interim technical report · on llarch 19, 1982 the, nrc approved eledyne engineering services (tes)...

Robert L. Cloud and Associates, Inc.

Interim Technical Report

DIABLO CANYON UNIT 1INDEPENDENT DESIGN VERI1UCATION PROGRAM

ELECTRICAL ~UIPMEÃZ ANALYSISITR f33

REVISION 0

Docket No. 50-275License No. DPR-76

g/8/83Pro ect te

T Review

"j 8302240083 830+07PDR ADGCK 05000275'DR~~

z/(stPro ect Manager teAppnnred P 105-4-839-033

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)l TELEDYNEENGINEERING SERVICES

PROGRAM MANAGER'S PREFACE

DIABLO CANYON NUCLEAR POWER PLANT - UNIT 1

INDEPENDENT DESIGN VERIFICATION PROGRAM

INTERIM TECHNICAL REPORT

ELECTRICAL EQUIPMENT BY ANALYSIS

This is the thirty-third of a series of, Interim Technical Reports

prepared by the DCNPP-IDVP for the purpose of providing a conclusion of

the program.

This report summarizes the analytical methods and results of the

independent analyses, the concerns, recommendations, and conclusions of

the IDVP with respect to the initial sample for electrical equipment

qualified by analysis. All EOI files initiated for this sample category

have been closed or identified as an error.

As IDVP Program Manager, Teledyne Engineering Services has approved

this ITR-33, including the conclusions and recommendations presented.

The methodology followed by TES in performing this review and evaluation

is described in Appendix D to this report.

ITR Reviewed and Approved

IDVP Program Manager

Teledyne Engineering Services

R. Wray

Assistant Project Manager

ELECTRICAL EQUIPMENT ANALYSIS

Contents

Program llanager's PrefaceList of TablesList of Figures

1.0 IntroductionPurpose and ScopeSummaryBackground

2.0 Independent Design Verification llethods

2.1 Procedures2.2 Licensing Criteria

3.0 Verification Analysis of Electrical Equipment.

3.1 Hot Shutdown 'Remote Control Cabinet

11V

v

1112

3.1.13.1.23.1.33.1.4

3.1.5

3.1.6

blethod of Verification AnalysisResults of Verification AnalysisDesign Analysis blethodsComparison of Verification and DesignAnalysis MethodsComparison of Verification and DesignAnalysis ResultsError and Open Item Reports

8ll1414

17

3.2 blain Annunciator Cabinet 18

3.2.13.2.23.2.33.2.4

3.2.5

llethods of Verification AnalysisResults of Verification AnalysisDesign Analysis I'lethodsComparison of Verification and DesignAnalysis blethodsError and Open Item Reports

21232426

27

4.0 Evaluation of Electrical Equipment Analysis

4.1 Interpretation4.2 Recommendations

28

2828

5.0 Conclusion

6.0 References

29

30

7.0 Appendix A — EOI Status-Electrical Equipment AnalysisAppendix B — Key Term DefinitionsAppendix C — Hosgri Response Spectra Considered in

IDVP Electrical Equipment AnalysisAppendix D — Program flanager's Assessment

ELECTRICAL EQUIP11ENT ANALYSIS

List of Tables

Comparison of Computed and AllowableLoads and Stresses in the Hot Shut-down Remote Control Cabinet

Comparison of Verification andDesign Analysis Stresses for theHot Shutdown Remote Control Cabinet

Comparison of Computed and AllowableLoads and Stresses in the tiainAnnunciator Cabinet Assembly

12

16

23

ELECTRICAL EQUIPNENT ANALYSIS

Hot Shutdown Remote Control CabinetOverall Configuration

Hot Shutdown Remote Control CabinetSupport

STARDYNE llodel of Instrument Panelsin Hot Shutdown Remote Control Cabinet

Design Analysis Dynamic llodel for HotShutdown Remote Control Cabinet

Main Annunciator Cabinet AssemblyElevation View Looking Nest

Truss Bracing — Plan View and CrossSection

Verification Analysis llodel for NainAnnunciator Cabinet

Design Analysis Computer Model

10

l9

20

22

25

INTRODUCTION

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This interim technical report summarizes theindependent analysis and verification of theinitial sample of electrical equipment qualified byanalysis at Diablo Canyon Nuclear Power Plant Unit 1(DCNPP-1). The electrical equipment sample consistsof the hot shutdown remote control cabinet and themain annunciator cabinet.

