concerns with the Seismic PRA for the Cook Nuclear Plant (Reference 2). First, the seismic fragility analysis was performed with a technique that was not standard ln the industry (Reference 3 was cited as an example of the preferred technique).
The techniques used In Reference 2 tend to lead to lower median fragilities, with limited randomness and no uncertainty factors utilized. Using these techniques was considered by the NRC to introduce the potential for an improper ranking of seismically important contributors.
The second issue had the same potential impact on the proper ranking of important risk contributors.
When the seismically induced event trees were analyzed, the seismic intervals chosen In Reference 2 were considered to be too broad, masking detail needed for a proper ranking. This resulted in seismic interval 2 (.25 to.50g) having nearly 100% failure, while the previous seismic interval 1 nearly none.
This addendum follows the methodology of the original analysis to correct these two problems, but in this case using the preferred fragility calculation methods for select structures and components and smaller seismic quantification intervals.
First, the most critical structures and components are chosen.
Complete, new fragilities for these structures and components were developed by Westinghouse using the industry standard methodology. Additional striictures and components were selected for a partial reevaluation.
Using these new fragilittes, the seismic core damage frequency was calculated using the original methods.
This time, however, Interval 2 Is broken into five subintervals and interval 3 into three subintervals to provide greater detail. The new results are then analyzed, and a new ranking of seismically important components fs developed.
2.0 MEXHODOLOGY 2.1 SELECTION OF COMPONENTS FOR REEVALUATION For the purposes of probabilistic risk assessments, seismic fragility parameters are developed by examining the conservative design basis seismic response analysis, and removing that conservatism by multiplying the design, basis acceleration for failure by factors representing the level of conservatism.
This technique is explained in more detail In the original analysis.
Each factor has an associated randomness and uncertainty, and each factor represents the level of conservatism in one aspect of the design basis calculation.
Typical factors are associated with materials properties, modeling techniques, and seismic damping.
In the original Westinghouse fragility analysis, Westinghouse chose to conservatively calcuhte the margin factors.
Since these were conservatively calculated, there was no uncertainty, and the uncertainty factor was set to zero. In a related fashion, the randomness factor could be underestimated or neglected by a conservative choice of a margin factor.
Given that the Westinghouse fragility calculation appears to be conservative, the high confidence of low probability of failure (HCLPP) calculated using the original Westinghouse fragilities should be either similar to or conservative to the HCLPF calculated by the more standard techniques.
Since seismic interval 2 (.25 to.50g) ls of primary interest, and the HCLPF represents only a 5% failure rate, reevaluating fragilities for components that have HCLPFs of less than.6g using the original Westinghouse techniques was selected In order to capture all significant contributois.
To limitthe amount of reanalysis, only those structures and components with originally calculated HCLPFs of.40g or less are chosen for a complete reevaluation.
These willfail earlier than the other components, and are more likely to be the dominant contributors.
As will be seen, two margin factors that were not considered in the original evaluation are applicable to large sets of components.
These margin factors account for interaction between the major structures and the soil and for the estimated of the seismic spectra. They are applied to those components whose HCLPFs fell in the range of.40 to.60g or were otherwise not the limiting failure mode for a structure or component to ensure that appropriate seismic rankings in that interval are obtained.
The choice of HCLPF as a selection criteria for reevaluation is confirmed in the next section.
By comparison of a large selection of HCLPFs calculated by the two methods, the HCLPFs were found to be approxiamtely the same.
Therefore, structures and components with HCLPFs above.Sg by the original Westinghouse method would not become a contributor to failure in seismic interval.2 iftheir fragilities were reevaluated.
Ik
~
~
c
)
1 The similarity of the HCLPFs for the two methods can be JustiTied on a qualitative basis.
The original fragility analysis was based on the selection of conservative margin factors with no
~uncertainty, When best estimate margin factors were selected for the current fragility analysis, uncertainty parameters were Included.
The value of the best estimate margin factor at the lower extreme of the uncertainty range should also be a conservative margin factor. It would not be unreasonable for a conservative margin factor and the conservative end of a best estimate margin factor with uncertainty to be similar. Since the fragility evaluation is based on a combination of these margin factors, again, it is not unreasonable for the HCLPFs of the two methods to be similar.
A quantitative proof of this argument would require a detailed evaluation of the methodology used for each margin factor, over all ranges of the application of those methods. Given the close comparison of the HCLPFs of the selection of structure and components that was already performed, and the fact that the selection was based on those structures and components that were most likely to impact the seismic analysis result, we believe that this detailed evaluation is unwarranted.
2.2 REVISED FRAGILlTYANALYSIS The purpose of the fragBity analysis is to establish approximate estimates of fragility parameters for use in the SPRA analysis using simplified conservative approaches.
For the components selected by the method described above, Westinghouse reevaluated the seismic fragility using the methodology developed at Diablo Canyon (Reference 3). This reevaluation has removed conservatism, and added increased randomness and uncertainty variation in the form of beta factors.
The results are presented in Reference 4, (attached as Appendix A).
As can be seen in Appendix A, the HCLPFs for the 11 structures and components reevaluated using the Diablo Canyon techniques are very similar to the HCLPFs originally calculated by Westinghouse.
The median failure values increased significantly for all reevaluated structures and components.
Note that the fragilities for piping supports at the component cooling water outlet were not reevaluated.
The limitingpoint in the original calculation was the snubbers.
Most of the snubbers at this location are being replaced by struts (which typically have more margin to failure than snubbers) as a part of the snubber reduction program (Reference 5).
Since the design is not complete, and more margin is expected in the new design, this component is neglected in this analysis.
In the new Westinghouse evaluation (Reference 4), Westinghouse had Riuo 8c Associates develop a set of margin factors for building response to an earthquake, taking credit for soil structure interaction.
This led to margin factors and associated uncertainties for major structures and
components in these buildings.
Since these margin factor were not considered in the original evaluation of the structures and components with HCLPFs in the.40 to.60g interval or were otherwise not the limitingfailure mode for the structure or component (Reference 6), these factors were selected and applied to the result of the original Westinghouse fragilities the components selected.
In addition, a spectral margin factor was used In the Westinghouse reevaluations.
This margin factor compares the LLNLspectral shapes to the Cook specific spectral shapes, establishing margin for each piece of equipment based on its response frequency.
Since this was already calculated for each component in the original analysis as part of the sensitivity study, this margin factor Is also applied here to these components (References 8 and 9). The results are listed in Table 1.
The seismic failure frequency of each structure or component for each seismic subinterval Is now calculated.
First, equation 3 of the original analysis Is solved for each structure or component.
This gives the number of standard deviations from the subinterval midpoint to the median fragility. The failure frequency Is then determined assuming that the failure rate is normally distributed about the median.
This was performed in a spreadsheet developed for this purpose.
Table 3 provides a listing.
of the current fragility parameters (both original and revised) and Table 4 the standard deviation to the median for the subinterval.
Table 5 shows the look up table result of failure frequency given the standard deviation.
For reference, the lookup table is shown in Table 6, which used values chosen from Reference 10.
'he spreadsheet was also used to associate each of the structure or component failure probabilities calculated on Table 5 with the seismic basic event identifier used as innut to the quantification codes.
Table 7 provides a IIst of the basic event fdentifiers, the Table 5 line numbers which contribute to the failure rate of the basic event, and the failure rate in each subinterval.
When more than one Table 5 failure rate contributes to a basic event failure rate, and the magnitude is large, Boolean summation techniques are used.
Table 8 uses the same technique as Table 7 to develop the event tree nodes used in determination of the initiating event frequencies.
In addition, small and large break LOCA initiating event frequencies are taken from Figure 1 (Reference 11).
2.3 PROBABILITYOF A SEISiMC EVENT IN EACH SUBINTERVAL The methodology of the original notebook, Section 2.3, is followed here.
First, the original seismic interval 2 is broken into 5 subranges, labeled here 2a to 2e, Interval 3 is broken into three subintervals labeled 3a to 3c. The p'robability of having a seismic event exceeding the given acceleration for each of those intervals and the midpoint of each Interval Is then calculated.
To calculate the probability of exceedance at each subintervai boundary, an exponential curve fit was developed for the two known points at.25 and.50 g (2.09E-5/year and 1.47EA/year, respectively),
giving the equation.
p = 2.97 E-04 e'ince the overall seismic initation frequencies in Interval 3 are small, less accuracy Is required in interval 3, and this fit is used for this interval as well. This equation was solved for each subinterval boundary, and the probability of a seismic event in that subinterval was calculated by subtraction.
Table I provides a summary of the results.
2.4 SEISiMICALLYINDUCED INITIATINGEVENT FREQUENCY DETERMINATION This section uses the analysis and method of Section 29 of the original analysis.
The probability of failures that could Initiate a modeled event is calculated for each subinterval on Table 8, as described in Section 2.2.
These base Initiating event frequencies correspond to the nine failure groups found in Section 2.3 of the original analysis.
The SUPER5 (Reference
- 12) event tree quantification was performed for the five subintervals, resulting In final, hierarchically ranked, initiating event frequencies.
These initiating event frequencies are shown in Table 9 for both normal and loss of offsite power cases.
As the seismic acceleratIon Increases, the more severe accident initiators become relatively more significant, reducing the fractional contribution of the less severe accident Imtiators.
2.5 SEISMIC CORE DAi~GE FREQUENCY CALCULATION The seismic quantiTicatlon process described in Section 2.6 (and developed in Sections 2.4 and 2.5) of the original notebook was performed for the eight seismic subintervals.
The Input needed for this Is the basic event failure rates of Table 7, the initiating event frequencies of Table 9, and the normal random failure rates (revision 0 analysis values were used for consistency, Reference 13). The core damage frequency result for this analysis is found in Appendh C.
By comparing the initiating event frequencies to the event core damage frequency in AppendL< C, it can be seen that some event core damage frequencies approximate or exceed the initiating event frequencies.
This is due to the use of a cutset editor type code rather than a full quantification. To
'orrect for this, the top cutsets for each event are summed in a Boolean fashion to obtain the correct core damage frequency and reduction in risk for each top contributor result.
This correction is performed for subintervals 2e through 3c. The corrected core damage frequencies are summarized on Table 10. Table 11 summarizes the core damage frequency contribution of each significant component in each subinterval, In the form of reduction Ifcore damage frequency Ifthe component were not to fail.
3.0 RESULTS Ai~ CONCLUSIONS The Cook Nuclear Plant-speciTic seismic hazard curves and fragility analysis results were Incorporated into the seismic accident sequence models.
The seismic accident sequence quantification was performed for the "normal power available" cases and for the "loss of offsite power" cases, where these two cases reflect whether offsite power Is expected to be available immediately following a seismic event.
r The results of the accident sequence quantification were combined with the initiating event frequencies for those events which were not specifically quantified (i.e., paths leading to direct core damage - "C1" cases).
Table 10 presents the results of the seismic PRA analysis.
The results are presented based on each seismic Interval and as a total seismic core damage frequency.
As shown in Table 10, the seismic core damage frequency is estimated to be 3.17'/yr. The LOSP cases in seismic interval 2 dominant the core damage frequency.
To further define which components, equipment, and buildings are dominating the results, Table 11 offers a summary listing of the importance analysis results.
As can be seen from this table, the dominant contributors to seismic core damage are:
1.
AuxiliaryBuilding 2.
Loss of Electric Power Systems a.
600 VAC Transformers b.
Diesel Generator Fuel Oil Day Tank 3.
Turbine-Driven AF Pump (random failures)
To a lesser degree, the following are also shown as contributors:
1.
250 VDC System 2.
Reactor Protection System Failures (Misc. Panels) 3.
Ice Condenser Appendix C provides detailed listings of the top cutsets which contribute to the total seismic core damage frequency.
As can be seen from Table 10, the Initiating events which dominant the analysis are:
I.
Direct Core Damage (e.g. unrecoverable damage, dominated by containment structural failure)
And of relatively equal magnitude 3a.
Steamline/Feedline Break 3b. Loss of Service Water System 3c.
Large LOCA 3.1
SUMMARY
OF RESULTS The Cook Nuclear Plant results and dominant contributors are comparable and consistent with those reported in other seismic PRAs (see Reference 14 - NUREG/CR4334).
This section provides a discussion and explanation of the Cook Nuclear Plant Seismic PRA accident sequence results presented in Table 10. Approximately 80% of the CDF comes from 2 initiating events.
The top contributor is loss of offsite power at 60% followed by direct core damage at 19 lo.
Since the seismic analysis is broken Into subintervals, and the manual correction was needed to properly determine the rankings of the significant contributors, the screening criteria set forth in NUREG-1335 (Reference
- 15) are not rigidly followed. Each of the criterion is described below.
Screenin Criterion I This criterion requires that any systemic sequence that contributes 1E-7 or more per reactor year to core damage" be identified. Since the seismic core damage frequency is so low, the dominant failures
are Usted on Table 11 down to 1.E4/yr.
Screenin Criterion 2 This criterion requires that "all systemic sequences within the upper 95 percent of the total core damage frequency" be identified. These are the failures listed on Tables 10 and 11.
Since these are calculated as a risk reduction, the damage frequencies do not sum to near the total core damage frequency.
(Ifany risk significant component was to be strengthened so that it would not fail, the risk reduction value of other components would increase).
Screenin Criterion 3 This criterion requires that "all systemic sequences within the upper 95% of the total containment failur'e probability" be identified.
According to the fragility data, seismic failure of the containment building may occur due to the following causes:
failure of the containment rebar or failure due to soil pressures.
Of these two failure mechanisms, the soil pressure dominates.
Failure of the containment structure was designated as direct damage in Table 10. The sum of the direct damage events for all the seismic intervals is calculated to be 6.08E-07/yr which is approximately a 20% contribution to the total seismic core damage frequency.
However, this value represents seismic containment failure and not a containment failure probability after containment Is challenged following an accident.
A seismic Level II containment performance is not required for the IPEEE (GL 88-20 Supplement 4), but containment performance is assessed as follows using analogies to the internal events Level II analysis.
The dominant contributors listed in Table llare examined to determine the type of potential containment failure which exists. Failure is dominated by failure of the auxUiary building or electric power sources.
These would fail containmert spray as well. Based upon the internal events Level II results, core damage, in general, is expected to occur in the range of 2-to-4 hours after accident initiation ifdecay heat removal is lost.
As for containment performance, containment spray failure greatly reduces the availability of water cooling on the failed core in the containment reactor cavity after vessel failure. With less water in the cavity, containment pressurizes at a much slower rate due to less steaming from the failed core and containment failure occurs much later in the accident.
Some sequences failed due to ice condenser failure. The ice condenser was not modeled within the internal events analysis due to Its high availability, thus no analogies can be drawn.
However, with Cook Nuclear Plant being an Ice condenser containment plant, chances of containment failure following an accident significantly increase after losing the ice condenser and containment failure could occur sooner in an accident.
After containment failure, any water inside containment may boil off, thereby preventing ECCS from removing decay heat via recirculation mode, which would lead to core damage.
Screenin Criterion 4 This criterion requires that "systemic sequences that contribute to a containment bypass frequency in excess of 1E-8 per reactor year" be identified.
For the seismic PRA, containment bypass is assumed ifthe Reactor Protection System/Engineered Safeguards Features Actuation System (RPS/ESFAS) fails (e.g., signals fail to isolate the containment).
The seismic PRA does not differentiate between signals for containment isolation and signals for ESFAS actuation; thus, the results reported here are conservative.
Note that even ifthe
RPS failure represents component actuation, it could be anticipated that containment cooling systems such as the containment spray system would fail to start, thus eventually leading to a containment bypass failure event.
The RPS/ESFAS is represented in the seismic PRA by a basic event referred to as "Miscellaneous Panels."
As presented in Table 11, failure of the miscellaneous panels (RPS/ESFAS) is a significant contributor. RPS failure contributes 4.7E-8/yr to core damage frequency.
3.2 COMPARISON TO ORIGINALANALYSIS The current analysis estimated the total core damage frequency as 3.17E-6/year, an 80% reduction from the original analysis value of 1.83E-5/year.
This is primarily due to the conservatism that was removed from the seismic fragility calculations.
However, the ranking of significant components is very similar. The failures of the auxiliary building and electric power systems dominate both analyses.
The original analysis identified the turbine building pedestal and 4kV switchgear failures as being lesser significance, and these were not Identified in the current analysis.
No new significant contributors were identified in the current analysis.
For initiating events, the current analysis is dominated by loss of station power and direct core damage, with lesser contributions from steamline break, loss of essential service water, and large LOCA. The original analysis identified all of these except for the more severe Initiators of direct core damage and large LOCA. This Is attributed to the overall lower core damage frequency of the current analysis, making the more severe initiators relatively more Imrertant.
In conclusion, even with different fragility calculation methods and the resulting overall differences in core damage frequency, the rankings of significant seismic failure contributors Is very similar for the two analyses.
4.0 REFERENCES
1.
NRC Site Audit for the Cook Nuclear Plant IPEEE, Exit meeting ofJuly 28, 1994.
2.
"Donald C. Cook Nuclear Plant, Seismic Probabilistic Risk Assessment Notebook", April 1992.
3.
"Seismic Fragility of Civil Structures and Equipment Components at the Diablo Canyon Power Plant," Report No. 1643.02, NTS Engineering, 1988.
4.
Westinghouse Letters AEP-94-760, "Fragility Parameter Review" (8/16/94); AEP-94-785 "Transmittal of Fragility Data (9/23/94); and AEP-94-789 "Supplementary Seismic Fragility Estimates" (10/3/94).
t II 5.
AEPSC Memo, D. Petro to R. Bennett, Calculated Design Loads (DC-D4620.5), Dated October 4, 1994.