This report is one of several interimtechnical reports of the Independent DesignVerification Program (IDVP). Interim technicalreports include references, sample definitions anddescriptions, methodology, a listing of Error andOpen Items, an examination of trends and concerns,and a conclusion (Reference 1). This reportpresents the results of the IDVP electricalequipment analysis'nd serves as a vehicle for NRCreview. It will also be referenced in the Phase IFinal Report.

This report does not include the independentverification of Class IE electrical componentswhich are mounted to the hot shutdown remotecontrol cabinet or main annunciator cabinet. Theseitems were qualified by shake table testing. Theverification of the electrical equipment qualifiedby shake table testing is the subject of a separateinterim technical report (Reference 2) .

Robert L. Cloud and Associates (RLCA) hasperformed verification analyses for the Phase Iinitial sample of electrical'quipment qualified byanalysis. Loads and stresses were calculated andcompared to allowables. Hethodologies andassumptions used in the design analyses werecompared to those in the verification analyses.Allowable criteria were met for the hot shutdown remotecontrol cabinet, and exceeded for the main annunciatorcabinet assembly as a result of an unrealisticdesign analysis assumption. A generic concern hasbeen identified and recommendations for additionalverification have been made.

On September 28, 1981 PGandE reported that adiagram error had -been found in a portion of theseismic qualification of the Diablo Canyon NuclearPower Plant Unit 1. This error resulted in an in-correct application of the seismic floor responsespectra for sections of the annulus of the Unit 1containment building. The error originated whenPGandE transmitted a sketch of Unit 2 to a seismicservice-related contractor. This sketch containedgeometry incorrectly identified as Unit 1 geometry.

As a result of this error, a seismic rever-ification program was established to determine ifthe seismic qualification of the plant was adequatefor the postulated Hosgri 7.5H earthquake. Thisprogram was presented orally to the NRC in ameeting in Bethesda, Maryland on October 9, 1981.

Robert L. Cloud and Associates (RLCA) presenteda preliminary report on the seismic reverificationprogram to the NRC on November 12, 1981 (Reference 3).This report dealt with an examination of the interfacebetween URS/Blume and PGandE.

The NRC commissioners met during the week ofNovember 16, 1981 to review the preliminary reportand the overall situation. On November 19, 1981 anOrder Suspending License CLI-81-30 was issued whichsuspended PGandE's license to load fuel and conductlow power tests up to 5% of rated power at DCNPP-l.This suspending order also specified that an independentdesign verification program be conducted to ensurethat the plant met the licensing criteria.

PGandE retained Robert L. Cloud and Associatesas program manager to develop and implement aprogram that would address the concerns cited inthe order suspending license CLI-81-30. The PhaseI Plan for this program was transmitted to the NRC

staff in December 1981 and discussed on February 3,1982. Phase I deals with PGandE internalactivities and seismic service-related contractorsprior to June 1978.

On llarch 19, 1982 the, NRC approved eledyneEngineering Services (TES) as program manager toreplace Robert L. Cloud and Associates (RLCA).However, RLCA continued to perform the independentreview of seismic, structural and mechanicalaspects of Phase I.The NRC approved the Independent Design Veri-fication Program Phase I Engineering Program Planon April 27, 1982. This plan dictates that asample of piping, equipment, structures and com-ponents be selected for independent analysis. Theresults of these analyses are to be compared to thedesign analyses results. If the acceptancecriteria is exceeded, an Open Item Report is to befiled. Interim technical reports are to be issuedto explain the progress of different segments ofthe technical work.

2. 0 INDEPENDENT DESIGN VERIFICATION METHODS

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The verification analysis used the followingprocedures to analyze the seismic qualification ofthe hot shutdown remote control cabinet and mainannunciator cabinet.

First, the equipment's physical dimensionswere verified in the field. Next, the equipmentwas mathematically modeled to represent theequipment's mass and stiffness characteristics.From this model, natural frequencies weredetermined. Applicable seismic accelerations wereobtained using the natural frequencies togetherwith the appropriate Hosgri response spectra.Forces and moments were calculated for the keyareas. Stresses were determined from the forcesand moments. These computed stresses were comparedto the allowable stresses. Finally, the stressescomputed by the IDVP were compared to the stressesfrom the design analysis.