6.
Westinghouse Electric Corporation, "Seismic Fragility Assessment - Donald C. Cook Nuclear Plants," February 1992.
7.
8.
Westinghouse letter AEP 94439, "Transmittal of FragOity Calculations," dated November 16, 1994, Calculation CSE 09-94-0046.
I Westinghouse Calculation AEP49, "Fragility Data, LLNLUHS Spectral Shape".
9.
'Westinghouse Calculation AEP-50, "LLNLUHS Equipment Fragility Data".
10.
Rizzo Associates Letter "Seismic Hazard Analysis, Donald C. Cook Nuclear Plant," 8/17/94.
I 11.
M.P. Bohn, et. al., "Analysis of Core Damage Frequency: Surry Power Station, Unit 1 External Events," NUREG/CRA550, also SAND86-2084, Vol. 3, Rev. 1, Part 3, December 1990 and NUREG/CR 3428, "Application of the SSi~ Methodology to the Seismic Risk at the Zion Nuclear Power Plant", November 1983.
12.
"SUPER Code System User Manual for Version 2.0," WCAP-12401, Westinghouse Electric Corporation, Westinghouse Proprietary Class 2, September, 1989.
13.
"Donald C. Cook Nuclear Plant, Individual Plant Examination Summary Report", April 1992.
14.
R. J. Budnitz, et al, "An Approach to the Quantification of Seismic Margins in Nuclear Power Plants," NUREG/CRA334, 1985.
15.
NUREG-1335, "Individual Plant Examination; Submittal Guidance," U.S. Nuclear Regulatory Commission, 1989.
16.
CRC Standard Math Tables, 10th Edition.
I Table 1 - Revised Seismic Ti hameteas for Limited Evaluation Com nents
~Com onenl Screen House
~ori inol Br Bu B
Revised Am Br Bu B
- Reinforced Concrete >Valls fl]
- Columns/Shear Failure
[1]
Auxiliary Building
- Foundation Mat
[2]
- Concrete Structure f2]
Turbine Pedestal
- Columns - Bent I, XII
[2]
- Columns - Bent II, XI f2]
- Columns - Bent III,IV, IX, X [2]
- Columns - Bent VI, VII
[2]
Containment
- Soil Pressure Ice Condenser
- Top Deck Structure
[4]
- Ice Baskets
[4]
- Lower Support Structure
[4]
- Lattice Frame, Cradles and Columns
[4]
- Phase Link f4]
RCS Primary Components
- Upper Internals '5]
ECCS Pumps
[6]
0.09 0.00 0.09 0.14 0.00 0.14 0.12 0.00 0.12 0.12 0.00 0.12 0.12 0.00 0.12 0.12 0.00 0.12 0.31 0.00 0.31 0.11 0.00 0,11 0,20 0.00 0.20 0.11 0.00 0.11 0.39 0.00 0,39 0.39 0.00 0.39 0.14 0.00 0.14 0.05 0.00 0.05 0.16 0.00 0.16 0.31 0.00 0.31 0.62 92 0.72
.42 0.41
.29 0.38
.31 0.51
.30 0.54
.30 0.53
.30 0.50 0.99
.42 0.52
.30 0.66
.34 0.51
.30 0.91 AS 0,87
.48 0.65
.42 0.49
.28
.27
.27
.27
.27
.27
.27
.27
.27
.27
.27
.27
.27
.27
.27
.20
.42
.50
.40
.41
.40 AO
.40
.40
.50
.40 A3
.40
.55
.55
.50
.35 1.27 1.48
.98
.91 1.22 1.30 1.27 1.20 2.24 1.41 1.80 1.39 2A8 2.37 2.24
.83 RHR Heat Exchanger
[6]
0.10 0.00 0.10 0.53 30
.20
.36
.76 Diesel Generator
- Switchgear 600V Containment Spray 0.10 0.00 0.10 0.66
.30
.20
.36 1 20
Table 1 (Cont'd)
Revised Seismic Fragility Parameters for Limited Evaluation Components
- Pumps
- Heat Exchanger Reactor Protection System 0.05 0.00 0.10 0.00 0.05 0.10 0.49 28 20 0.40 30 20
.35
.96
.62
- RPS/Aux Rack/STC
[6]
0.05 0.00 0.05 0.47
.28
.20
.79 per Reference 4 (Rlzzo & Associates letter) and References 8 and 9 unless noted.
[1] Screen House Structure factors (SSI: f=127, Bu=27, Spectra: f=1.5, Br=28)
[2] Auxiliary/Turbine Building Structure factor (SSI: f=1.60, Bu=.27, Spectra: f=l.5, Br=.28)
[3] Containment Structure Factor (SSI: f=1.26, Bu=.15, Spectra f=1.8, Br=28)
[4] Containment Equipment Factor (SSI: f=2.09, Bu=.27, Spectra f=1.3, Br=28)
[5] RCS Primary Component. Factor (SSI: f=2.09, Bu=27, Spectra: f=19, Br=.28)
[6] Auxiliary Building Equipment Factor (SSI: f=1.30, Bu=.20, Spectra: [RHR Pump=I.3, RHR Hx=1.1, SWGR=1.4, CTS Pump=1.3, CTS Hx=1.2, RPS=1.3, Bu=.28 for all])
10
TABLE2 SEISMIC ACCELERATIONLEVELPROBABILITK'S (COOK SITE)
Event Tree Node Seismic Interval X
2a 2b 2c 2d 2e 3a 3b 3c Acceleration Range
- HedIan Accel.
(A )
- 0.275 0.325 0.375 0.425 0.475 0.525 0.575 0.675 0.25 - 0.30 0.30 - 0.35 0.35 - 0.40 0.40 - 0.45 0.45 - 0.50 0.50 - 0.55 0.55 - 0.60 0.60 - 0.75 Frequency of Exceedance 2.09E-05 1.23E-05 7.22E-06
'.25E-06 2.50E-06 1.47E-06 8.63E-07 5.08E-07
- 1.23E-05
- 7.22E-06
- 4.25E-06
- 2.50E-06
- 1.47E-06
- 8.63E-07
- 5.08E-07
- 1.03E-07 Frequency of Occurrence 8.6E-06 5.1E-06 2.97E-06 1.75E-06 1.03E-06 6.07E-07 3.56E-07 4.05E-07
- All accelerations units are g's.
~ FrequencIes are calculated on a per year bas1s 11
Table 3 Seismic Fragility Parameters Line Structure or Component Fragility Parameters 1
2 Screen House 3
4 - Reinforced Concrete Wal 5 - Piers 6 - Base Slabs 7 - Crane Runway Girders 8 - Colures/Buckling Failur 9 - Colums/Shear Failure 10 11 Auxiliary Building 12 13 - Soil Pressure 14 - Foundation Hat 15 - Steel Structure 16 - Concrete Structure 17 18 Turbine Pedestal 19 20 - Columns - Bent I. XII 21 - Columns - Bent II. XI 22 - Columns - Bent III. IV 23 IX, and X
24 - Columns - Bent V. VIII 25 - Colunas
- Bent VI. VII 26 27 Containment 28 29 - Containment Rebar 30 - Soil Pressure 31 32 Polar Crane 33 34 - Girder/Trunnion Weld 35 36 Ice Condenser 37 38 - Top Oeck Structure 39 - Ice Baskets 40 - Lower Support Structure 41 - Lattice Frame.
Cradles 42 and Columns 43 - Embehrnnts on Crane Wal 44 - Phasing Link 45 46 RCS Primary Components 47 48 - Reactor Vessel 49 - Lower Internals (Therma 50 Shield and Core Barrel) 51 - Upper Internals 52 - Control Rod Orive 53 mechanisms with RPI 54 - Reactor Coolant Pump 55 - Steam Generator 56 - Pressurizer and Support 57 0.32 0.16 0.31 0.3 O.l 0.42 0.27 0
0.35 0
0 0.27 0.3 0.29 0.31 0.31 0
0.27 0.29 0.27 0.3 0.3 0.3 0.27 0.27 0.27 0.12 0
0.3 0.27 0.31 0.42 0
0.27 0.15 0.3 0.34 0.3 0.48 0.32 0.48 0.27 0.27 0.27 0.27 0
0.27 0.13 0.27 0.42 0.32 0.32 0.27
- 0. 14 0.27 0
0 0
0.28 Beta r Beta u Beta 0.42 0.16 0.47 0.3 0.1 0.50 0.3 0.4 0.42 0.41 0.40 0.40 0.40 0.12 0.40 A).31
+ 0.50 0.15 0.40 0.43 0.40 0.55 0.32 0.55 0.13 0.27 0.50 0.32 0.32 0.27 0.31 1.27 1.05 1.06 1.33 1.4 1.48 1.36 0.98 0.85 0.91 1.22 1.3 1.27 0.82 1.2 1.53 0.99 0.39 1.41 1.8 1.39 2.48 1.21 2.37 2.1 1.17 2.24 2.3 1.62 2.84 0.84 12
Table 3 (Cont'd)
Seismic Fragility Parameters Line Structure or Component 58 Reactor Coolant Loop Pipi 59 60 Primary Component Supports 61 62 - Reactor Vessel 63 - Steam Generators 64 - Reactor Coolant Pumps 65 66 Pressurizer 67 68 - Safety Valves 69 - PORVs 70 71 Regenerative Heat Exchang 72 73 Excess Letdown Heat Excha 74 75 Level 5 Pressure Transmit 76 77 Auxiliary Piping Systems 78 (Secondary Side) 79 - Piping 80 - Supports
&1 82 ECCS Pmrys 83 84 - Residual Heat Removal 85 - Centrifugal Charging 86 - Safety Injection 87 - Boric Acid 88 89 ECCS Tanks 90 91 - Refueling Water Storage 92 - Accumulators 93 - Boron Injection 94 95 lPA Heat Exchangers 96 97 ECCS Valves 98 99 - Check Valves 100 - Nscellaneous Isolation 101 - HPSI Isolation Fragility Parameters Beta r Beta u Beta 0.14 0
0.14 Am 2.67 0.18 0.27 0.32 0
0.18 3.1 0
0.27 1.72 0
0.32 1.97 0.2 0.35 0.4 0.2 0.57 0.60 2.37 1.68 0.1 0.1 0.1 0
0.1 0.75 0
0.1 0.73 0
0.1 0.75 0.28 0.1 0.1 0.1 0.2 0.34 0.1 0
i0.1 0
+
0.1 0.83 0.94 0.94 0.94 0.31 0.19 0.25 0.21 0.37 0.45
=
0.49 0.45 0.51 0.95 0.9 1.42 0.3 0.2 0'6 0.76 0.2 0.26 0.1 0.35
~ 0.4 3.79
'0.6 0.65 2.36 0
0.1 2.25 0.23 0
0.23 2
0.31 0.28 0'2 0.81 13
Table 3 (Cont'd)
Seismic Fragility Parameters Line Structure or Curyonent Fragility Parameters Beta r Beta u Beta 102 103 Emergency Oiesel Generators 104 105 - Diesel Oil Purr@
106 - Fuel Oil Oay Tank 107 - Oiesel Generator 108 - SMiR (600V) 109 - Transformer 110 -
SWGR (4kV) 111 - Battery Rack 112 - Hotor Control Center 113 - Charger AB ~
CO.
N 114 - Control Panel 115 - AC Oistribution Panel 116 - Hiscellaneous Valves 117 - Batteries 118 - Cable Trays 119 120 Containment Spray 121 122 - Purps 123 - Spray Additive Tank 124 - Heat Exchangers 125 - Spray Additive Tank Vlv 126 - System Valves 127 128 Containment Recirc Fans 129 130 Auxiliary Feedwater 131 132 - Hotor Oriven Pump 133 - Turbine Oriven Perp 134 - Pump Isolation Valves 135 - SG Isolation Valves 136 - Fans (Room Cooling) 137 138 Reactor Protection System 139 140 - HCC 141 - Crid Inverter 142 - Hiscellaneous Panels 143 - Cable Trays 144 - Crid Transformer 145 - RPS/Aux Rack/STC 146 - Hain Control Board 147 148 Component Cooling Water 149 note - piping supports be 150 - Pumps (Piping Supports) 151 - Pumps (Water) 152 - Heat Exchanger 153 - Surge Tank 154 - Valves 155 0.25 0.34 0.25 0.3 0.28 0.31 0.27 0.3 0.31 0.2 0.25 0.37 0.37 0.45 0.4 0.36 0.38 0.48 0.3 0.45 0.58 0.88 0.88 0.65 0.3 0.39 2
0.66 0.91 1.2 0.79 1.77 0.21 0.21 0.71 0.64 1.52 5.9 0.34 0.31 0.48 0.48 0.26 0.21 0.34 0.3 0.49 0.74 0.74 0.6 0.21 0.19 5.11 2.15 0.71 1.98 0.2 0.35 0.2 0.6 0.6 0.28 0.2 0.3 0.26 0.26 0.34 0.4 0.36 0.65 0.65 0.96 1.46 0.4 2.48 2.36 0.31 0.27 0.41 0.91 0.27 0.27 0.34 0.6 0.31
'.21 0.21 0.31 0.26 0.27 0.34 0.34 0.46 0.65 0.41 2.28 2.28 3.9 4.37 1.09 0.74 0.35 0.66 0.19 0.3 0.2 0.74 0.48 0.26 0.48 0.34 0.28 0.28 0.48 3.32 7.61 3.4 1.98 2.22 0.79 5.11 0.88 0.44 0.82 0.39 0.41 0.34 0.88 0.51 2.28 1.07 1.3 2.15 0.01 0.34 0.36 0.4 0.65 0
0.21 0.28 0.2 0.26 0
0.27 0.23 0.35 0.6 ing reevaluated.
ignored for this analysis 14
Table 3 (Cont'd)
Seismic Fragility Parameters Line Structure or Component Fragility Parameters Beta r Beta u Beta Aa 156 Essential Service Water Sys 157 158 -
ESW Pumps 159 -
ESW Valves 160 -
ESW Strainers 161 162 Hain Steam System 163 164 - HSIVs 165 - PORVs 166 - HSIV Isol. Valves 167 - Safety Valves 168 - Steam Generator Dump 169 170 Hain Feedwater System 171 172 - Isolation Valves 173 - Control Valves 174 175 Switchyard 176 177 - Ceramic Insulators 0.31 0.25 0.40 1.13 0.26 0.6 0.65 2.15 0.22 0.32 0.39 2.01 0.1 0
0.1 1.88 0.1 0
0.1 1.75 0.1 0
0.1 3.5 0.2.
0.35 0.4 3.96 0.1 0
0.1 1.29 0.26 0.6 0.65 2.1 0.31 0.34 0.46 3.31 0.25 0.25 0.35 0.2 15
Line Structure or Component Table 4 Standard Oeviation from Fragility Hedian Standard Oeviation from Hedian za 2b 2c 2d 2e 3a 3b 3c 1
2 Screen House 3
4 - Reinforced Concrete Walls 5 - Piers 6 - Base Slabs'
- Crane Runway Girders 8 - Columns/Buckling Failure 9 - Columns/Shear Failure 10 11 Auxiliary Building 12 13 - Soil Pressure 14 - Foundation Hat 15 - Steel Structure 16 - Concrete Structure 17 18 Turbine Pedestal 19 20 - Columns - Bent I. XII 21 - Columns
- Bent II. XI 22 - Coloreds
- Bent III. IV 23 IX. and X
24 - Columns - Bent V, VIII 25 - Colons
- Bent VI. VII 26 27 Contai tvrznt 28 29 - Containment Rebar 30 - Soil Pressure 31 32 Polar Crane 33 34 - Girder/Trunnion Weld 35 36 Ice Condenser 37 38 - Top Oeck Structure 39 - Ice Baskets 40 - Lower Support Structure 41 - Lattice Frame.
Cradles 42 and Columns 43 - Embedments on Crane Wall 44 - Phasing Link 45 46 RCS Primary Components 47 48 - Reactor Vessel 49 - Lower Internals (Thermal 50 Shield and Core Barrel) 51 - Upper Internals 52 - Control Rod Orive 53 Mechanisms with RPI 54 - Reactor Coolant Pump 55 - Steam Generator 56 - Pressurizer and Supports 57 0.275
-3.654
-8.374
-2.886
-5.254
-16.275
-3.371 0.325
-3.255
-7.330
-2.529
-4.697
-14.604
-3.036 0.375
-2.913
-6.435
-2.222
-4.220
-13.173
-2.750 0.425
-2.615
-5.653
-1.955
-3.803
-11.921
-2.499 0.475
-2.349
-4.958
-1.717
-3.432
-10.809
-2.276 0.525
-2.110
-4.332
-1.503
-3.098
-9.808
-2.076 0.575
-1.893
-3.764
-1.308
-2.795
-8.899
, -1.894 0.675
-1.510
-2.761
-0.965
-2.261
-7.295
-1.572
-5.328
-4.771
-3.177
-2.759
-2.658
-2.265
-2.911
-2.505
-4.294
-2.402
-1.928
-2.156
-3.877
-2.089
-1.633
-1.852
-3.506
-1.811
-1.371
-1.581
-3.173
-2.870
-1.560
-1.333
-1.135 '0.921
-1.338
-1.117
-2.335
-0.932
-0.543
-0.727
-3.691
-3.849
-3.791
-3.277
-3.435
-3.377
-2.923
-3.080
-3.022
-2.613
-2.770
-2.712
-2.337
-2.495
-2.4~I
-2.089
-2.247
-2.189
-1.864
-2.021
-1.963
-1.467
-1.624
-1.566
-9.104
-3.650
-7.712
-3.236
-6.520
-2.882
-5.477
-4.550
-2.572
-2.296
-3.716
-2.048
-2.958
-1.823
-1.622
-1.426
-5.536
-2.565
-4.99i
-2.231
-4.536
-1.944
-4.132
-1.694
-3.773
-1.471
-3.450
-1.270
-3.157
-1.088
-2.640
-0.767
-2.329
-1.215
-0.261 0.573 1.314 1.982 2.588 3.657
-4.050
-4.327
-4.015
-3.993
-3.636
-3.943
-3.601
-3.690
-3.281
-3.613
-3.246
-3.430
-2.971
-3.325
-2.936
-3.203
-2.696
-3.068
-2.660
-3.001
-2.448
-2.838
-2.412
-2.819
-2.222
-2.628
-2.187
-2.654
-1.825
-2.259
-1.790
-2.363
-4.630
-3.911
-4.108
-3.608
-3.661
-3.270
-3.348
-3.121 l
-2.922
-2.609
-2.919
-2.737
-2.325 '1.824
-2.572
-2.281
-9.964
-2.631
-8'31
-2.037
-4.201
-6.637
-5.542
>>8.647
-3.602
-3.866
-6.115
-5.020
-8.029
-3.063
-3.580
-5.668
-4.573
-7.499
-2.602
~3.329
-5.277
-4.182
-7.035
-2.198
-3.106
-4.929
-3.834
-6.623
-1.839
-2.906
-4.616
-3.521
-6.252
-1.516
-2.724
-4.332
-3.237
-5.916
-1.223
-2.402
-3.831
-2.736
-5.322'0.705
-15.638
-14.353
-13.252
-12.289
-11.434
-10.664
-5.363
-4.744
-4.214
-3.751
-3.339
-2.968 16
Line Structure or Component 58 Reactor Coolant Loop Piping 59 60 Primary Component Supports 61 62 - Reactor Vessel 63 - Steam Generators 64 - Reactor Coolant Pumps 65
'66 Pressurizer 67 68 - Safety Valves 69 - PORVs 70 71 Regenerative Meat Exchanger 72 73 Excess Letdown Heat Exchanger 74 75 Level
& Pressure Transmitters 76 77 Auxiliary Piping Systems 78 (Secondary Side) 79 - Piping 80 - Supports 81 82 ECCS Pumps 83 84 - Residual Heat Removal 85 - Centrifugal Charging 86 - Safety Injection 87 - Boric Acid 88 89 ECCS Tanks 90 91 - Refueling Mater Storage 92 - Accmrulators 93 - Boron Infection 94 95 RHR Heat Exchangers 96 97 ECCS Valves 98 99,- Check Valves 100 - Hiscellaneous Isolation 101 - HPSI Isolation
-13.458
-12.530
-11.735
-11.039
-10.421
-6.790
-6.171
-5.641
-5.178
-4.766
-6.153
.-5.631
-5.184
-4.793
-4,.445
-9.865
-9.360
-8.469
-4.395
-4.058
-3.464
-4.132
-3.848
-3.347
-5.385
-4.967
-4.609
-2.996
--2.719
-2.483
-4.296
-2.275
-a.018
-2.091
-3.768
-1.926
-3.541
-3.140
-1.775
-1.509
-10.033
-9.763
-8.362
-8.092
-6.931
-5.680
'-4.568
-3.567
-2.657
-1.054
-6.661
-5.410
-4.297
-3.296
-2.387
-0.783
-10.033
-8.362
-6.931
-5.680
-4.568
-3.567
-2.657
-1.054
-8.627
-7.900
-7.278
-6.734
-6.250
-5.815
-5.420
-4.723
-2.586
-2.186
-1.844
-1.544
-1.278
-1.038
-0.820
-0.436
-3.210
-2.725
-2.309
-1.945
-1.622
-1.331
-12.291
-10.621
-9.190
-7.938
-6.826
-5.825
-12.291
-10.621
-9.190
-7.938
-6.826
-5.825
-12.291
-10.621
-9.190
-7.938
-6.826
-5.825
-1.067
-0.601
-4.915
-3.312
-4.915
-3.312
-4.915
-3.312
-3.311
-2.420
-3.219
-2.865
-2.483
-2.079
-1.787
-2.891
-2.611
-2.148
-1.531
-2.365
-1.851
-1.304
-2.147
-1.584
-1.100
-1.951
-1.341
-0.914
-1.773
-0.913
-0.587
-1.458
-2.819
-2.356
-1.959
-1.612
-1.304
-1.026
-0.774
-0.329
-6.558
-6.141
-5.783
-5.470
-5.192
-4.942
-4.714
-3.307
-3.050
-2.830
-2.637
-2.466
-2.312
-2.172
-21.019
-19.3a9
-17.918
-16.666
-15.554
-la.553
-13.643
-4.314
-1.926
-12.040 Table 4 (Cont'd)
Standard Oeviation from Fragility Hedian Standard Oeviation from Median 2a 2b 2c Zd 2e 3a 3b 3c
-16.236
-15.043
-14.021
-13.127
-12.332
-11.617
-10.968
-9.822 17
Table 4 (Cont'd)
Standard Deviation from Fragility Hedian Line Structure or Component Standard Deviation from Hedian 2a 2b 2c Zd 2e 3a 3b 3c 102 103 Emergency Diesel Generators 104 105 - Diesel Oil Pump 106 - Fuel Dil Day Tank 107 - Diesel Generator 108 -
SWGR (600V) 109 - Transformer 110 -
'12 - Hotor Control Center 113 - Charger AB. CD.
N 114 - Control Panel 115 - AC Distribution Panel 116 - Miscellaneous Valves.
117 - Batteries 118 - Cable Trays 119 120 Containment Spray 121 122 - Pumps 123 - Spray Additive Tank 124 - Heat Exchangers 125 - Spray Additive Tank Vlvs 126 - System Valves 127 128 Containment Recirc Fans 129 130 Auxiliary Feedwater 131 132 - Hotor Driven Pump 133 - Turbine Driven Pump 134 - Pump Isolation Valves 135 - SG Isolation Valves 136 - Fans (Room Cooling) 137 138 Reactor Protection System 139 140 - KC 141 - Crid Inverter 142 - Miscellaneous Panels 143 - Cable Trays 144 - Crid Transformer 145 - RPS/Aux Rack/STC 146 - Hain Control Board 147 148 Component Cooling Water 149 note - piping supports being 150 - Pumps (Piping Supports) 151 - Pumps (Water) 152 - Heat Exchanger 153 - Surge Tank 154 - Valves 155
-5.363
-1.931
-2.992
-4.086
-2.811
-3.857
-3.162
-1.863
-2.948
-3.484
-3.321
-3.164
-3.162
-5.062
-4.911
-1.562
'-2.574
-3.623
-2.366
-3.511
-2.605
-'1.494
-2.660
-3.294
-3.131
-2.907
-2.605
-4.633
-4.524
-1.247
-2.216
-3.226
-1.985
-3.215
-2.128
-1.179
-2.413
-3.132
-2.968
-2.687
-2.128
-4.266
-4.186
-0.971
-1.903
-2.879
-1.652
-2.956
-1.711
-0:903
'-2.'197
-2.989
-2.826
-2.494
-1.711
-3.946
-3.885
-0.725
-1.625
-2.570
-1.355
-2.725
-1.340
-0.658
-2.005
-2.863
-2.700
-2.323
-1.340
-3.660
-3.633
-4.174
-1.039
-3.383
-3.307
-2.919
-3.148
-3.756
-0.576
-3.126
-3.050
-2.511
-2.732
-3.398
-0.179
-2.906
-2.830
-2.162
-2.368
-3.085 0.168
-2.714
-2.637
-1.857
-2.045
-2.807 0.4.7
-2.543
-2.466
-1.586
-6.221
-6.221
-5.765
-4.255
-3.359 I
-S.i30
-5.730
-5.402
-3.998
-2.951
-5.309
-5.309
-5.091
-3.778
-2.602
-4.941
-4.941
-4.819
-3.585
-2.297
-4.614
-4.614
-4.577
-3.414
-2.026
-2.831
-7.546
-3.067
-5.062
-5.094
-3.067
-3.321
-2.641
-2.478
-7.167
-6.842
-2.863
-2.689
-4.633
-4.686
-2.581
-3.131
-4.266
-4.337
-2.165
-2.968
-2.336
-6.557
-2.536
-3.946
-4.032
-1.802
-2.826
-2.210
-6.304
-2.400
-3.660
-3.761
-1.478
-2.700
-6.221
-3.749
-3.883
-3.164
-5.730
-3.288
-3.466
-2.907
-5.309
-2.894
-3.108
-2.687
-4.941
-2.548
-2.795
-2.494
-4.614
-2.241
-2.517
-2.323 reevaluated.
ignored for this analysis
-61.764
-45.059
-30.748
-18.232
-7.110
-3.615
-0.505
-1.375
-2.293
-1.089
-2.518
-1.006
-0.437
-1.833
-2.749
-2.586
-2.169
-1.006
-3.404
-1.754
-2.557 0.754
-2.389
-2.312
-1.342
-4.319
-4.319
-4.359
-3.260
-1.782
-2.096
-6.077
-2.278
-3.404
-3.517
-1.188
-2.586 2.899
-4.319
-1.965
-2.267
-2.169
-3.369
-0.304
-1.148
-2.040
-0.846
-2.936 0.050
-0.747
-1.596
-0.419
-1.676
-2.646
-2.482
-2.029
-0.703
-3.170
-1.400
-2.464
-2.300
-1.782
-0.169
-'2.759
-1.490
-2.330 1.007
-2.249
-2.172
-1.120
-1.024
-1.929 1.451
-2.002
-1.926
-0.729
-4.052
-4.052
-4.162
-3.120
-1.560
-3.580
-3.580
-3.813
-2.874
-1.169
-1.992
-5.870
-2.167
-3.170
-3.295
-0.923
-2.482
-1.810
-5.506
-1.972
-2.759
-2.904
-0.457
-2.300 11.996
-4.052
-1.714
-2.039
-2.029 28.030
-3.580
-1.271
-1.639
-1.782
-2.329
-1.997
-0.703
-0,169
-0.236 '.117 18
Line Structure or Component 156 Essential Service Mater Sys 157 158 - ESM Pumps 159 - ESM Valves 160 -
ESW Strafners 161 162 Hain Steam System 163 164 - HSIVs 165 - PORVs 166 - HSIV Isol. Valves 167 - Safety Valves 168 - Steam Generator Dump 169 170 Hain Feedwater System 171 172 - Isolation Valves 173 - Control Valves 174 175 Switchyard 176 177 - Ceramic Insulators
-3.549
-3.129
-2.770
-2.455
-2.176
-1.925
-1.696
-1.294
-3.164
-2.907
-2.687
-2.494
-2.323
-2.169
-2.029
-1.782
-5.100
-4.672
-4.305
-3.984
-3.699
-3.442
-3.209
-2.798
-19.223
-18.506
-25.437
-6.668
-15.456
-17.552
-16.121
-14.869
-13.757
-12.756
-16.835
-15.404
-14.153
-13.041
-12.040
-23.767
-22.336
-21.084
-19.972
-18.971
-6.250
-5.893
-5.580
-5.302
-5.052
-13.786
-12.355
-11.103
-9.991
-8.990
-11.847
-10.243
-11.130
-9.527
-18.061
-16.458
-4.824
-4.423
-8.080
-6.477
-3.128
-2.871
-2.650
-2.458
-2.287
-2.133
-1.993
-1.746
-5.409
-5.045
-4.734
-4.462
-4.220
-4.003
-3.805
-3.457 0.910 1.387 1.796 2.154 2,4. s 2.757 3.017 3.475 Table 4 (Cont'd)
Standard Oevfatfon from Fragf1fty Hedfan Standard Deviation from Hedian 2a 2b Zc 2d 2e 3a 3b 3c 19
Line Structure or Component Table 5 Structure and Component Failure Probability for Each Seismic Interval Failure Probabilities 1
2 Screen House 3
4 - Reinforced Concrete Mails 5 - Piers 6 - Base Slabs 7 - Crane Runway Girders
=
8 - Coluws/Buckling Failure 9 - Columns/Shear Failure 10 11 Auxiliary Bui lding 12 13 - Soil Pressure 14 - Foundat1on Mat 15 - Steel Structure 16 - Concrete Structure 17
- 18. Turbine Pedestal 19 20 - Colures
- Bent I. XII 21 - Columns - Bent II. XI 22 - Columns - Bent III. IV 23 IX. and X
24 - Columns - Bent V. VIII 25 - Columns - Bent VI. VII 26 27 Conta1nment 28 29 - Containment Rebar 30 - Soil Pressure 31 32 Polar Crane
. 33 34 - G1rder/Trunnion Meld 35 36 Ice Condenser 37 38 - Top Oeck Structure 39 - Ice Baskets 40 - Lower Support Structure 41 - Lattice Frame.
Cradles 42 and Colutr~s 43 - Embedtrwnts on Crane Mall 44 - Phasing L1nk 45 46 RCS Primary Components 47 48 - Reactor Vessel 49 - Lower Internals (Then."al 50 Shield and Core Barrel) 51 - Upper Internals 52 - Control Rod Orive 53 Mechanisms w1th RPI 54 - Reactor Coolant hrcp 55 - Steam Generator 56 - Pressurizer and Supports 57 2a 2b 0.0000
- 0.0000 0.0022 0.0000 0.0000 0.0000 0.0000 0.0000 0.0062 0.0000 0.0000 0.0013 0.0000 0.0000 0.0000 0.0030 0.0040 0.0139 0.0019 0.0062 0.0000 O.acijo 0.0054 0.0139 0.0107 0.1151 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0011 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 2c 0.0019 0.0000 0.0139 0.0000 o.'aoao 0.0035 0.0000 0.0082 0.0287 0.0179 0.0019 0.0011 0.0013
'.0000 0.0022 0.0000 0.0287 0.4207 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0047 2d 2e 3a 3b 3c 0.0047 0.0107 0.0179 0.0359 0.0000 0.0000 0.0000 0.0000 0.0287 0.0446 0.0668 0.0968 0.0000 0.0000 0.0011 0.0030'.0000 0.0000 0.0000 0.0000 0.0071 0.0139 0.0227 0.0359 0.0668 0.0030 0.1841 0.0139 0.0000 0.0668 0.0000 0.0000 0.0000 0.0022 0.0107 0.0227 0.0359 0.0668 0.0968 0.1841 0.0548 0.0968 0.1357 0.1841 0;3085 0.0359 0.0668 0.0968 0.1357 0.2420 0.0000 0.0000 0.0000 0.0000 0.0047 0.0548 0.0808 0.1151 0.1587 0.2420 0.6915 0.9032 0.9713 0.9946 1.0000 0.0016 0.0040 0.0082 0.0139 0.0359 0.0000 0.0011 0.0026 0.0047 0.0139 0.0019 0.0040 0.0082 0.0179 0.0446 0.0000 0.0013 0.0026 0.0040 0.0094 0.0000 0.0019 0.0047 0.0107 0.0359 0.0010 0.0019 0.0035 0.0054 0.0139 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0016 0.0047 0.0227 0.0000 0.0010 0.0019 0.0035 0.0082 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0035 0.0000 0.0000 0.0000 0.0000 0.0000 0.0179 0.0359 0.0668 0.1151 0.2420 0.0047 0.0107 0.0227 0.0359 0;0808 0.0030 0.00.".