2.2 LICEHRXHG CRITERIA

The IDVP used the Diablo Canyon Nuclear PowerPlant Unit 1 licensing criteria to analyze the hotshutdown remote control cabinet and the mainannunciator cabinet assembly. This criteria iscontained in the FSAR and the Hosgri Report(References 4 and 5).

Allowable criteria have been taken from the"Steel Construction Handbook, Seventh Edition"(Reference 6). Allowable criteria for concreteexpansion anchors have been taken from PGandEDrawing 054162, Revision 3, "Concrete ExpansionAnchors for Seismic and Static Loading", (Reference7). Loading combinations are also included inAttachment I of the Phase I Engineering ProgramPlan (Reference 8).

3.0 VERIFICATION ANALYSIS OF ELECTRICAL EQUIPliENT

3 1 HQT SHQXDQHH BEHQXE CQhXBQL CMXHEX

The hot shutdown remote control cabinet(called a panel in the Hosgri Report) is located atthe West end of the Unit 1 auxiliary building atelevation 100 feet. The cabinet containsindicators and manual controls for various pumpsand valves in the auxiliary feedwater, borationcontrol, and containment fan cooler systems.

The hot 'shutdown remote control cabinet isdesigned to act as backup to the control roominstrumentation and controls and allows the plantto be brought to a hot shutdown qondition. Theoverall cabinet configuration is shown in Figure l.Figure 2 shows the cabinet base and supportdetails.

The cabinet is made of ll gauge steel. Itsdimensions are approximately 5 feet 10 inches wide,6 feet 6 inches high, and 3 feet deep. The cabinetis oriented such that front-to-back corresponds tothe East-West direction. The front of the cabinethas doors which enclose the 3/16 inch thick steelinstrument panels, one vertical and the otherdiagonal, tilted at 30 degrees up from thehorizontal. Instruments and switches are mountedon both panels (see Figure 1). Steel separationbarriers are welded to the back of the panelsto isolate various instruments.'he rear of thecabinet has doors which provide service access towiring and instrumentation.

A vertical ll gauge sheet metal barrierrunning the full height and depth of the cabinetlaterally separates the interior of the cabinet.This barrier is also shown in Figure 1.

The cabinet is mounted on four steel 4 inchchannels which are welded to a box comprised of 10inch I-beams. This box, in turn, is bolted tosteel plates embedded in the concrete floor.

VerticalInstrument

PanelSteel

Barrier

Gauges &

Switches .

( ypical)

U40 in

78 in

30o

ex~ go

go~

Ooor-

'InstrumentPanel

70 inOblique Front View

Including Cut-Out

,4 inhannel Base

Floor atElevation 100 ft

North

Figure IHot Shutdown Remote Control Cabinet

Overall Configuration

Cl ip

4 inchChannel

3/16 in. oubl eFillet Weld

(Typical ) 2x2xl/4 iAngle Clip

StiffenerPla«5/8 iWelded

Studj (Typical)

Pg

Bol t

Cl i p

I-Beam

Figure 2

Hot Shutdown Remote Control Cabinet Support

3.l.l Hakhai af. Varifizaiiau Baalxaia

Qzcxa1l Gkruakura Gharaaiariakiaa.

After field verifying the dimensions of thehot shutdown remote control cabinet and itssupporting structure, the IDVP developed amathematical model to simulate the equipment's massand stiffness characteristics. Overall cabinetstiffnesses in the horizontal direction werecalculated 'for bending and shear (Reference 9).

These stiffnesses were calculated for areduced cross-section of the cabinet structure.Instead of considering the full 36 inch depth ofthe cabinet in the front-to-back direction,stiffnesses were calculated for the 20 inchsection of cabinet equivalent to the section ofupper cabinet above the diagonal panel (see Figure 1).In addition, the model neglected shear. stiffnesscontribution of the interior steel barrierand any stiffness contribution in this directionfrom the doors.

The stiffnesses were used to develop a singledegree of freedom lump mass model to representoverall cabinet dynamic characteristics. Thecomplete cabinet mass was lumped at the center ofgravity. This model is more flexible than theactual case, and hence, is conservative because itwould yield lower natural frequencies anda larger response. This model was used todetermine the front-to-back horizontal naturalfrequencies.

The IDVP examined the cabinet's configurationand determined that the model of the cabinet in thefront-to-back direction represented the mostflexible direction. Because the natural frequencyin this direction was found to be greater than 33hertz, the IDVP concluded that overall cabinet wasrlgld ~

Hosgri response spectra for 4% damping and,natural frequency results were used to determineseismic accelerations (Reference 5). Torsionalaccelerations of the auxiliary building wereincluded. The value of damping used, however, isirrelevant because the cabinet was rigid (g 33hertz) and zero period accelerations were used. Thespectra considered in the verification analysis arelisted in Appendix C. The following seismicaccelerations were used:

.76 g - Horizontal East-West

.97 g Horizontal North-South

.60 g VerticalThese accelerations were used to calculate the

loads and forces at key areas (see Table 1). Usingthese forces and loads, stresses at key areas werecalculated and. then compared to allowable stresses.

Local Dyuamia. Gharacirriakiaa.

To analyze the cabinet in greater detail, theIDVP created a finite element computer model toexamine the local dynamic characteristics of thecabinet's two instrument panels. Using plateelements, a STARDYNE finite element model wasdeveloped for the two instrument panels. The modeltook into consideration instrument cutouts, majorinstrument weights, and the welded separation,barriers. The configuration of the model is shownin Figure 3. The weights of the instruments werelumped at the node points corresponding to theinstrument locations. The total weight ofinstrumentation included in the model wasapproximately 167 pounds.

VerticalInstrument

Panel

i". DiagonalInstrument'anel

30o

LEGEND

o Grid Points

L Cutout areas withno plate elements

Note: Barriers on'ttte reverse sideare omitted forclarity.

Figure 3

STARDYNE Model of Instrument Panels inHot Shutdown Remote Control Cabinet

10

The 3/16 inch steel instrument panel isintermittently fillet welded to 3 x 2 x 1/4 inchand 2 x 2 x 1/4 inch angles along the perimeter andis tack welded Ko the ll guage interior barrieralong the length of the barrier. The verificationanalysis accounted for these attachment configurationsby using two separate computer models to bound theanalysis. The first model assumed the local paneledges to be simply supported, i.e., no momentresistance at the edges. The second model assumedthe edges to have a fixed boundary condition, i.e.,the edge support does have moment resistancecapability.

Instrument panel frequencies were calculatedfrom the finite element model, and a computerresponse spectrum analysis was performed todetermine the accelerations, loads and stresses.Hosgri response spectra for 48 damping, wereapplied at the edges in the model representing thepanel attachment to the cabinet. Although Hosgriresponse spectra apply to floor mounted equipment,they also apply to these panels because the cab'inetto which they are attached is rigid, (> 33 hertz)in all directions.

Calculated stresses were then compared to theallowables.

3.1.2 Eaao3.4a af 5?arifiaahiau haaly.cia.

The IDVP computed st'resses at the followingkey areas and compared them to the allowablestresses (see Table 1). Both the stresses for thecabinet and those stresses due to local dynamiccharacteristics of the instrument panel arepresented.

Uzi Qbviima Remail Caairal Cahiuai

KRY 6I.RM.Qzaxall Cabiuai

Ccmuuici hllmahle

Cabinet base angle to basechannel bolt stress

Tension*Shear

1<113 psi457 psi

20<000 psi10,000 psi

Cabinet base angle stress 12,288 psi 22,000 psi

Base channel to I-beam weld stress* 1,088 psi 21,000 psi

Angle clip at.?-beam tensile stressAxialBending*Combined

Clip to I-beam bolt stressTensionShear

427 psi (only combined9,984 psi stress compared)

10,411 psi 22,000 psi

2,591 psi 20,000 psi687 psi 10,000 psi

I-beam anchor bolt stressTension*Shear

10,792 psi687 psi

20,000 psi10,000 psi

Cabinet sheet metal stress

Side panel buckling load

10,800 psi 22,000 psi

1 I 260 lb llg 737 lb ~

Local Dyaamia. Ghuraaiariaiiaaaf Xza IGairumaai Paoala.

Maximum combined panel stress 2,546 psi 22,000 psi

*Note: Those stresses marked with an asteriskshow those key areas which are also explicitlyevaluated in the design analysis.

Table 1Comparison of Computed and Allowable Loads and Stresses

in the Hot Shutdown Remote Control Cabinet

12

A comparison of the computed stresses for the keyareas to the allowable stresses shows that thehot shutdown remote control cabinet meets theallowable criteria.