0.0139 0.0227 0.0548 0.0035 0.0082 0.0179 0.0287 0.0668 0.0000 0.0000 0.0000 0.0016 0.0548 0.0054 0.0139 0.0227 0.0359
,0.0808 20
Line Structure or Component 58 Reactor Coolant Loop Piping 59 60 Primary Component Supports 61 62 - Reactor Vessel 63 - Steam Generators 64 - Reactor Coolant Pumps 65 66 Pressurizer 67 68 - Safety Valves 69 - PORVs 70 71 Regenerative Heat Exchanger 72 73 Excess Letdawn Heat Exchanger 74 75 Level 8 Pressure Transmitters 76 77 Auxiliary Piping Systems 78 (Secondary Side) 79 - Piping 80 - Supports 81 82 ECCS Pumps 83 84 - Residual Heat Removal 85 - Centrifugal Charging 86 - Safety Infection 87 - 8oric Acid 88 89 ECCS Tanks 90 91 - Refueling Water Storage 92 - Accumulators 93 - Horon I+ection 94 95 M Heat Exchangers 96 97 ECCS Valves 98 99 - Check Valves 100 - Hiscellaneous Isolation 101 - HPSI Isolation Table 5 (Cont'd)
Structure and Corponent Failure Probability for Each Seismic Failure Probabilities 2a 2b 2c 2d o.oooo o.oooo o.aooo o.oooo Interval 2e 3a 3b 3c 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 o.'Oooo o.oaoo o.oooo
o.oooo o'.oooo o'.oooo o'.oooo o.aoao 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
'0.0000 0.0000 0.0000 0.0000 0.0000 0.0016 0.0035 0.0071 0.0139 0.0000 0.0000 0.0000 0.0000 0.0000 0.0227 0.0000 0.0000 0.0000 0.0010 0.0287 0.0446 0.0668 0.0000 0.0040 0.1587 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0094 0.2420 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0040 0.1587 0.0000 0.0000 0.0000 0.0000 O.OOCO 0.0000 0.0000
. 0.0000 0.0054 0.0179 0.0359 0.0668 0.1151 0.1587 0.2119 0.3446 0.0000 0.0035 0.0107 0.0287 0.0548 0.0968 0.1587 0.2742 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.000('.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 O.OCII)0 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0022 0.0071 0.0082 0.0227 0.0446 0.0000 0.0022 0.0047 0.0026 0.0094 0.0287 0.0179 0.0668 0.0094 0.0548 0.0359 0.0668 0.0968 0.1841 0.0968 0.1587 0.1841 0.3085 0.0179 0.0287 0.0446 0.0808 0.0968 0.1587 0.2420 0.3821 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0011 0.0026 0.0047 0.0071 0.0107 0.0179 0.0287 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 21
Table 5 (Cont'd)
Structure and Cotryonent Failure Probability for Each Seismic Interval Line Structure or Component Failure Probabilities 2a 2b 2c 2d 2e 3a 3b 3c 102 103 Emergency Diesel Generators 104 105 - Diesel Oil Putrp 106 - Fuel Oil Oay Tank 107 - Oiesel Generator 108 - SNGR (600V) 109 - Transformer 110 - SNGR (4kV) 111 - Battery Rack 112 - Motor Control Center 113 - Charger AB. CO. II 114 - Control Panel 115 - AC Oistribution Panel 116 - Miscellaneous Valves 117 - Batteries 118 - Cable Trays 119'20 Containment Spray 121 122 - Pumps 123 - Spray Additive Tank 124 - Heat Exchangers 125 - Spray Additive Tank Vlvs 126 - System Valves 127 128 Containment Recirc Fans 129 130 Auxiliary Feedwater 131 132 - Motor Driven Pump 133 - Turbine Oriven Pump 134 - Pump Isolation Valves 135 - SG Isolation Valves 136 - Fans (Room Cooling) 137 138 Reactor Protection System 139 140 - MCC 141 - Crid Inverter 142 - Miscellaneous Panels 143 - Cable Trays 144 - Crid Transfonrar 145 - RPS/Aux Rack/STC 146 - Main Control Board 147 148 Cor:onent Cooling Water 149 note
- piping supports being 150 - Pumps (Piping Supports) 151 - Pumps (Water) 152 - Heat Exchanger 153 - Surge Tank 154 - Valves 155 0.0000 0.0287 0.0016 0.0000 0.0026 0.0000 0.0000 0.0668 0.1151 0.0054 0.0139 0.0000 0.0287 0.0000 0.0094 0.0000
,0.0000 0.0000
'0.0047 0.0000 0.0179 0.0359 0.0019 0.0000 0.0000 0.0000 0.0000 0.0000 0.0808 0.0040 0.0000 0.0010 0.0019 0.0047 0.0000 0.1357 0.0082 0.0010 0.0016 0.0040 0.0179 0.0000 0.0000 0.1841 0.0287 0.0022 0.0548 0.0016 0.0446 0.1841 0.0179 0.0016 0.0026 0.0071 0.0446 0.0000 0.0000 0.2420 0.0548 0.0054 0.0968 0.0035 0.0968 0.2742 0.0227 0.0022 O'.004O 0.0107 0.0968 0.0000 0.0000 0.0000 0.1587 0.0000 0.0000 0.0019 0.0010 0.0000 0.3085 0.0010 0.0011 0.0062 0.0035 0.0000 0.4602 0.0019 0.0026 0.0179 0.0094 0.0011 0.5398 0.0035 0.0047 0.0359 0.02"7'.0026 0.6554 0.0062 0.0071 0.0668 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0016 0.0000 0.0000 0.0000 0.0000 0.0047 0.0000 0.0000 0.0000 0.0000 0.0139 0.0000 0.0000 0.0000 0.0000 0.0227 0.0026 0.0000 0.0011 0.0000 0.0000 0.0011 0.0000 0.0047 0.0000 0.0022 0.0000 0.0000 0.0054 0.0010 0.0071 0.0000 0.0040 0.0000 0.0000 0.0179 0.0016 0.0107 0.0000 0.0062 0.0000 0.0000 0.0359 0.0026 0.0139 0.0000 0.0082 0.0000 0.0000 0.0808 0.0040 0.0000 0.0000 0.0000 0.0000 0.0019 0.0000 0.0000 0.0022 0.0010 0.0040 0.0000 0.0000 0.0062 0.0030 0.0071 0.0000 0.0000 0.0139 0.0062 0.0107 reevaluated.
ignored for this analysis 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.3085 0.0968 0.0139 0.1587 0.0062 0.1587 0.3446 0.0359 0.0035 0.0054 0.0179 0.1587 0.0000 0.0446 0.0054 0.7580 0.0094 0.0107 0.0968 0.0000 0.0000 0.0000 0.0000 0.0446 0.0227 0.0000 0.0139 0.0000 0.0000 0.1357 0.0054 0.9978 0.0000 0.0287 0.0139 0.0179 0.0000 0.3821 0.1357 0.0227 0.2119 0.0107-0.2420 0.4207 0.0548 0.0047 0.0071 0.0227 0.2420 0.0000 0.0808 0.0107 0.8413 0.0139 0.0179 0.1357 0.0000 0.0000 0.0000 0.0010 0.0668 0.0287 0.0000 0.0179 0.0000 0.0000 0.1841 0.0071 1.0000 0.0000 0.0446 0.0227 0.0227 0.0019 0.5000 0.2420 0.0668 0.3446 0.0287 0.4602 0.5398 0.0968 0.0071 0.0107 0.0446 0.4602 0 '030 0.1587 0.0287 0.9192 0.0227 0.0287 0.2420 0.0000 0.0000 0.0000 0.0022 0.1357 0.0359 0.0000 0.0287 0.0030 0.0019 0.3446 0.0107 1.0000 0.0000 0.1151 0.0548 0.0446 22
Line Table 5 (Cont'd)
Structure and Component Failure Probability for Each Seismic Interval l
Structure or Component
.Failure Probabilities 2a 2b Zc 2d 2e 3a 3b 3c 156 Essential Service Mater Sys 157 158 - ESM Pumps 159 - ESM Valves 160 - ESM Strainers 161 162 Hain Steam System 163 164 - HSIVs 165 - PORVs 166 - HSIV Isol. Valves 167 - Safety Valves 168 - Steam Generator Dump 169 170 Hain Feedwater System 171 172 - Isolation Valves 173 - Control Valves 174 175 Switchyard 176 177 - Ceramic Insulators 0.0000 0.0010 0.0030 0.0071 0.0179 0.0287 0.0548 0;1151 0.0000 0.0019 0.0040 0.0071 0.0107 0.0179 0.0227 0.0446 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0030 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.8159 0.9032 0.9554 0.9821 0.9929
'0.9970 0.9987 1.0000 0.0010 0.0022 0.0040 0.0071 0.0139 0.009 0.0287 0.0446 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 LOCA initiators from Notebook Fig. 3
- small break 0.007 0.02 0.03 0.05 0.08 0.12 0.15 0.2
- medium break 0.0002 0.001 0.002 0.004 0.008 0.013 0.015 0.03 23
Ion Oevlat 0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2
2.1 2.2 2.3 2.35 2.4 2.45 2.5 2.55 2.6 2.65 2.7 2.75 2.8 2.85 2.9 2.95 3
3.05 3 '
3.15
. 100 Table 6 Normal Error Lookup Table Area 0
0.0398 0.0793 0.1179 0.1554 0.1915 0.2258
'.258 0.2881 0.3159 0.3413 0.3643 0.3849 0.4032 0.4192 0.4332 0.4452 0.4554 0.4641 0.4713 0.4773 0.4821 0.4861 0.4893 0.4906 0.4918 0.4929 0.4938 0.4946 0.4953 O.496 0.4965 0.497 O.4974 O.4978 O'.4981 0.4984 O'.4987 0.4989 0.499 0.5 0.5 Extracted from Reference 16 24
Basic Event Uses Lines Table 7
Basic Event Seismic Failure Rates Seismic Subinterval S-AC-ACC-FA S-ACDP-120VAC-FA 5-ACDP-1AB/CO-FA S AUX-BLDG-FA S-8-250VOC-FA S-BR-250VDC-FA 5-BC-250VOC-FA S-CT-120VAC-FA 5-CH-HP I-FA S-CP-IAB/CO-FA S-CT-11-FA 5-CT-Tl1-FA S-CT-250VOC-FA S-CV-ACC-FA S-CV-HPI-FA S-CV-RHR-FA 5-OG-lAB/CO-FA S-DOP-1AB/CO-FA S-FOOT-1AB/CO-FA S-HE-CCM-FA S-HE-CTS-FA S-HE-RHR-FA 5-IC-MEDHEN-FA S-IC-ICE-BASB-FA S-IC-LF-O'-CO-FA S-IC-LS-STRUT-FA S-IC-PHAS-LNK-FA S-IC-TOP-DECK-FA S-IIIV-HSl-FA S-HC-11-FA S-NC-IZOVAC-FA, S-HC-250VOC-FA S-HC-IAB/CO-FA S-HSIV-HS1-FA S-HV-RHR-FA S-OT-11-FA S-OT-120VAC-FA S-OT-T11-FA S-P IV-AFW-FA S-PH-AFW-FA S-PH-CCW-FA S-PH-CTS-FA S-PH-RHR-FA S-PT-ESW-FA S-TK-RMST-FA S-SGIV-APA-FA S-S I-HP I-FA S-SV-HS1-FA 5-SMGR-Il-FA S-SWGR-Tll-FA S-TK-CCW-FA S-TRB-PED-FA S-V-1AB/CO-FA 5-V-CCM-FA 13-16 38-45 92 115 0
111 111 113 118 85 114 118 118 118 99 99 99 105 105 106 152 124 96 0
0 0
0 0
0 0
0 115 0
164 100 109 20-25 122 84 158 91 135 86 167 108 110 153 154 154 142+145 0
134 132 150+151 2b 0.0227 0.0010 0.0000 0.0230 0.0047 0.0047 0.0040 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 2a 0.0082 0.0000 0.0000 0.0059 0.0000 0.0000 0.0019 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
- 0. 1587 0.0026 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.3085 0.0094 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0010 0.0000 0.0000 0.0000
, 0.0011 0.0026 0.0094 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 o.'aoao O.OQ00 0.0000 o.oaao 0.0000 0.0000 0.0000 0.0000 0.0000 0.0010 0.0035 0.0010 0.0022 0.0000 0;0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0019 0.0019 0.0000
, 0.0000 0.0287 0.0668 0.0000 0.0000 2c 0.0446 0.0016 0.0000 0.0539 0.0179 0.0179 0.0082 0.0000 0.0000 0.0010 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.1151 0.0022 0.4602 0.0287 0.0000 0.0000 0.0000 0.0000
" 0.0000 0.0000 c 0000
'.0000 0.0000 0.0016 0.0000 0.0000 0.0026 0.0287 0.0000 0.0000 0.0000 0.0000 0.0000 0.0035 0.0107 0.0030 0.0071 0.0000 0.0000 0.0000 o.aooo 0.0000 0.0010 0.0065 0.0040 o.ao4o Zd 2e 0.0668 0.0968 0.0026 0.0000 0.1094 0.0446 0.0040 o.'aooo 0.1874 0.0968 O.O446 O.O968 0.0179 0.0227 0.0000 0.0000 0.0000 0.0016 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.1841 0.0000 0.0022 0.0000 0.0000 0.0000 0.0000 o.'oooa 0.0000 0.0000 0.0000 0.2420 0.00<5 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0026 o.oaao 0.0000 0.0047 0.0548 0.0000 0.0000 0.0000 0.0000 0.0000 0.0094 0.0287 0.0071 0.0179 0.0000 0.0000 0.0000 0.0022 0.0016 0.0030 0.0165 0.0071 0.0071 0.0141 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0040 0.0000 0.0000 0.0071 0.0968 0.0000 0.0000 0.0000 0.0000 0.0000 0.0227 0.0548 0.0179 0.0359 0.0000 0.0000 0.0000 0.0054 0.0035 0.0062 0.0393 0.0107 0.0107 0.0062 0.0139 0.5398 0.6554 0.0548
. 0.0968 0.0000 0.0000 3a 0.1587 0.0054 0.0000 0.2715 0.1587 0.1587 0.0359 0.0000 0.0000 0.0035 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.3085 0.0287 0.7580 0.1587 0.0000 0.0294 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0054 0.0000 0.0000 0.0107 0.1587 0.0000 0.0000 0.0000 0.0000 0.9978 0.0446 0.0968 0.0287 0.0668 0.0000 0.0000 0.0000 0.0139 0.0062 0.0139 0.0750 0.0179 0.0179 3b 0.1841 0.0071 0.0000 0.3645 0.2420 0.2420 0.0548 0.0000 0.0000 0.0047 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.3821 0.0446 0.8413 0.2420 0.0000 0.0554 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0071 0.0000 0.0000 0.0179 0.2119 0.0000 0.0000 0.0000 0.0000 1.0000 0.0808.
0.1587 0.0548 O.'O968 0.0010 0.0000 0.0000 0.0227 0.0107 0.0227 0.1191 0.0227 0.0227 3c 0.3085 0.0107 0.0000 0.5769 0.4602 0.4602 0.0968 0.0030 0.0000 0.0071 0.0030 0.0030 0.0030 0.0000 0.0000 0.0000 0.0019 0.0019 0.5000 0.1151, 0.9192 0.3821 0.0000 0.1456 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0107 0.0000 0.0000 0.0287 0.3446 0.0019 0.0000 0.0000 0.0000 1.0000*
0.1587-0.2742 0.1151 0.1841 0.0022 0.0000 0.0000 0.0668 0.0287 0.0548 0.2956 0.0446 0.0446 Piping supports are being reevaluated.
this is ignored for this analysis.
Note that this failure is not included in the quanitification results.
25
Basic Event Uses Lines Table 7 (Cont'd)
Basic Event Seismic Failure Rates Seismic Subinterval 5-V-CTS-FA S-V-ESM-FA S-V-HP I-FA S-V-RHR-FA 5-TK-BIT-FA 5-HC-Tll-FA S-PT-AFM-FA 5-MISC-PN-FA 5-CEQ-FA 5-ST-ESM-FA 126 159 101+102 100 93 0
132+136 128
...160 2a Zb 2c 2d 0.0000 0.0011 0.0026 0.0047 0.0000 0;0019 0.0040 0.0071 0.0000 0.0011 0.0026 0.0047 0.0000 0.0011 0.0026 0.0047 0.0000 0.0022
. 0.0047 0.0094 0.0000 0.0000 0.0000 0.0000 0.0000 0.0016 0.0047 0.0139 0.0048 0.0132 0.0303
- 0.0546 0.0019 0.0062 0.0179 0.0359 0.0000 0.0000 0.0000 0.0000 2e 0.0071 0.0107 0.0071 0.0071 0.0179 0.0000 0.0227 0.1046 0.0668
- 0.0000 0.0107 0.0179 0.0107 0.0107 0.0287 0.0000 0.0446 0.1716 0.0968, 0.0000.
3b 3c 0.0179 0.0287 0.0227 0.0446 0.0179 0.0287 0.0179 0.0287 0.0446 0.0808 0.0000 0.0000 0.0668 0.1357 0.2272 0.3946 0.1357 0.2420
'.0000 0.0030 26
Tree Node Event Tree Nodes Uses Lines 2a Table 8 Event Tree Node Sexism)c Failure Rates Seismic Subknterval Zb 2c 2d 2e 3a 3b 3c CSF PVP RCF HPB SPB SHF SSP OSP ROO 29.30.55.63 0.0054 48.58.62 0.0000 56.64 0.0000 181 0.0002 54+180 0.0070 4-9 0.0022 79.80 0.0054 177 0.8159 49.51.52 0.0000 0.0139 0.0287 0.0548 0.0808 0.0000 0.0000 0.0000 0.0000 0.0011 0.0047 0.0179 0.0359 0.0010 0.0020 0.0040 0.0080 0.0200 0.0300 0.0500 0.0800 0.0075 0.0192 0.0401 0.0680 0.0179 0.0359 0.0668 0.1151 0.9032 0.9554 0.9821 0.9929 0.0000 0.0000 0.0000 0.0010 0.1151 0.1587 0.2467 0.0000 0.0000 0.0000 0.0668 0.1151 0.2420 0.0130 0.0150 0.0300 0.1200 0.1500 0.2035 0.1054 0.1635 0.3063 0.1587 0.2119 0.3446 0.9970 0.9987 1.0000 0.0035 0.0082 0.0307 27
Table 9 Event Transient w/o power conversion Small LOCA Loss of Station Power Small LOCAf Large LOAN Steamline Breaks Loss of Essential Service Waterg Direct Damage 2a 1.61E-6 6.87E-6 3.73E-B 1.52E-S 4.64E-B Seismically Induced Initiating Event Frequencies by Seismic Subinterval Seismic Subinterval 2b 2c Zd 4.79E-7 1.31E-7 2.75E-B 2e 3a 3b 3c 1.00E-B 4.31E-6 9.03E-B 7.86E-S 3.32E-B 2.50E-6 8.17E-B 1.2BE-S 9.30E-SX 5.07E-B 1.35E-6 7.93E-B 2.90E-S 9.66E-B 6.04E-B 6.82E-7 7.19E-B 3.3BE-B 8.86E-B 5.62E-B 3.26E-7 5.90E-B 3.58E-B 6.16E-B 4.54E-S 1.45E-7 3.88E-B 3.44E-B 3.90E-B 3.60E-S 7.86E-B 4.43E-B 7.3SE-S 4.14E-B 5.29E-B 7.09E-B 8.52E-B 9.59E-B 8.32E-B 6.98E-B 5.66E-B 1.00E-7 g - Event without offsite power Only frequencies greater than 1.E-B are listed.