The natural frequency results from thebounding local panel analyses showed the model withsimply supported edges has a first naturalfrequency in the flexible range, and the modelwith fixed edges has a first natural frequencyin the rigid range. These frequencies are givenbelow:

Simply supported edges

Fixed edges

26.5 hertz

42.7 hertz

The local panel was judged to be rigid becausethe actual panel edge boundary conditions arebetween fixed and simply supported edges, and theintermittently fillet welded edges are more similarto the fixed edge boundary condition.

13

The design analysis examined the front to backvibrational frequencies using a lump mass modelwith nine dynamic degrees of freedom (as shown inFigure 4). The side-to-side and vertical naturalfrequencies were determined by inspection to begreater than those for the front-to-back direction,based on the fact that the doors are closed duringnormal. plant operation (Reference 10).

The design analysis calculated loads andstresses using a one mode response spectrumanalysis. Key. areas were examined for shear andoverturning moment loadings. Three key areastresses were reported for the hot shutdown remotecontrol cabinet (shown in Section 3.1.5).3 1 4 CammaXiaaa af 2|:Cifiaaiiat1 at10 Damian.

GDklYRLQ, 8|'K1190k

Both the verification and design analyses ofthe overall cabinet structure considered thecabinet's front-to-back direction to be the mostflexible direction. However, the methodologiesused to represent the front-to-back charateristicsdiffered: while the verification analysis used asingle degree of freedom model based on a reducedcross-section of the cabinet, the design analysisused a lump mass and beam element model with ninelumped masses.

Both the verification and design, analysesfound the lowest natural frequency to be in therigid range. Based on this result, both analysesconcluded that the cabinet natural frequencies inside-to-side and vertical directions were rigid.

The verification analysis also examined thelocal instrument panel.

14

Degree of FreedomCorresponding toFront-to-Back Motion

Beam Element

Fixed PointLumpMasses

Stiffnesses

Figure 4

Design Analysis Dynamic Model ForHot Shutdown Remote Control .Cabinet

15

3.1.5 CgglgMjggkl, gf pgXjfjcigjQD gt15 Qggjgllhualxajs. Baaulha

The IDVP compared the results of theirindependent analysis listed in Section 3.1.2 withthe results of the design analysis as follows:

Cabinet base angle tochannel bolt tensilestress

Verification6QRlyR jQ

1,113 psi

Designhaalzaia

440 psi

Angle clip at I-beambending stress

I-Beam anchor bolttensile stress

9,984 psi

2,482 lbs.

8,.000 psi

520 lbs.

Table 2

Comparison of Verification and Design Analysis Stressesfor the Hot Shutdown Remote Control Cabinet

Both the verification and design analysisstress results are lower than the allowable stresses.Although different methods and assumptions wereused, both analyses produced similar results.

The verification analysis used a single degreeof freedom model using a stiffness calculated froma reduced cross section. The total mass of thecabinet was lumped at the center of gravity'. Thedesign analysis used a more refined model with ninedistributed lump masses.

16

3 1 6 EXAM. RGQ QUENT IKRG1 BRPQLKR

The IDVP issued one EOI report specificallyfor the hot shutdown remote control cabinet. TableA-1 shows the EOI file number, revision, date andstatus.

EOI 1087 reports differences of greater than158 between the independent analysis results andthe design analysis results. This EOI was sub-sequently closed because the IDVP showed allstresses to be'below the allowabl'e stresses.

The IDVP issued three other EOI's not dealingspecifically with the hot shutdown cabinet, but asa result of the RLCA Preliminary Report, "SeismicReverification Program," 'dated November 12, 1981(Reference 3).

EOI 1004 was issued because insufficientdocumentation was available to verify the transmittal ofseismic information across the PGandE and the NSSS(Nuclear Steam Supply System) supplier. The IDVPhas verified this interface through a review ofcorrespondence and an audit of the NSSS supplier.This work is reported in IDVP Interim TechnicalReport Oll, Revision 0 (Reference 11). EOI 1004was resolved as a closed item.

EOI 1006 was issued because insufficientdocumentation was available to verify the interfacebetween PGandE and the groups performing electricalequipment analysis. EOI 1006 was subsequentlyclosed because the IDVP sample analyses verify thetechnical adequacy of the electrical equipmentanalyses without examination of the originalinterface.

EOI 1007 was iss'ued because available records didnot adequately document the transfer of seismicinformation between PGandE and their service-relatedcontractors. EOI 1007 was subsequently closed becausethe IDVP sample analyses verify the technicaladequacy of the electrical equipment analyseswithout examination of the original interface.

17

3.2 MXH MHQHCIETQB CBQIHET

The main annunciator cabinet is an integratedassembly comprised of nine separate cabinets housingvarious electrical components of the main annunciatorsystem (See Figure 5). The cabinet is located onelevation 127 feet in the auxiliary building below thecontrol room in the cable spreading area. The mainannunciator system is used to sound alarms and lightindicator lamps in the main control room to signal theplant operator.

Each of the nine structurally identical cabinets isconstructed of 12 gauge formed members and sheet metal.They have doors in the front and rear which open to allowaccess to the components mounted within. These doors runthe full length and width of each cabinet and closeout-of-plane from the cabinet structure (as opposed toflush with the structure). The components are mounted oninternal racks. Figure 5 shows the general configurationof the cabinet assembly.

The base of the cabinet assembly is welded to steelplates embedded in the floor slab, and has a truss-typebrace tying the t'op of the cabinet assembly to anadjacent concrete wall. The brace is attached to the topof each cabinet through two steel channels which runthe full length of the cabinet assembly. Details of thisbrace are shown in Figure 6.

18

190 in

OClODODOQOQ0aODO

aa

CO

I

CQ

O0Q0

Floor slab atelevation 127 ft-4 in

Figure 5

Main Annunciator Cabinet AssemblyElevation View Looking West

(shown without doors)

19

5 inchChannels

Connections are1/8 inch doublefillet welded

(typical)Truss

Bracing

Weldedgussetplate 14'"

8 I 5 II

~ ~ lTop ofCabinetAssembly

7 I 4)ll 25 in

West

3x3x3/16 AngleNorth

5/8" diameterconcrete anchors

7 II

Detail A-A

Figure 6

Truss BracingPlan View and Cross Section

20

3 2.1 Hashed af 2arifiaaiiaa huahVaia

The IDVP developed a mathematical model of the mainannunciator cabinet assembly after field verifying theconfiguration and selected dimensions of the cabinet andtruss bracing (Reference 12). A single typical cabinetfrom the nine cabinet assembly was examined to determineits individual structural characteristics. The structureof this single cabinet was idealized as solely composedof the four internal 12 gauge formed steel memberslocated at the corners of the cabinet. This simple model.was deemed to be an adequate representation because thefront and back doors do not close in plane with thecabinet structure and hence do not contribute to theshear capabilities in that plane.

Figure 7 shows the verification analysis model forthe main annunciator cabinet.

The stiffness of each of the four 12 gaugeinterior members was determined in the side-to-sidedirection. On the basis of these calculated stiffnesses,the stiffness of the complete cabinet assembly was"thendetermined. The North-South (side-to-side) model wasdeveloped by first calculating the stiffness contributionof the truss bracing in the North-South direction. Thisstiffness was then included in the model with the cabinetstiffness.

The base of the cabinet assembly, which is welded tosteel plates embedded in the floor, was assumed to berigidly attached to the floor slab for all models.

The mass of each cabinet was assumed to be uniformlydistributed along the height of the cabinet. This is aconservative assumption because the actual cabinets havethe heavier components located towards the bottom.

The East-Nest (front-to-back) and vertical directionswere not examined.

21

Spring representiniN-S stiffness ofbracing

Wallconnect'eamwith

uniformlydistributedmass

~.N-S Model

Figure 7

Yerification Analysis Mode1

for Main Annunciator Cabinet

22

The natural frequency of the cabinet assemblyin the North-South directions was calculated as 7.6hertz.

Seismic accelerations were chosen from Hosgriresponse spectra at 4% damping to correspond to the IDVPnatural frequencies. Since there are no response spectraavailable for elevation 127 feet, acceleration values

~ were linearly interpolated between spectra values forelevations 115 feet and 140 feet. The interpolationalso considered the height of the truss bracingattachment point. The spectra used in the verificationanalysis are listed in Appendix C.

An equivalent static method was used to determinethe loads and forces from the 6.38g North-South seismicaccelerations. These loads and forces were then used tocalculate stresses at key areas (see Table 3). Thecalculated stresses were then compared to the allowables.

3.2.2 Baaulha af Varifiaakiau Baa&aia.

The verification analysis computed loads andstresses at the following key areas and comparedthem to the allowables. The results show that thebracing concrete expansion anchor loads and the interiorcabinet member loads for North-South loading exceedallowables (EOI 949).

Key. hraaa.