28
Table 10 Seismic Core Damage Frequencies Event Transient w/o power conversion Small LOCA Loss of Station Power Large LOCAL Small LOCAf Steamline Breaks Loss of Essential Service Waterf Direct Damage Seismic Subinterval 2a 2b 2c 2.32E-B 2.77E-S 2.08E-S 4.64E-B 7.09E-B 8.52E-B 1.00E-7 2.43E-7 3.68E-7 1.69E-B 1.94E-B 2d 2e 4.25E-7 2.92E-B 3.57E-B 1.38E-B 3.15E-7 1.43E-B 3.33E-B 4.12E-B 2.07E-B 9.59E-B 8.32E-B 3a 2.10E-7 1.86E-B 3.55E-S 3.74E-B 2.53E-B 3b 1.15E-7 2.20E-B 2.82E-B 2.83E-B 2.57E-B 3c 7.62E-B 5.95E-B 3.98E-B
, 4.76E-B 5.04E-B 7.OE-B small 1.85E-6 1.14E-7 1.83E-'7 2.10E-7 1.35E-7.
6.98E-B 5.66E-B 1.00E-7 6.08E-7 Total Conditional 1.70E-7 3.42E-7 5.10E-7 0.020 0.067 0.172 6.00E-7 5.08E-7 3.97E-7 Q.M3 0.493 0.654 2.75E-7 e
0.772 3.74E-7 '.17E-6 0.923 f - Event without offsite power Only frequencies greater than 1.E-B are listed.
Seismic Fa1lures Dominating the Initiating Events Transient w/o power conversion Loss of Station Power Large LS'A Small LOCAL Steamline Breaks Loss of Essential Service Water D1rect Damage Seismic Event Alone Ceramic Insulators Pressurizer supports Pipe Break Secondary Piping/ supports Screenhouse Failure Containment Fa1lure - So11 Pressure 29
Table 11 Basic Events Contribution to Seismic Core Damage Frequency Interval Normal all LOSP 2a-2d 2e 3a 3b Total S-AUX-BLDG-FA S-OT-11-FA 5-FOOT-1AB/CO-FA ONPT-----PP4PS.
S-BC-250VDC-FA S-MISC-PAN-FA A-CB-11AC-BDCC S-8-250VDC-FA S-BR-250VDC-FA S-IC-ICE-BASB-FA 3.08E-B 1.40E-B 6.54E-9 1.64E-B 4.69E-07 2.25E-07 2.23E-07 1.32E-07 7.53E-OB 3.08E-OB 1.53E-OB
- 1. 17E-7 5.24E-B 3.36E-B 7.66E-B 3.46E-B 2.86E-B 8.63E-9 4.35E-9 3.94E-B 2.20E-B 3.94E-B 2.20E;8 2.53E-B 1.67E-B 2.47E-B 2.20E-B 7.75E-B 2.83E-B 1.75E-9 2.59E-9 9.61E-9 2.05E-9 9.61E-9
.2.05E-9 2.ooE-9 7.41E-7 3.50E-7 3.38E-7 1.32E-7 9.90E-B 4.72E-B 1.53E-B 7.30E-B 7.30E-B n/a Key S-AUX-BLDG-FA S-FOOT-lAB/CO-FA S-OT-11-FA S-8-250VDC-FA 5-BR-250VOC-FA DNPT-----PP4PS S-BC-250VOC-FA S-MISC-PAN-FA S-IC-ICE-BASB-FA Auxiliary Building Fuel Dil Oay Tank (block wall)
Transformer (block wall)
Battery Rack Battery Rack TOAFP random failure Battery Charger MCC and RPS Racks Misc Ice Condenser 30
.S Conditional Probability of Occurrence 1.0E+00 1.QE-01
~ yO
~0
~
~
~1
~
~
~t
~ yO
~ 0
~ 0
~ 0 1.0E-02 1.0E-03 1.0E" 04 8LOCA MLOCA 1.0E-05 1.0E-06 1.0E" 07 0.0 0.2
.~.0.4 5 0.6 '.8.
1.0 1.2 1.4 Peak Ground Acceleration (g's)
Eigure l
Seismica11y Induced Small and Medium LOCA Probabi1ities
APPENDIX A WESTINGHOUSE FRAGILITYANALYSIS Westinghouse Letters
- 1) AEP-94-760, "Fragility Parameter Review" (8/16/94)
- 2) AEP-94-785 "Transmittal of Fragility Data (9/23/94) and P
- 3) AEP-94-789 "Supplementary Seismic Fragility Estimates" (10/3/94).
Westinghause Electric Carparatian Energy Systems Box 355 Pinsburg Pennsylvania 15230 0355 Mr. R. Bennett Nuclear Safety Section American Electric Power Service Corporatioa One Riverside Plaza Columbus, OH 43216M31 August 19, 1994 AEP-94-760 NTD-NSRLAPL-94-214 AMERICANELECTRIC POWER SERVICE CORPORATION DONALD,C. COOK UNITS 1 AND 2 ili P
ete Review Ref.:
1.
2.
3.
AEP-94-746 "Seismic Fragility Assessment, Donald C. Cook Nuclear Plants," Rev. 1, March 1993.
"Seismic Fragilities of Civil Structures and Equipment Components at the Diablo Canyon Power Plant," NTS Engineering, Report No. 1643.02, Sept. 1988.
Dear Mr. Bennett:
~
~
Fra ili data has g
ty been regenerated for four components following the approach used by Diablo Canyon+ in response to a request by AEPSC, as described in Reference
- 1. This information is required for the effort to demoastrate that the coaservative fragilityparameters given in Reference 2 have not masked any dominant contributors or effected ranking for the Donald C. Cook seismic IPEEE PRA evaluation.
No significant difference has beea found between the regenerated HCLPF values and those previously reported.
HCLPF refers to High Confidence of Low Probability of Failure values.
The four components reviewed are:
l.
2.
3.
Masoary wall around EDG Diesel Fuel Day Taak 4 KVswitchgear anchorage CCW HX supports including cracks identified during the A46 walkdown AuxiliaryBuilding
Comparison of the fragilitydata are as follows, (old data from Ref. 2):
COMPONENT REVISED VALUES HCLPF A
OLD VALUES Pr Pu HCLPF A
Pr Masonry Wall 0.26g 0.95g 0.28 0.27 0.25g 0.27g 0.05 0.00 4 KV Switchgcar Anchorage 0.58g 1.77g 0.31 0.37 0.55g 0.66g 0.10 0.00 CCW HX Supports 0.46g 1.07g 0.28 0.23 0.45g 0.54g 0.10 0.00 AuxiliaryBuilding 0.32g 0.85g 0.31 0.29 0.30g 0.38g 0.13 0.00 The followingsheets provide a detailed summary of the fragilityparameters.
Note that the references for the attached summary are different than those listed on the first page of this letter. A list of summary references is attached at the end of the summary.
Also included is a copy of the Rizzo Associates letter on spectral fragilitydata used in this reevaluation, and referenced in the attached summary.
In addition, a copy of the Diablo Canyon seismic fragilities report is included.
Ifyou have any questions or comments, please call Robin Lapides (412/374-5683) or me.
Very truly yours, RSL/bbp Keith F. Matthews Senior Sales Engineer Power Systems Field Sales CC:
J. Kingseed D. Malin V. VanderBurg R. Lapides
- AEPSC
- AEPSC
- AEPSC
-W E. Lewis
- AEPSC T. Georgantis
- AEPSC J. McNanie
- AEPSC M. Wilken
- AEPSC
ATTACHMENT1 AEP-94-760 NTD-NSRLA-OPL-94-214 AEPSC74$ NSRLA194
D.C. COOK EQUIPMENT FRAGILITY 4KV SWITCHGEAR FRAGILI'IYESTQd'ATE MSE-WSIA12(94)
A: noted in Sectioa 4.49 of Reference 1, the 4KV switchgear is mounted on the 609'evel of the AEP Auxili'tryBuilding. The equipment assembly has a frequency between 5 and 10 Hz.
The applicable spectral acceleration at 5Hz and 5% damping for the 609'evel is 0.42g with a floor ZPA of 0.22g.
The corre'sponding free field ZPA acceleration is 0.2g.
The analysis tabulated below defines the spectral HCLPF value at the mounting location of the switchgear.
Now the HCLPF values reported in Reference 1 correspond to the plant free field ZPA values.
Since the fioor level is above the AuxiliaryBuilding base, the HCLPF value must be lowered: the spectral values must be scaled to represent the free field ZPA value.
This factor is developed in two stages: first the spectral value is scaled to be representative of the floor ZPA; and second, the fioor ZPA is scaled to be representative of the free field acceleration.
This factor is given for the switchgear mounting as (0.22/0.42) (0.2/0.22), and is equal to 0.48.
This factor is deterministic since two other parameters,spectial effects aad modeling effects, already take iato account the variability of the earthquake and building dynamic characteristics.
MATIHtIAL DVCTIL'ITY MODELING F
median 1.4 1.09 1.77 1.0 028 0.14 0
0.12 0.11 047 028 0.12 0.18 007 0.20 Refer encel(NOTES)
AEP450 &RiZZO(4)
Ref. 4, (1)
WELD Duc (2)
RIZZO (4)
Resuitant 381 031 097 0.47 median vaiues Values above are applicable to switchgear at the 609'evel The floor median spectral acceleration capacity = seismic design capacity (Ref. 2) times median margin factor = 1.05~3.51 = 3.69g The HCLPF floor value is HCLPF(floor) = 3.69~e(-1.65~(0.31+
0.37) = 1.20g The free field mediaa spectral acceleration capacity
= 3.69 ~ 0.48 = 1.77g For free field,'he HCLPF value is HCLPF(free field) = 0.48~ HCLPF(fioor) = 0.48~1.20 = 0.58g
D.C. COOK EQUIPMENT FRAGILITY 4KV SWITCHGEAR PRAGIIZTYES'I%MATE NOTES MSE-WSIAI2(94)
The yield strengths of steel materials vary randomly; Table 1 (Steel Yield Strength Characteristics) of Reference 4 shows the mean and coefficient of variability (COV) for various steels.
The COV is defined as the ratio of the standard deviation divided by the mean value.
After reviewing the data on Table 1 of Reference 4 it was determined that reasonable values for these parameters, mean and standard deviation, are 1.1 and 0.11 respectively The material is defined in terms of the mean value and has been converted to median value using a relationship described in Equation 2.4 of Reference I.
2.
F'= 1.l*e(-0.11'/2) = 1.09 Sheets 393 through 395 of Appendix C of Reference 5 describe the mounting details used on this equipment.
The corners of the cabinet are plug welded to shim plates
. which are filletwelded together and to the floor. Because of the joint conditions, it is felt that gross deformability of the connection is limited. Por the purpme of this evaluation, it is assumed that the connection median ductility is 2.0. Prom the data reported in Section 4.49 of Reference 1, it is clear that the equipment is flexible and damping has an effect on the response; a value of 5% is considered to be zeasonable.
TABLE5-1 of Reference 3 is used to define the ductility margin factors used in the fragility analysis.
'he variability in modeling lies primarily in the ability of the analytical model to estimate system frequencies. For this evaluation the median factor is taken equal to 1 since the models are adequate.,
This evaluation follows the approach set forth in Reference 3 and is used to define variability. In this approach equation 4-33 of Refererice 3 is used to estimate P; the value for modeling can be calculated as follows:
P= la(spectral acceler. at 85% exceedence probability frequency/spectra acceleration at median frequency).
The estimated median frequency was taken as 5 Hz; the system frequency has been defined. in Section 4.49 of Reference 1.
The 85% exceedence frequency has been calculated following the suggestion given on page 4-52 of Reference 3. 'Ihe 85%
exceedence frequency, f> is given by 5 e~" =
3.9H Using the floor response given in Reference 2 and 5% damping, we have f = 5HZ RRS = 0.42g fp = 3.9Hz RRS = 0.55g and P= In(0.55/0.42) = 0.27 4.
The P values used were provided by RIZZO Associates, Reference 9 D.C. COOK EQUIPMEN'I'RAGIIZIY MSE-WSL-012(94)
FRAGILI'IYESTIMATE FOR TKE AMQLI'ARYBUILDING
~ I
"~
A review of the calculations given in Reference 6 indicates that the steel columns supporting the crane girders in the auxiliary Building control the fragilityvalue and were designed on the basis of the actual material strengths zepozted in the millceztifications, ie, the measured yield strengths of the A-36 steel used, varied between 36 ksi and 50 ksi. According to the calculation, Reference 6, a concrete wall is attached to one of the column fianges which supplies some lateral resistance to weak axis bending of the crane girder columns.
This report also indicates that under seismic design conditions some of the peak calculated steel stresses exceed 80% of the design anowable stress.
For this reason, it was concluded that the critical members used in the design of the AuxiliaryBuilding would be the steel columns supporting the crane zails.
Because the steel yield strengths used were millcertified, there is only minimal reserve material stzength reserve above that used in the design.
The median margin factor for the material was taken as 1 with zero variance.
SPECIRA MATERIAL DU CI'.ILXIY MODELING F
median 1$0 1.0 1.77 1.0 1.6 028 0.14 0.10 0.
027 0.28 0.
0.17 0.
007 Reference/(NOTES)
AEP449 &RIZZO(4)
(2)
RIZZO (4)
Resultant 091 0.29 0.42 median values Values above are applicable to AuxiliaryBuilding steel columns The auxiliary building was designed (Ref. 6) based on a median ZPA acceleration design capacity requirement of 0.2g.
The ZPA capacity = seismic design capacity required times the median margin factor = 0.20~4.25 = 0.85g The ZPA HCLPF value is HCLPF(ZPA) = 0.85~e(-1.65*(0.31 + 0.29)) = 0.32g
D.C. COOK EQUIPMEKI'RAGIIXIY MSE-W'SIA12(94)
FRAGILZIY ES'I%M'ATE FOR STEEL COLUMNS INAUXILIARYBUILDING NOTES As noted above, the yield strengths of the column materials used in the strength analysis were based on millcert. tensile strengths of the individual steel columns; thus it is concluded that a deterininistic median strength factor equal to 1 is appropriate.
2.
References 10 and 11 describe the seismic response characteristics of the auxiliary building. It is clear from the auxiliary building floor spectra given in Reference 11 that the AuxiliaryBuilding has a fundamental frequency between 2 Hz and 3.3 Hz For the purpose of this evaluation, it is assumed that the steel median ductility was 2.0.
Since the structure is fiexible, damping also has an effect on the column response; a value of 5% was considered to be reasonable.
TABLE5-1 of Reference 3 was used to define the ductility factors used in this analysis.
3.
The variability in modeliug lies primarily in the ability of the analytical model to estimate system frequencies. For this evaluation the median factor was taken equal to
- 1. This evaluation follows the approach set forth in Reference 3. In this approach equation 4-33 of Reference 3 is used to estimate P; the value for modeliug can be calculated as follows:
P= ln(spectral acceler. at 85% exceedence probability frequency/spectra acceleration at median frequency).
The estimated median building frequency was taken as 2.5 Hz.
The 85% exceedence frequency has been calculated following the suggestion given on page 4-52 of Reference 3. The 85% exceedence frequency, f> is given by 2.5~e~.~ =
1.95 Hz Reviewing the fioor response spectra given in Reference 11 for 5% damping, it is clear that there is no significant change in the spectral value in this frequency range.
Indeed a frequency shift outside this range willresult in a drop in the spectral level.
From this it is clear that Pcan be set equal to P= 0.0 4.
The P values used were provided by RIZZO Associates, Reference 9.
D.C. COOK EQUIPMENT'FRAGILITY MSE-WSIA12(94)
DIESEL GENERATOR DIESEI FUEL DAYTANKMASONRYWALL INTRODUCTION The fuel day'ank is located in the diesel generator room at the 591'evel. It is enclosed by a masonry block wall which has been stiffened by the presence of an angle bolted to the inside face of the wall. The concern exists (Section 4.40 of Ref. 1) that the wall could fail during a seismic event and damage the day tank.
Reference 12 contains details related to the seismic design'of the wall. The wall consists of a 13'all parallel to the tank's long axis integral with 6 foot side walls at each end. The waH was assembled using DUR-0-WAL reinforcement placed at a sixteen inch spacing.
The wall is not supported at the top edge by the ceiling. The bending frequency, of the wall acting as a horizontal one way beam with fixed ends is 11 Hz.
A.wall stiffener beam consisting of one 5" angle is bolted to the inside of the masonry wall (Ref. 5 Appendix C page 301).. Since the stiffener is located only on one wall'face, it can develop only a limited amount of moment resistance at the wall base where it is connected to floor slab.
Since the tank level is above the AuxiliaryBuilding base, the HCLPF value must be lowered: the spectral values must be scaled to represent the free field ZPA value.
This factor is done in two stages: first the spectral value is scaled to be representative of the floor ZPA; and second, the fioor ZPA is scaled to be representative of the free Geld acceleration.
This factor (based on 2% spectral damping) is (0.22/0.29)"(0.2/0.22), and is equal to 0.69.
This factor is treated as deterininistic since two other parameters, spectzal effects and modeling effects, already take into account the variability of the earthquake and building dynamic characteristics.
BASIC WALLSTRENGTH The stiffener is bolted to the wall at the top and bottom and breaks up the wall into two panels (5'x10.16'nd the other 5'x3.17'). Since the angle connection to the floor has limited moment capacity, this restraint willnot be considered in this evaluation.
Since the wall continues around the tank sides, these corners willprovide additional bending restraint to the long wall. This strength reserve factor had not previously been considered in Reference 12.
To reduce the conservatism reported in References 1 and 12, the wall has been zeanalyzed.
For the purpose of the present evaluation, it is assumed that the wall can be modeled as a one way slab fixed at each end. Assume a one foot wide section of masonry wall spans the full distance of 13.33'.