Harih=Gauih Laaiiaa

all~~ahl~

Truss bracing expansionanchor

2.04 * 1.0

Interior member bending 58.2 ksi 28.0 ksi

* Combined shear/tension interaction

Table 3

Comparison of Computed and AllowableLoads and Stresses in the Hain Annunciator

Cabinet Assembly

23

The desi:gn analysis of the main annunciator cabinetassembly modeled the dynamic characteristics using a lumpmass and beam element computer model (Reference 13). Themodel, shown in Figure 8, only accounted for thefront-to-back (East-Nest) motion of the cabinet assembly.The design analysis concluded that the cabinet assemblyis rigid in the side-to-side direction because the doorswere assumed to provide a substantial stiffnesscontribution in that direction when they were closed.

The model lumped the structural properties of thecolumns of adjacent cabinets together into a series ofindividual beam elements. A total of 30 lump masses arecontained in the computer model. The mass of eachcabinet was equally distributed to three lump masseslocated on each of the series of beams (see Figure 8 forthe design analysis model representation). These lumpmasses are located at the center line of the horizontalreinforcing members. The model was set up such thatdegrees of freedom for the lump masses allowed forfront-to-back motion only.

For boundary conditions, the design analysis assumedthat the bottom of the cabinet assembly is fixed to thefloor slab. At the top of the cabinet assembly, the modelwas laterally restrained at the brace attachment points.

Natural frequencies in the rigid range werecalculated from this lump mass model. Seismic loadingsfor the assembly location at elevation 127 feet wereobtained by interpolating between elevation 115 feet and140 feet spectra. The seismic inputs used in the designanalysis were compared to the Hosgri spectra. EOI 1008was issued to note that the design analysis seismicinputs were taken from preliminary spectra. Theseseismic loadings were used to calculate stresses at fourkey locations. These stresses were then compared to theallowable stresses.

24

Lateralsupport

provided byhorizontal

steel bracket.

Typical:interiorcolumn

Typical beam

Typicalend column

I

Y

I

I

I /

I II(

Typicaldynamic

degree offreedom

Typicalinter-cabinet

coupling member

Outline ofcabinet assembly

Figure 8

Design Analysis Computer Model

3.2.4 Cumpariaaa uf. Varifiaaiiaa aai Qaaiau.haa3.ymir Hakh~ia.

The difference between the design analysis and theverification analysis is that the design analysis assumedthat the cabinet assembly was rigid in the side-to-side(North-South) direction. Thus, the design analysis didnot account for the effects of the amplified structuralresponse in the side-to-side (North-South) direction.

The design analysis did not report loads andstresses in the upper truss bracing. The verificationanalysis of the connection between the truss bracing andthe wall showed that when the structural response in theside-to-side (North-South) direction was accounted for,the expansion anchor bolt loads exceeded the allowable(EOI 949) .

26

The IDVP issued two EOI reports for the mainannunciator cabinet assembly. Appendix A shows the EOIfile number, revision, date and status.

EOI 949 was issued because the loads (determined bythe IDVP) on the concrete expansion anchors securing thetruss bracing to the wall exceeded the allowable. Inaddition, the design analysis assumed that the cabinetwas rigid in the side-to-side direction. The concreteexpansion anchor loads exceeded allowables because thedesign analysis did not examine the side-to-side motionbased on this rigidity assumption. The IDVP found theside-to-side natural frequency of the structure to be inthe flexible range.

PGandE is modifying the main annunciator cabinetassembly to make the cabinet assembly rigid in the side-to-side direction. EOI 949 is described as an ErrorClass A or B pending IDVP verification of themodif ication.

EOI 1008 was issued because the PGandE qualifyinganalysis for the main annunciator cabinet assemblyreferenced preliminary Hosgri response spectra (dated4/4/77). Results of the verification analysis indicatethat the use of preliminary spectra did not causeallowables to be exceeded. EOI 1008 was classified as aClass C Error.

27

4.0 EVALUATION OF ELECTRICAL EQUIPIIENT ANALYSIS

4.1 IHXEBPBEXMXQE

The IDVP performed analyses for two samples ofelectrical equipment qualified by analysis: the hotshutdown cabinet and the main annunciator cabinetassembly. The verification analysis found that theallowable criteria were met for the hot shutdown remotecontrol cabinet and exceeded in the main annunciatorcabinet assembly.