Use the cross sectional properties given in Appendix A of Reference 12 to estimate the bending frequency of the wall acting as a one way slab.
The beam frequency is calculated using the following equation (Ref.13).
f = 3 56~[ EI/(mL')] = ll 2 Hz where E = 1.195~10'si I = 76.8 in'
= 13.33*12 = 159.96 in m = W/g = 5.5/386 = 0.0142 lb-sec~/in~
MSE-WSL412(94)
D.C~FCPOK PqUIPMENT FRAGILTIY i-:DIESEL GENERATOR DIESEL FUEL DAYTANKMASONRYWALL BASIC S'LENGTH cont.
Since no spectra is available for the 591'evel, this analysis willmake conservative use of the spectral curve for the 609'evel. It is assumed that the applicable spectral damping is 2% and the required spectral acceleration is 0.29g The ultimate strength of the DUR-0-WALmasonry is given in Reference 12 Ec 14. For an 8 inch wall constructed using R wire spaced at 16 inches, the ultimate resisting moment is 5694 in-lbs per foot of wall height (TABLE 15 of Ref. 14).
Considering a 12" height of wall with fixed ends, the maximum moment is M = a~W'L'/12 =. a~5.5*159.96'/12 =
a~11727 in-lb/ ft. of wall height where a defines the design g level used.
a = design seismic capacity = 5694/11727 = 0.49g FRAGILXIY P DUCTILITY MODELING F
median 1.09 1.054 1.0 1.3 028 0.02 0.13 0.01 0.13 0.20 028 0.13 0.02 0.13 020 Reference/(NOTES)
AEP450 &RxXZO(4)
Ref. 4, (1)
RIZZO (4)
Resultant 1.94 028 0.27 039 median values Values above are applicable to masonry wall at 591'evel The floor median spectral acceleration capacity,= seismic design capacity times median margin factor = 0.49~1.94 = 0.95g The HCLPF floor value is HCLPF(floor) = 0.95 "e(-1.65~(0.28.+ 0.33)) = 0.38g The free field median spectral acceleration capacity
= 0.95 ~ 0.69 = 0.66g For free field, the HCLPF value is HCLPF(free field) = 0.69 HCLPF(floor) = 0.69'0.43 = 0.26g
D.C. COOK EQUIPMEN'I'RAGILITY MSE-WSI 012(94)
DIESEL GENERATOR DIESEL FUEL DAYTANKMASONRYWALL NOTES For the DUR WALmaterial, the nominal yield strength is 70000 psi (Attachment B of References 12 and 14). For this case the controlling factor is steel yield. Now Table 1 (Steel Yield Strength Characteristics) of Reference 4 shows the mean and coefficient of variability (COV) for various steels.
The COV is defined as the ratio of the standard deviation divided by the mean value.
After reviewing the data on Table 1 of Reference 4 it was determined that reasonable values for these parameters
, mean and standard deviation (for a high strength material), are 1.1 and 0.13 respectively.
The material is defined in terms of the mean value and has been converted to median value using a relationship described in Equation 2.4 of Reference 1
F'= 1.1*e(-0.13'/2) = 1.09 2.
= The main source of ductility in the masonry wall during bending arises from the ductility of the DUR-0-WALsteel and its bond to the masonry.
For the purpose of this evaluation, it is assumed that the connection median ductility is 1.5. Due to the high calculated frequency for the wall, it is assumed that damping effects willnot effect ductility. TABLE5-1 of Reference 3 is used to define the ductility margin factors used in the fragility analysis.
3.
The variability in modeling lies primarily in the ability of the analytical model to estimate system frequencies. For this evaluation the median factor is taken equal to 1 since the models are adequate.,
This evaluation follows the approach set forth in Reference 3 and is used to define variability. In this approach equation 4-33 of Reference 3 is used to estimate P; the value for modeling can be calculated as follows:
P= In(spectral acceler. at 85% exceedence probability-frequency/spectra acceleration at median frequency).
The estimated median frequency was taken as 11 Hz; the system frequency has been defined. in Section 4.49 of Reference 1.
The 85% exceedence frequency has been calculate following the suggestion given on page 4-52 of Reference 3. The 85%
exceedence frequency, f> is given by 11*e~~ =
8.6 Hz Using the floor response given in Reference 2 and 2% damping, we have f = 11 HZ RRS = 0.29g fp = 8.6 Hz RRS = 0.33g and P= ln(0.33/0.29)
= 0.13 4.
The P values used were provided by RIZZO Associates, Reference 9 D.C. COOK EQUIPMERT FRAGIL7IY MSE-WSL-012(94)
CCW HEAT EXCHANGER SUPPORTS Anchorage The heat exchanger is mounted on a pedestal at each end, on the 609'oor elevation of the auxiliary building.
One pedestal has additional anchorage and the equipment is considered fixed, while the second end is free to slide to accommodate thermal growth. The heat exchanger is anchored by 2 J-Bolts on each pedestal, embedded into the floor concrete below the pedestal.
The J-Bolt has an embedment length of 24", before the bend, while the pedestal is 7" high, so the bend lies 17" below the concrete floor surface.
The equipment is welded to two saddle supports made up of angles which rest on a 1-1/2" thick layer of grout, which caps the pedestal top. The pedestal concrete edge distance is a mnnmum of 6".
Cracks have been found in a plane between the concrete and grout interface and on a number of vertical planes passing through the pedestals at each end.
The pedestals were'designed to provide for free axial thermal growth of the heat exchanger, one end was designed to be fixed while the other end could slide axially. The cracks found are inconsistent with the expected pedestal deformation under the design condition loads.
The cracking condition must have occurred due to normal deadweight and the tank heat up condition, since no seismic loading for which the pedestals were designed has yet occurred.
With the deadweight load of 40 kips at each support point and p ranging from 0.3 to 0.7 for steel on concrete, a
frictional shear load of 28 kips can be induced in the concrete before sliding, while resisting the thermal growth of the tank.
This load should be sufficient to crack the bond between surfaces.
As a result it is concluded that the cracking was produced by thermal heat up.
Thermal loads are self equilibrating and thus need not be additive to the design loads under the Faulted Condition; the presence of the thermal axial loads indicates that the sliding support was not free to slide.
Finally, the presence of the vertical cracks willnot effect the development of bending resistance, and the presence of the horizontal crack at the grout/pedestal interface is considered in this evaluation.
The strength of the interface between grout and concrete is maintained by the frictional resistance.
The resisting frictional force is equal to the deadweight or normal force at the support times the coefficient of friction. Using p = 0.6 from Section 11.7.4 of ACI-349, the V, = 0.6(40), but must not exceed 0.2f,'A, per Section 11.7.5 of ACI-349, using A, equal to the concrete area under the saddle.
The resulting shear capacity is the MIN@4, 157.5] or 24 kips.
D.C. COOK EQUIPMENI'RAGILETY CCW HEAT EXCIQAGER SUPPORTS Spectral Floor Acceleration Capacity MSE-WSL412(94)
Consider additional margins based on Ref. 18.
Reference 15 applies a pzying factor of two in the determination of the seismic design capacity based on anchor bolt tensile strength, for a median spectral floor acceleration capacity of 0.45g.
This factor is conservative since the weight of the heat exchanger willaid in reducing the liftingof the plate and therefoxe prying. A computer model of the base plate (saddle base) was developed with the stiffener plates represented.
Loads weze detezmined based on the seismic design capacity of Reference 15.
The anchor in tension has a pullout load of 10.13 kips, per Ref. 18.
The ultimate load willbe used as the steel capacity.
The steel capacity willbe considered to control over the concrete for tension since the J-Bolt is deeply embedded.
The capacityof the steel, F is S~ or 26.8 kips, where A, = 0.462 in.~,
S= 58 ksi.
A.factor of safety of 26.8/10.13 = 2.65 is obtained.
Shear-Tension interaction should also be considered. The concrete shear capacity for the free edge distance is (l.1)2(f,')'
m', from ACI-349 Appendix B, Section B.5.1.2 and Commentary, where m is the edge distance, f,'s the concrete compressive strength, and m is the distance to the free edge.
A minimum edge distance of 6" is applied and the strength is 14.7 kips per anchor bolt.
The ultimate shear strength for the anchor bolt steel is 0.42Sper the ASME Code, Appendix F, Section F-1335.2.
The capacity, F, is 0.42SA, or 14.64 kips, where A, = 0.601 in.,
considering the bolts to act in combination with load redistribution, the factor of safety for 0.45g loading is (2x14.64)/18 = 1.63.
The nominal bolt area is used since the bolt shear strength must be developed at the grout/pedestal interface, since the grout relies on frictional strength.
Drawing 12-3285-23 shows the thread ending at the grout/pedestal interface.
Consider parabolic shear/tension interaction similar to the ASME Code, NF-3324.6:
(1/2.65)~+(I/1.63)~ < 1.0 = 0.520-Obtaining a similar relationship in terms of variable A:
[(62.3AH - 13.33)0.689/FJ'
[80AH/2 = 1.0 a iterative solution of 0.587g is obtained, where A is the horizontal g value and the vertical g is assumed to be 2/3 A.
Scale Factor The median free field spectral acceleration capacity equals the median fioor spectzai acceleration capacity times a scale factor.
The heat exchanger is mounted at the 609'evel of the AEP auxiliary building, per Ref. 1, page 27.
The applicable fzcquency for the support is 33 Hz. and 2% damping is applied per Ref. 15 page 4. The nominal seismic spectral acceleration at the equipment frequency is 0.22g, equivalent to the floor ZPA since the support frequency resides in the rigid range.
The corresponding free field ZPA is 0.2g.
The scale factor is 0.22/0.22
~ 0.2/0.22 = 0.91 D.C. COOK EQUIPMEÃl'RAGILITY MSE-WSL-012(94)
CCW HEAT EXCHANGER SUPPORTS FRAGIIXI'YP 9UCHL'm'(2)
MATERIAL MODELING F
median 1.0 1.0
. OM 0.123 0
0.20 028 0.123 024 Refer encel(NO'IKS)
Resultant 2.0 097 median values Values above are applicable to the heat exchanger anchorage at the 609'evel The floor median spectral acceleration capacity = seismic design capacity times median margin factor = 0.587 2.0 = 1.17g, The HCLPF floor value is HCLPF(floor) = 1.17'(-1.65*(0.28 + 0.23)) = 0.50g The free field median spectral acceleration capacity
= 1.17
- 0.91 = 1.07g For free field, the HCLPF value is HCLPF(free field) = 0.91~ HCLPF(floor) = 0.91~0.50 = 0.46g
D.C. COOK EQUIPMENT FRAGILITY CCW HEAT EXCHANGER SUPPORTS
. MSE-WSL412(94)
NOTES UHS factor from Westinghouse Calc. No. AEP-050, Ref. 7.
Adjustment to reflect the conservatism of the DC Cook FSAR SSE ground Design Spectra w.r.t the LL'NL UHS 10,000 year median spectral shape.
Pr was provided in Ref. 9, by Rizzo Associates.
2.
Inelastic Energy Absorption Factor for the critical element, the anchor bolts.
See Note 3.
3.
From Westinghouse Calc. ¹ AEP-036, Ref. 15, the tensile capacity of the 7/8" diameter J-Bolt controls, over the conczete capacity indicating a ductile mode of failure. A reasonable conclusion-despite the cracking'f the pedestal, since'the J-Bolt is embedded in the concrete floor, and the shear capacity is not degraded by the cracks in the pedestal.
However, brittle failure must be considered as described in Section'5.1.1.1 of the Ref. 3.
Considering the system ductility, the inelastic energy absorption associated with the anchor bolts is small.
Since the supported equipment is massive, the equipment willtypically be stressed below the yield point, while the bolts are stressed at a level well above the yield point. The amount of inelastic energy absorption derived from the bolts is therefore minimal. Since the failure is considered brittle, a factor of 1.0 is applied.
4.
Similar.random strength material factors are found for the concrete and the steel.
Ref. 3, Section 4.1.1.1, page 4-8, provides an average value for strength increase due to aging and batch strength.
Table 4-1 provides values for fc = 3000 psi, but not for 3500 psi, per Ref. 15.
As a result, the value for 3000 psi willbe used.
Note that on page 4-10 of Ref. 3, it is stated that the strength may increase for the zate of loading at seismic response frequency, however the increase factor is cancelled by the in-place strength reduction factor.
This in-place strength reduction factor is based on the difference in strength between in place concrete and the test cylinder concrete.
For the steel, a mean factor of 1.189 can be found in Table 1 of Ref. 4, with a COV of 0.0871.
A median value of 1.18 is obtained, and a dynamic increase factor of 1.1 can be applied per Ref. 16, resulting in a median value of 1.3.
The concrete controls.
5.
Variability in modelling based on analytical model frequency estimates is not applicable since the pedestal and heat exchanger is rigid.
6.
From Ref. 9.
D.C. COOK EQUIPMEÃZ FRAGILXIY REFERENCES MSE-WSIA12(94) 3.
4, CJc AZP-025, "Auxili:myBldg Equipment Fragility," dated 12-05-91.
CALC AEP-032, "Seismic Margin for 600V and 4KV Switchgears," Dated 10-14-91.
Report No. 1643.02, "Seismic Fragilities of Civil Structures and Equipment Components at the Diablo Canyon Power Plant," September 1988.
ASME Conference-Pressure Vessel and Piping Technology Conference-A Decade of Progress, L. Greimann and F. Fanous,"Reliability of Containments Under Over Pressure,"
1985.
5.
6.
EQE Engineering Consultants, 52077.01'-R-002, Rev. 0, "Walkdown of Auxiliary Building in Support of Cook Nuclear Plant IPEEE, Units 1 and 2," 2 Volumes, January 1992.
AEP Calculation DC-D-30535-193, "Structural Design Section Calculations for AuxiliaryBuilding Steel Structure Part of Steam Generator Replacement Program,"
12/8/86.
7.
8.
9.
Calculation AEP-50, "LL'NLUNS Equipment Fragility Data," 11/20/91.
Calculation AEP-49, "Fragility Data - LLNLUNS Spectra Shape'izzo Associates Letter "Seismic Hazard Analysis, Donald C. Cook Nuclear Plant,"
08/17/94.
10.
12.
13.
14.
15.
Report from Rizzo Associates89-654, "Effects of ground Spectral Shape on Plant Response,"
Revision 1,Feb. 1992.
AEP Letter AEP-1955, "Seismic Design of Equipment Located AuxiRuy Building,"
Dated February 5, 1971.
Calculation AEP-029, "Seismic Margin, for various Masonry Walls, dated 10-91.
Rogers,G.L., "Introduction to the Dynamics of Framed Structures," John Wiley and Sons, 1959, Figure 5.8.
DURO-0-WALCatalog, "4 Unit Masonry Ties and Reinforcement,'-'/C 1979 Calculation AEP-036, "Seismic Margin for Various Components - CCW HX," Rev.
0, dated 12-91.
16.
R.S. Orr, Proposed Addition to: "Commentary on Code Requirements for Nuclear Safety Related Concrete Structures (ACI 349-76)," ACI Committee 349.
ASME Boiler and Pressure Vessel Code,Section III,Division 1, Subsection NF, and Appendix F, 1989 Edition.
D.C. COOK EQUIPMENT FRAGILITY MSE-WSL-012(94)
REEKP3BICES cont.
18.
Calculation No. CSE-08-94-0042, "AdditionalMargins for the CCW Heat Exchanger Suy~oW," Rev. 0, Aug. 1994.
ATTACHMENT2 AEP-94-760 NTD-NSRLA-OPL-94-214 F
AEPSC746/N SR'I
Report Number 1643.02 QA Report Humber 34001.01-R014 see
'I I
~ ~*)
SEISMIC FRAGILITIES OF CIVIL STRUCTURES AHO EQUIPMEHT COMPOHEHTS AT THE OIABLO CANYON POWER PLANT
~ ~0
/
w.
Q/
yi g 9/
Prepared For Pacific Gas and Electric Company One California Street San Francisco, California 94106 Prepared By T.R. Kipp O.A. Wesley O.K. Hakaki HTS Engineering 6695 East Pacific Coast H)ghway Long Beach, CA 90803 Fra++ity Consultant Or. R.P.
Kennedy RPK Structural Mechanics Consulting 18971 Villa Terrace Yorba Linda, CA 92686 September 1988
WestinghoUse Electric Corporation Energy Systems Nuclear Techno to my Division Box 355 Pittsburg Pennsytvanta 15230 0355 Mr. R. Bennett Nuclear Safety Section American Electric Power Service Corporation One Riverside Plaza Columbus, OH 43216M31 September 23, 1994
, AEP-94-785 NTD-NSRLAPL-94-285 AMERICANELECIRIC POWER SERVICE CORPORATION DONALDC. COOK UNITS 1 AND 2 Transmittal of ii Data Ref.:
1.
2.
3.
4 5.
AEPSC letter from R.B. Bennett to K.F. Matthews, 9/2/94 AEP-94-771 "Seismic Fragilities of Civil Structures and Equipment Components at the Diablo Canyon Power Plant," NTS Engineering, Report No. 1643.02, Sept. 1988.
AEP-94-760, 8/19/94 "Seismic Fragility Assessment, Donald C. Cook Nuclear Plants," Rev. 1, March 1993.
Dear Mr. Bennett:
Attached for your information and use are the seismic fragility data [median capacity (Am), Pr, Pu and high confidence in low probability of failure (HCLPF)] for the Task 1 items delineated in Ref. 2.
These data have been developed following the approach used by Diablo Canyon and described in Reference 3.
The Task 1 items for which fragilitydata are provided are:
1.
2.
3.
5.
6.
7.
Screen House Base Slab AuxiliaryPiping Supports Refueling Water Storage Tank Emergency Diesel Generator, Transformers (Wall controls)
Emergency Diesel Generator, Motor Control Center Essential Service Water Pumps Pressurizer PORV's (generic data review)
Also provided for completeness are the fragilitydata previously transmitted in Reference 4 for:
1.
2.
3.
4, Masonry wall around EDG Diesel Fuel Day Tank 4 KV switchgear anchorage CCW HX supports including cracks identified during the A46 walkdown AuxiliaryBuilding
AEP-94-785 NTD-NSRLA-OPL-94-285 September 23, 1994 Note that the median capacity of the masonry wall around the EDG Diesel Fuel Day Tank has been corrected (value changed from 0.95g to 0.66g) from that given in Reference 4.
RSL/bbp cc:
J. Kingseed D. Malin R. Lapides E. Lewis
- AEPSC T. Georgantis
- AEPSC.
- AEPSC
- AEPSC
-W Comparisons of the revised fragilityvalues are made with the "old" values documented in Reference 5 are given on'he attached sheet.
Ifyou have any questions or comments, please call'Robin Lapides (412/374-5683) or me.
Very truly yours,
(
, Keith F.
atthews Senior Sales Engineer, Power Systems Field Sales
Task 1 equipment fragilitydata.
COMPONENT REVISED VALUES HCLPF OLD VALUES Pu HCLPF pr pu Screen House Base Slab AuxiliaryPiping Supports Refueling Water Storage Tank EDG Transformer Wall EDG Motor Control Center 0.35g 0.31g OAOg 0.33g 0.22g 1.06g
'.81g 0.95g 0.79g 0.64g 0.31 0.31 0.31 0.28 0.34 0.35 0.34g 0.28 0.30g 0.21 0.37g 0.25 0.36g 0.30 0.22g 0.44g 0.16 0.00 0.44g 0.23 0.00 0.44g 0.10 0.00 0.3 8g 0.048 0.00 0.29g
- 0. 17 0.00 Essential Service water Pumps 0.45g 1.13g 0,31
~
0.25 0;39g 0.46g 0.10 0.00 Pressurize PORV's (~)
0.47g 1.68g 0.20 0.57 0.31g 1.29g 0.26 0.60 The fragilitydata for the PORV are based on generic fragilitydata.
The old data are from NUREG/CR-3558, and the new data from NUREG/CR-3892.
The standard deviation values pr and pu are essentially the same; the higher capacity reficcted by NUREG/CR-3892 is duc to the higher Am value given. It is noted that ifthe seismic capacity is based on the UHS spectra, then Am and HCLPF can be increased by 1.3.
Previously provided seismic fragility data.
COMPONENT REVISED VALUES HCLPF OLD VALUES Pu HCLPF Masonry Wall (EDG Fuel Day 0.26g Tank) 4 KV Switchgear Anchorage 0.58g 0.66g 0.28 1.77g 0.31 0.27 0.25g 0.37 0.55g 0.27g 0.05 0.66g
- 0. 10 0.00 0.00 CCW HX Supports AuxiliaryBuilding 0 46g 0.32g 1.07g 0.28 0.85g 0.31 0.23 OASg 0.29 0.30g 0.54g 0.10 0.38g
- 0. 13 0.00 0.00
Westinghouse Electric Corporation Energy Systems Huclear Technology Oivislon Box 355 Pittsburth Pennsylvania 15230 0355 Mr. R.B. Bennett Nuclear Safety Section American Electric Power Service Corporation One Riverside Plaza Columbus, OH 43216M31'ctober 3, 1994 AEP-94-789 NTD-NSRLA-OPL-94-300 Ref: 1. AEP-94-771 AMERICANELECTRIC POWER SERVICE CORPORATION DONALDC. COOK NUCLEARPL4fl' lementa Seismic Fra ili Estimation
Dear Mr. Bennett:
Attached for your information and use is the summary report for the supplementary seismic fragility estimation for the Donald C. Cook Nuclear Plant.
This completes the deliverable described in Reference 1
for the Task 1 items.
Per your request, Task 2 (Reference
- 1) was removed from the scope of effort, since the component cooling water piping system was included in their ongoing snubber reduction program.
Assessing the effect of snubber failures within this line on plant seismic capacity has no meaning since the snubbers of issue are being removed.
The additional soil liquification analyses and soil slope stability evaluations are still ongoing (Reference 1,
Task 3). This work is being performed by Rizzo Associates.
Currently, Rizzo Associates is waiting for input from AEPSC.
Ifyou have any questions or comments, please call Robin Lapides (412/374-5683) or me.
Very truly yours, RSL/bbp Attachment Ke th
. Matthews Senior Sales Engineer Power Systems Field Sales cc:
J. Kingseed - AEPSC D. Malin - AEPSC N. Vaidya - Rizzo Associates T. Georgantis - AEPSC E. Lewis - AEPSC AEP7S9INSRLAXOl
Supplementary Seismic Fragility Estimation Donald C. Cook Nuclear Plants cirrose Additional seismic fragility estimation was requested by the NRC staff to supplement the information previously provided as part of the plant PRA IPEEE. Specifically, of issue is the methodology used in the evaluation of component fragilities. The NRC staff has requested further component seismic fragility analyses including both random and uncertainty variability following similar methodology that is used for the evaluation of Diablo Canyon (Reference 1). This evaluation is to be based on realistic behavior and not conservative assumptions.
The purpose of this supplementary seismic fragility assessment is to demonstrate that the process and methodology used for the Donald C. Cook Nuclear Plant IPEEE (individual plant examination of external events) program to identify seismic vulnerabilities did not mask the importance of nonseismic failures, operator recovery actions, or effect the ranking of dominant sequences and contributors.
~Sco e
The scope of this investigation is limited to those components identified during the NRC audit (4 KV switchgear anchorage, component cooling water heat exchanger [CCW HX] supports, reactor coolant system pressurizer relief valve [PORV]), and important components with high confidence in low probability of failure (HCLPF) values less than 0.4g.
The selection of components with HCLPF values less than 0.4g for further evaluation is based on the 1993 seismic fragility results on which the plant PRA IPEEE program is based.
This is acceptable because:
o the HCLPF values are a measure of importance with respect to seismic ranking and dominant contiibutots; o
the HCLPF values are found in the these supplementary analyses to be basically unchanged following Reference 1 methodology, and therefore, remain important components with respect to defining plant seismic capability.
~
The PORV is included even though its seismic capacity is based on generic fragilitydata, because the NRC thought that the Pu value is large (0.60). The CCW HX support is included because cracks were found during the SQUG walk down activity after the completion of the seismic fragility analysis.
The cracks are in a plane between the concrete and grout interface, and on a number of vertical planes passing through the pedestal at each end.
Eleven components were selected and ate listed below:
1.
Screen House Base Slab 2.
Piping Supports 3.
Refueling Water Storage Tank 4.
Emergency Diesel Generator,-Transformers (Wall controls) 5.
Emergency Diesel Generator, Motor Control Center
6.
Essential Service Water Pumps 7.
Pmsutizer PORV's (generic data review) 8.
Masonry wall around EDG Diesel Fuel Day Tank 9.
4 KVswitchgear anchorage 10.
CCW HX suppo'its including cracks identified during the SQUG plant walkdown 1 I.
AuxiliaryBuilding The NRC staff had asked ifhigher seismic capacity of the component cooling water piping system could be shown assuming failure of the snubbers having,a low seismic capacity (HCLPF = 0.24g).
However, this task was not preformed because this piping system has been included into the AEPSC on-going snubber reduction program.
The subject snubbers are being removed and replaced by other types of supports which will increase the piping system seismic capacity.
Methodology Seismic fiagilitydata [median capacity (Am), Pr, Pu and high confidence in low probability of failure (HCLPF) for the identified scope were developed following the approach used for Diablo Canyon and described in Reference
- 1. To develop the fragility data, design/analysis reserve margin factors along with their standard deviations were defined for each of the components and structures.
The margin factors employed can be grouped into five general categories as described below:
Spectral Shape Soil-Structure Interaction Material Ductility Modeling Each of these are discussed below.
Spectral Shape In Reference 3, Section 3.1.1.2 it is stated:
Most seismic PRA's use peak ground acceleration as the hazard parameter. Ifthis is done, spectral shapes that are consistent with current estimates of ground motion should be used.
In the Central and Eastern United States, curtent spectral estimates can be found in the LLNL and EPRI hazard studies.
Since similar spectral shapes ate obtained from LLNLand EPRI hazard studies, separate analyses using both spectral shapes are not needed.
Median spectral.
shapes of 10,000 year return period provided in NUREG/CR-5250 preference 4] along with.
variability estimates are recommended for use in the analyses...."
In Figure 1, a comparison is shown of the plant design ground spectrum and 10,000 year LLNL (Lawrence Livermore National Laboratory) median Uniform Hazard Spectrum (UHS) for the Donald C. Cook site. The spectra are normalized to the plant DBE level.of 0.2g and are associated with 5%
damping.
Margin factors were developed based on the plant seismic design response spectra.
These margin factors aiu determined by the difference in component seisttiic response as defined by the difference in the plant design seismic spectra and the plant spectra associated with the UHS. For the Donald C. Cook plant site these factors.,are all equal to or above one, since the significant seismic
response of. the structures and components are in the frequency range where the plant specific ground design response spectrum envelope the 10,000 year median UHS.
The random uncertainty in the response results from the earthquake to earthquake differences in ground motion which account for the variability in the spectral shape peaks and valleys.
On the basis of the SSMRP analysis documented in Reference 2, a seismic fragilityestimate is defined for structures and equipment referenced to peak ground acceleration levels. A randomness variability of 0.28 (pr = 0.28) over the entire frequency range of interest is defined. It is noted that a margin factor of 1.0 is assumed associated with the response results that account for the specific ground spectral shape.
Soil-Structure Interaction t
These margin factors (resporise"factors) are functions of modeling of the soil-structure interaction effect.
The median response can be approximated on the basis of the design response by using response factors which account for conservatism in the design methodology.
Of the several factors that lead to this conservatism, two factors are most important and are considered.
They are:
1.
the manner in which foundation embedment and wave incoherence was treated in the
- soil-structure interaction analysis, and 2.
the method used to account for soil-structure interaction radiation damping.
Modeling uncertainties are a function of the structure-specific response factors accounting for the subsurface conditions at the site.
Factors, with uncertainties, were defined for the structures and components within the scope of this assessment.
They ate:
o Containment Building/Internal Structure o
Auxiliary/diesel Building o
Pump/Screen House o
Refueling Water Storage Tank These structures are discussed individually below.
It is noted that structure specific response factors account for the subsurface conditions at the site. The finished genie at the plant site is 608'". The site subsurface consists of about 15 feet of fill underlain by very dense slightly cemented fine to medium sand approximately 35 feet in thickness between Elevations 594'" and 556'". This is underlain by a 50 foot layer of hard to very stiffsilty clay on a very compact tillstratum.
Plant structures are founded on the dense sand layer. The response factors associated with soil-structure interaction assumes a simplified soil profile represented by a 110 foot soil layer with a characteristic shear wave velocity of 1000 feet per second overlying bedrock.
- Containment Building/Internal Structure The Containment Building/Internal Structure is supported on a foundation mat that is about 140 feet in diameter.
The bottom of the foundation is at an average Elevation of574'". The design evaluation used a soil shear modulus of 2.880 kips/ft (approximate shear wave velocity of 1,000 ft/sec) and a soil
damping of 5 percent in the soil-suucture interaction analysis.
Additionally, the design analysis conservatively appTied the control motion at the foundation elevation.
The embedment ratio (embedment depth/structure radius) is about 0.45. The soil-structure interaction damping has a likelihood to be as high as 15 to 20 percent.
- Auxiliary/Diesel Building The Auxiliary/Diesel Building has an equivalent foundation radius of 138 feet and an average embedment of 34 feet. The embedment ratio is 0.25.
The design analysis assumed fixed base conditions in calculating the building seismic forces.
This assumption was found to yield conservative seismic loading.
Soil-structure interaction was included in a subsequent calculation to obtain floor response spectra for equipment evaluation.
The soil-structure interaction analysis used a soil shear modulus of 2,880 kip/ft (approximate shear wave velocity of 1,000 ft/sec) and soil damping of 20 percent.
The control motion was applied at the foundation elevation and the effects of wave incoherence were not included.
- Pump/Screen House The Pump/Screen House is substantially an embedded concrete shear wall structure with an above grade steel building enclosing the Pump House.
The Pump/Screen House structure is about 210 feet by 108 feet in plan.
Its foundation is approximately 40 feet below grade which is at elevation 580'".
The Response Reduction Factors for the Pump/Screen House associated with soil structure interaction are based on the assumption that the design seismic analysis included some soil-structure interaction,
'ut did not include the effects of the embedment.
The embedment ratio is 0.37.
Variation of ground motion through the embedment depth and the attendant wave scattering effects an: expected to result in a reduction of the seismic response calculated on the basis of the conservative assumption that the control motion is applied at the foundation elevation.
No response reduction is taken for radiation damping.
- Refueling Water Storage Tank The Refueling Water Storage Tank is an above grade structure supported on a concrete mat. The tank is 48 feet in diameter with a liquid height of 31 feet.
A fixed base analysis resulted in a fundamental frequency of about 5.5 hz.
Consistent with the foundation compliance for a rigid base, the natural frequency of the foundation mass in the horizontal soil-structure mode is about 15 hz.
On the basis of these results, the foundation is rigid relative to the structure, and the assumption of a fixed base for the seismic analysis is appropriate.. Therefore, the effects of soil structure interaction on the seismic response of the Refueling Water Storage Tank is ignored.
In Table 1 are provided the estimates of the mponse factors and modeling uncertainties for the individual structures and equipment contained within.
Material I
A material strength factor is used that accounts for the difference between code mandated minimum material values used for design and the actual material properties.
The factors that are used consider:
o material construction (steel or concrete)
o
~ cgiticaLfailure mode associated with the component or structure o
material properties used in the design and qualification analyses o
dynamic loading response characteristics.
Recognized material reserve margin fragility parameters (median and coefficient of variation) available from the public literature are used (eg., Reference 5).
As used in the Diablo Canyon analyses, the standard deviation is considered to be related to uncertainty Ductility The margin factor used for ductility reflects the reserve strength in a structure due to energy absorption caused by inelastic response.
Ductility fragility parameters as defined in Reference 1 are used.
The factors were chosen using the following approach:
o define failure mode and determine ifsufficient energy absorption willoccur due to system ductility to justify inclusion; ifnot, then brittle failure is defined and there is no reserve margin attributed to ductility; determine ifsystem (component) response is in the amplified or rigid region; in the rigid region damping has little effect; define reasonable median ductility factor (note that 5% damping is considered for response in the amplified region, this is a reasonable value);
based on amplified or rigid component response region, median ductility factor, and damping, determine the ductility factor and associated standard deviations associated with randomness and uncertainty as given in Reference 1; this factor is adjusted to reflect hysteretic (pinching) effect when appropriate (eg., concrete structures);
hysteretic adjustment (reduction in ductility factor of safety) is based on recommendations given in Reference 1 following the Riddell-Newmark approach:
Fp =
1 + CD(Fp' 1)
I
- where, CD = 0.6 correction factor Fp = median ductility factor adjusted for hysteretic effects Fp' median ductility factor that has not been adjusted for hysteretic effects.
Modelling The fragility paruneters associated with modeling are based on the ability of the analytical model to give realistic/conservative seismic response characteristics.
The significant factors that contribute to model variability are described below. They ate used as appropriate.
o Analytical model frequency
VpriabHity is defined following section 4.1.3 of Reference
- 1. An estimate of uncertainty standard deviation is defined as the natural log of the ratio of the spectral acceleration at 84% exceedence probability frequency and the spectral acceleration at the median frequency.
o Mode shape variability This factor is also discussed in section 4.1.3 of Reference
- 1. It is applicable where the model is used to estimate system response.
o Damping A damping factor is used when the analysis (analytical model) has used a conservative damping value.
Care is taken to wsure that this factor has not already been reflected in the ductility margin factor. This factor is discussed in Reference 1, section 5.1.1.2.
Results and Conclusions The results are presented in Table 2. The components and structures am arranged in the table in ascending order of "original" HCLPF values with the exception of the pressurizer PORV. The PORV fragility data are placed at the end of the table since the fragility parameters are based on generic data.
The following conclusions are made related to the fragility data summarized in Table 2 developed following the Diablo Canyon methodology.
0 The revised HCLPF values are essentially the same as the original values.
The largest differences are the EDG transformer wall which has the only lower HCLPF value which is only 8% lower than the original HCLPF value, and the essential service water pumps whose HCLPF value is only 15% higher.
The small change in HCLPF values is expected because the fragility parameters used in the PRA IPEEE analysis:
yielded lower bound estimates of the HCLPF values, recognizing that realistic values will not be far removed; used margin factors that have a deterministic basis, and not factors based on engineering judgement that may unrealistically bias the results; reflected spectral shape variability since they were based on plant specific spectra and not the 10,000 year median Uniform Hazard Spectrum.
Further, the sensitivity studies previously performed and documented in past submittals (AEP:
NRC 1082G, question 17) showed that the HCLPF values do not significantly change when margin factors with appropriate standard deviations are introduced to reflect other factors not considered.
These factors were not used in the development of the original fragilitydata in order that "lower bound" HCLPF would be reflected in the plant PRA IPEEE results.
o The ratio of revised median capacity and the HCLPF value is between 2.3 and 3.
The fngijitydata for the PORV are based on generic fragility data.
The old data are from NUREG/CR-3558, and the new data from NUREG/CR-3892.
The standard deviation values, Pr and Pu, are essentially the same; the higher capacity refiected by NUREG/CR-3892 is due to the higher median capacity given. The fragility data used in the IPEEE PRA for the PORV is considered appropriate since the use of generic data is acceptable, but there is no basis to use a higher capacity.
Based on the results summarized above, the following conclusions can be made related to the purpose of this investigation to demonstrate that the process and methodology used in the IPEEE program to identify seismic vulnerabilities did not mask the importance of nonseismic failures, or operator recovery actions, or effect the ranking of dominant sequences and contributors.
Significant change in the fragility data is the median capacity, and the Pr and Pu values.
The increase in median capacity was fairly uniform between 2 and 2.5 (rounded off). Since the HCLPF values remain essentially the same as calculated from the original fragility data, and the median capacities increase, the core melt frequency as well as component/structural failure probability at higher seismic levels will be lower than obtained using the original fragility data It was found from the PRA IPEEE results and the sensitivity study previously. reported, that the HCLPF values are representative of the order of ranking.
Therefore, since the revised HCLPF values are essentially the same, the dominant contributors will remain the same, and the ranking of the dominant contributors will remain the same or change insignificantly.
The same conclusion is reached as reported in the referenced sensitivity study. The results of the seismic PRA are conservative and the dominant contributors willnot change.
No nonseismic failures or operator recovery actions are masked.
The IPEEE seismic analysis and the seismic fragility data used for it are appropriate for satisfying the requirements of NUREG-1407.
References 1.
"Seismic Fragilities of Civil Structures and Equipment Components at the Diablo Canyon Power Plant," NTS Engineering, Report No. 1643.02, Sept. 1988.
NUREG/CRP331, "Simplified Seismic Probabilistic Risk Assessment:
Procedures and Limitations," Lawrence Livermore National Lab., Ca., UCID-20468, August, 1985.
3.
NUREG-1407, "Procedural and Submittal Guidance for the Individual Plant Examination of External Events gPEEE) for Severe Accident Vulnenbilities," Final Report, U.S. Nuclear Regulatory Commission, June 1991.
NUREG-5250, "Seismic Hazard Characterization of 69 Nuclear Power Plant Sites East of the Rocky Mountains," Vols. 1-8, January 1989.
5.
Greimann, Lowell and Fouad Fanous, "Reliabilityof Containments Under Overpressute,"
Pressure Vessel k Piping Technology, A Decade of Progress, 1985.
100 10, CJ Lal M
z,
/p
~ ~
~
Prr+i
~o
~KNt'H Vci 0.2C OiuPwC Sr.
COOK SSE:
r I
G CD 1.0
~/'"a 0
~
10
.~O cP 4 0.1.01 0.1 1.0 FREQUENCY (Hz) 100 Legend:
Cook SSE:
Ground Design Response Spectrum LLNLUHS: Lavnence Livermore National Laboratory 10,000 year Median UHS Figure I - Comparison of Plant Design Ground Spectrum and 10,000 year Median Uniform Hazard Spectnm for the Donald C. Cook Site
Table I Soil Structure Interaction Effects
Response
Factors and Modeling Uncertainties Structure Building
Response
Factor Equipment
Response
Factor Containment Building/Internal Structure
- SSI Embedment
- SSI Damping Auxiliary/Diesel Building
- SSI Embedment
- SSI Damping Pump/Screen House L
- SSI Embedment
- SSI Damping Refueling Water Storage Tank 126 1.00 137 0.15 0.00 027 0.00 027 0.00 125 1.67 130 1.00 130 1.00 0.15 022 020 0.00 020 0.00
- SSI Embedment
- SSI Damping 0.00 0.00 Table nomenclature:
SSI = Soil Structure Interaction Pu = Standard deviation associated with uncertainty
Table 2 Seismic Fragility Parameter Summaries COMPONENT REVISED VALUES ORIGINALVALUES EDG Motor Control Center Masonry Wall (EDG Fuel Day Tank)
Auxiliary Building Piping Supports Screen House Base Slab EDG Transformer Wall Refueling Water Storage Tank Essential Service water Pumps CCW HX Supports 4 KV Switchgear Anchorage HCLPF 022g
,026g 032g 0.31g 035g 033g 0.40g 0.45g 0.46g 0.58g 0.64g 0.34 0.66g 0.28 0.85g 031 0.8lg 0.31 1.06g 0.31 0.79g 0.28 0.95g 0.31 1.13g 0.31 1.07g 0.28 1.77g 0.31 HCLPF 0.30 0.22g 027 0.25g 029 030g 0.28 030 g 0.35 034g 025 0.36g 0.21 037g 025 039 g 0.23 0.45g 0.37 055g 0.29g 0.27g 0.38g OA4g 0.44g 0.38g 0.44g 0.46g 0.54g 0.66g (r
Pu 0.17 0.00 0.05 0.00 0.13 0.00 0.23 0.00 0.16 0.00 0.048 0.00 0.10 0.00 0.10 0.00 0.10 0.00 0.10 0.00 Pressurizer PORV's 0.47g 1.68g 0.20 057 031g 1.29g 0.26 0.60 Table nomenclattue HCLPF = component/structure high confidence in low probability of failure de6ned as, HCLPF = Am d'~i" >>t Am = component/structure median seismic capacity Pr
= standard deviation attributed to randomness variability Pu standard deviation attributed to uncertainty variability 10
APPENDIX B SEISMIC INITIATINGEVENT {}UANTZPZCATZON POR EACH EVENT TREE
( Note: This Appendix contains computer output.
It was not included to reduce the volume of the submittal.)
- I4,~ ~ r
<<t s I
.1w P
APPENDIX C QUAJiTIFICATIONOUTPUT FOR SEISMIC CORE DAMAGEFREQUENCY
( Note: This Appendix contains computer output.
It was not included to reduce the volume of the submittal.)
APPENDIX D CORRECTION OF SEISMIC CORE DAMAGEFREQUENCY AND RISK REDUCTION KQKINGS FOR HIGH CONDITIONALFAIIURE SEISMIC SUBINTERVALS
~
4
Description of Calculation The uncorrected core damage frequency is taken from the interval.OUT files. It had been calculated in the WALTcode by summation of the individual cutsets. This is divided here by the initiation event frequency to calculate the conditional failure rate (labeled uncorrected ratio).
Since simple summation of the large failure rates is inappropriate, the top five cutsets are used to reevaluate the correct summation. The basic events and their failure rates are listed.
These failure rates are summed, and the sum is subtracted from the uncorrected ratio to find an equivalent failure rate for the remaining basic events (or combinations of basic events) which are not specifically listed. In a couple of instances, the remainder is a small negative number, which can be attributed to roundoff error.
The corrected conditional failure rate (labeled corrected ratio) is now calculated using the appropriate equations r = I - g (l-fg, where f, are the basic event failure rates (including the "remaining" basic event).
The corrected core damage frequency is calculated by multiplying this corrected ratio by the initiating event frequency.
For each basic event, the risk reduction is calculated.
The risk reduction is the reduction in core damage frequency ifthe basic event were not to fail. It is calculated by calculating a conditional core damage frequency as above with the basic event failure rate set to zero, and subtracting this from the conditional failure rate.
The reduction in core damage frequency Is then calculated by multiplying this result by the initiation event frequency.
Note that the sum of these risk reduction ratios does not equal unity, since there is significant overlap in the failures.
9-2
Correction of event frecpxencies Interval 2e uncorrect losp cdf 3.978-07 ief 6.828-07 ratio
- 0. 582111 basic event fail rate S-AUX-BLDG-PA 0.187 S-OT"11-FA 0.097 S-BR-250VDC-PA
, 0.097 S-B-250VDC-PA 0.097 S-BC-250VDC-FA 0.023 remaining
- 0. 081111 corrected 3.158-07 0.462583 import
- 0. 123612 0.057729 0.057729 0.057729 0.012652 0.047438 cdf reduc 8.43E-08 3.94E-OS 3 948-08 3.94E-OS 8.638-09 3.24E-08 Interval 2e slb cdf ief ratio basic event S-AUX-BLDG-PA S-OT-11-PA S-FODT-1AB/CD-PA remaining Interval 2e slo cdf ief ratio basic event S-AUX-BLDG-PA S-OT-11-PA S-PODT-1AB/CD-PA remaining Interval 2e sws cdf ief ratio basic event S-AUX-BLDG"FA S-OT-11-PA remaining uncorrect 58-08 8.86E-08 0.564334 fail rate 0.187 0.097 0.242 0.038334 uncorrect 4.04E-OS 7.198-08 0.561892 fail rate
- 0. 187 0.097 0.242 0.035892 uncorrect 2.388-08 5.62E-08 0.423488 fail rate 0.187 0.097
- 0. 139488 corrected 4.12E-08
- 0. 464855 import
- 0. 12309 0.057485
- 0. 170851 0
0 0.021332 corrected 3.33E-08 0.463495 import
- 0. 123403 0.057631 0.171285 0
0 0.019973 corrected 2.07E-08 0.368264 import 0 ~ 145307 0.067861 0
0 0
0.102403 cdf reduc 1.098-08 5.09E-09 1.51E-08 1.898-09 cdf reduc 8.87E-09 4.148-09 1.23E-08 0
0 1.448-09 cdf reduc 8.17E-09 3.81E-09 0
0 0
5.76E-09 Interval 2e llo cdf ¹ ief ratio basic event S-AUX-BLDG-PA S-PODT-1AB/CD-FA remaining
¹ 4.7e-9 removed uncorrect 1.678-08 3.38E-08 0.494083 fail rate 0.187 0
0.242 corrected 1.438-08 0.423854 import cdf reduc 0.132521 4.488-09 0
0 0.183941 6.228-09 0
0 0
0 0.040108 1.36E-09 0.065083
- overlapping cutsets 23 D-3
C
<<=
e
corrected 2.1E-07 Interval 3a uncoxrect losp cdf 3.03E-07 ief 3.26E-07 ratio 0.929448 basic event fail rate S-AUX-BLDG-PA 0.272 S-OT-11-PA 0.159 S-BR-250VDC-FA
- 0. 159 S-B-250VDC-FA 0.159 S-BC-250VDC-PA
'36 remaining 0.144448 0.642856 import 0.133438 0.067522 0.067522 0.067522 0.013337 0.060299 Corx'ection of event frequencies cdf reduc 4.35E-OS 2.2E-08 2.2E-OS 2.2E-08 4.35E-09 1.97E-08 Interval 3a slb cdf ief ratio basic event S-AUX-BLDG-PA S-OT-11-PA S -FODT"1AB/CD-PA remaining Interval 3a slo cdf ief ratio basic event S-AUX-BLDG-PA S-OT-11-PA S-PODT-1AB/CD-PA remaining uncorrect 4.99E-08 6.16E-OS 0.810065 fail rate 0.272 0.159 0 '09 0 '70065 uncorrect 4.77E-08 5.8E-OS 0.822414 fail rate 0.272
- 0. 159 0.309
- 0. 082414 corrected 3.74E-08 0.606579 import 0.146993 0.074381
- 0. 175929 0
0 0.029642 corrected 3.55E-OS
- 0. 611803 import
- 0. 145041 0.073393
- 0. 173593 0
0 0.034866 cdf reduc 9.05E-09 4.58E-09 1.08E-OS 1.83E-09 cdf reduc 8.41E-09 4.26E-09
- 1. 01E-08 2.02E-09 Interval 3a sws cdf ief ratio basic event S"AUX-BLDG-FA S-OT-11-PA uncorrect 3.22E-OS 4.52E-08 0.712389 fail xate 0.272 0.159 remaining 0.281389
+ combined w/ other failures corrected 2.53E-08 0.560032 import 0.164384
- 0. 083181 0
0 0
0.17228 cdf reduc 7.43E-09 3.76E-09 0
0 0
7.79E-09 Interval 3a llo cdf ¹ ief ratio basic event S-AUX-BLDG-FA S -PODT "1AB/CD-FA remaining
¹ 3.3e-9 removed corrected 1.86E-08 uncorrect 2.24E-OS 3.58E-08
- 0. 625698 fail rate 0.272 0
0.309 0.519437 import 0 '79551 0
0.214897 0
0 0.022485 0.044698 overlapping cutsets 26 cdf reduc 6.43E-09 7.69E-09
- 8. 05E-10 D-4
I
Correction of event frequencies 1nterval 3b uncorrect losp cdf 1.96E-07 ief 1.45E-07 ratio 1.351724 basic event fail rate S-AUX-BLDG-PA 0.365 S-OT-11-FA 0.212 S-BR-250VDC-FA 0.242 S-B-250VDC-PA 0.242 S-BC-250VDC-PA 0.055 remaining 0.235724 corrected
- 1. 15E-07 0.792356 import
- 0. 119355 0.055864 0.066293 0.066293 0.012085 0.064043 cdf reduc 1.73E-08 8.1E-09 9.61E-09
- 9. 61E-09 1.75E-09 9.29E-09 Interval 3b slb cdf ief ratio basic event S-AUX-BLDG-FA S"OT-11-PA S-FODT-1AB/CD-FA remaining Interval 3b slo cdf ief ratio basic event
'S-AUX-BLDG-PA S>>OT-11-PA S -PODT-1AB/CD-FA remaining uncorrect
- 4. 19E-08
- 3. 9E-08 1.074359 fail rate 0.365 0.212 0.382
- 0. 115359 uncorrect 4.16E-08 3.88E-08 1.072165 fail rate 0.365 0.212 0.382
- 0. 113165 corrected 2.83E-08 0.726438 import 0.157244 0.073598 0.169095 0
0 0.035673 corrected 2.82E-08 0.72576 import
- 0. 157634 0.07378 0.169514 0
0 0.034995 cdf reduc 6.13E-09 2.87E-09 6.59E-09 1.39E-09 cdf reduc
- 6. 12E-09 2.86E-09 6.58E-09 1.36E-09 Interval 3b sws cdf ief ratio basic event S-AUX-BLDG-FA S-OT-11-FA S"PODT-1AB/CD-PA*
uncorrect 3.82E-08 3.6E-08
- 1. 061111 fail rate 0.365 0.212 0.27 remaining
- 0. 214111
- combined w/ other failures corrected 2.57E-08 0.712933 import cdf 0.165007
- 0. 077231
- 0. 106176 0
0 0.07821 reduc 5.94E-09 2.78E-09 3.82E-09 2.82E-09 Interval 3b llo cdf ¹ ief ratio basic event S"AUX-BLDG-,PA S-PODT-1AB/CD-PA remaining
¹ 4.7e-9 removed corrected 2.2E-08 uncorrect 2.84E-08 3.44E-08 0.825581 fail rate 0.365 0
0.382 0.638408 import 0.207844 0
0.223509 0
0 0.030838
- 0. 078581 overlapping cutsets 23 cdf reduc 7.15E-09 7.69E-09 0
0 1.06E-09 Ec D-5
~
"a
Correction of event frecpxencies Interval 3c uncorrect losp cdf 1.98E-07 ief 7.86E-OS ratio 2.519084 basic event fail rate S-AUX-BLDG-FA 0.577 S-OT-11-FA 0.345 S-BR-250VDC-FA 0.46 S-B-250VDC-PA 0.46 S<<BC-250VDC-PA 0.097 remaining 0.580084 corrected 7.62E-OS 0.969365 import
- 0. 041788 0.016136 0.026097 0.026097 0.003291 0.04232 cdf reduc 3.28E-09 1.27E-09 2.05E-09 2.05E-09 2.59E-10 3.33E-09 Interval 3c slb cdf ief ratio basic event S-AUX-BLDG-PA S-OT-11" PA S-PODT-1AB/CD-PA S-IC-ZCE-BASB-PA remaining Interval 3c slo cdf ief ratio basic event S-AUX-BLDG-PA S-OT-ll-PA S"PODT-lAB/CD-PA S-ZC-ZCE-BASB-PA remaining uncorrect 9.07E-08 5.29E-OS 1.714556 fail rate 0.577 0.345 0.5 0.14 0
0.152556 uncorrect 7.59E-OS 4.43E-08 1.713318 fail rate 0.577 0.345 0.5
- 0. 14
- 0. 151318 corrected 4.76E-08 0.899037 import 0.13772 0.053179 0.100963 0.016436 0
- 0. 018175 corrected 3.98E-OS 0.89889 import 0.137921 0.053257 0 10111 0.01646 0
0.018028 cdf reduc 7.29E-09
- 2. 81B-09 5.34E-09
- 8. 69E-10 9.61E-10 cdf reduc 6.11B-09 2.36E-09 4.48E-09 7.29E-10 7.99E-10 Znterval 3c sws cdf ief ratio basic event S-AUX-BLDG-FA S-OT-ll-PA S-FODT-1AB/CD-PA>>
S-IC-ZCE-BASB-FA uncorrect
- 1. 14E-07 5.29E-08 2.155009 fail rate 0.577 0.345 0.64 0.14 remaining 0.453009
- combined w/ other failures corrected 5 04E"08 0.95308 import 0.064003 0.024714 0.083414 0.007638 0
0.038859 cdf reduc 3.39E-09 1.31E-09 4.41E-09 4.04E-10 2.06E-09 corrected 5.95B-08 Interval 3c llo cdf ¹ ief ratio basic event S-AUX-BLDG-FA uncorrect 8.57E-OS 7.38E-08 1.161247 fail rate 0.577 0
0.5
- 0. 806318 import
- 0. 264195 0
0 S-FODT"1AB/CD-FA
- 0. 193682 0
0 0
0 remaining
- 0. 084247
- 0. 017818
¹ 3.43e-8 removed - overlapping cutsets 16 cdf reduc 1.95E-OS 1.43E-OS 1.31E-09 D-6