Three EOIs have been issued as a result of thecomparison between the verification and design analysesmethods and results (EOIs 949, 1087 and 1008). Twoconcerns have been noted:

o The assumption in the design analysis that themain annunciator cabinet is rigid in the North-South direction was shown to be incorrect.This leads to a concern with rigidityassumptions (EOI 949) .

o Spectra not contained in the Hosgri report wereused in the analysis (EOI 1008).

4.2 BECQHHQHMTIQHG

The following recommendations address the concernsdescribed in the interpretation. section:

o Review the adequacy of all assumptions used in thefrequency calculations for all electrical equipment

~ qualified by analysis. These include instrument AC

panel, instrument panels PIA, B and C and localinstrument panels. This additional verification is alsodescribed in ITR Ol, Revision 1 (Reference 14).

o Review all seismic inputs as already set forth inthe DCP corrective action program.

28

5.0 CONCL'USION

The verification analysis found that the hotshutdown remote control- cabinet meets the allowablecriteria.

Review and comparison of the design analysisand the verification analysis indicates that the designanalysis used an unrealistic assumption for the mainannunciator cabinet rigidity. The results of theverification analysis show that, as a result ofpostulated Hosgri seismic loading, allowable criteriahave been exceeded for the main annunciator cabinetassembly (EOI 949). Additional verification has beenrecommended to address this concern.

29

6.0 REFERENCES

TibiaDCNPP Independent Design Verifi-cation Program, Programtlanagement Plan, Phase I, Re-vision 1, July 6, 1982

Interim Technical Report,Independent Design VerificationProgram, Shake Table Testing,Revision 0.

RLCA Preliminary Report — SeismicReverification Program, November 12,1981.

BLCh Eilr. He

P105-4-810-023

P105-4-839-004

PGandE Final Safety Analysis Report,USAEC Docket Nos. 50-275 and 50-273.

PGandE Report: "'Seismic Evaluationfor Postulated 7.5H Hosgri Earth-quake," USNRC Docket Nos. 50-275and 50-323.

AISC, "llanual of Steel Constructioni"7th Edition, 1973.

PGandE Engineering Standard, DrawingNo. 054162, Revision 3, "ConcreteExpansion Anchors for Seismic andStatic Loading."

DCNPP Independent and Design Veri-fication Program, Program Procedure,Phase I, Engineering Program Plan,Revision 0, [larch 31, 1982.

RLCA Verification Analysis of theHot Shutdown Remote Control Panel,Revision 2.

P105-4-200-005

P105-4-200-001

P105-4-455-054

P105-4-570-004

30

PGandE Seismic Qualification ofHot Shutdown Panel, El..100,Auxiliary Building, Diablo CanyonNuclear Power Plant.

IDVP Interim Technical Report,Pacific Gas 6 Electric — WestinghouseSeismic Interface Review, ITR «ll,ll/2/82.RLCA Verification Analysis — t1ainAnnunciator Cabinet, Revision 3.

Dynamic Seismic Analysis of NainAnnunciator Cabinet Structure,Auxiliary Building, Diablo CanyonPower Plant, June 1977.

IDVP Interim Technical Report,Additional Verification and Addi-tional Sampling, ITR 01, Revision l.IDVP, Program Procedure, Preparationof Open Item Reports, Error Reports,Program Resolution Reports, and IDVPCompletion Reports, DCNPP-IDVP-PP-003,Revision 1.

BIGS Eilr. Ha

P105-4-437-004

P105-4-570-001

P105-4-447-010

31

Robert L. Cloud and Associates, Inc

Appendix A

'EOI Status — Electrical Equipment Analysis

(2 pages)

Appendix A

Error and Open Item Reports

EOIFile No. Subject Rev. Date By Type

ActionRequired

PhysicalViod.

. 949

1004

Main Annunciator Cabinet- 0Stresses Exceed Allowables'

2

Documentation of FormalTransmittals of spectra toWestinghouse (issued as aresult of the RLCA Pre-lizmnary Report, ll/12/82)

1/20/824/21/829/3/82

2/6/823/22/824/17/825/24/826/9/82

6/22/826/22/82

RLCARIZA

TESTES

RLCATESTES

OIRPER/AorB

OIR

OIRPPRR/DEV

PRR/OIP.OIR

PPRR/CIPRR/CI

CR

RLCATES

PGandERIZA

TESTES

None

Yes

1006

1007

Documentation for Elec-trical Equipln nt Analysis(issued as a result ofthe Preliminary Report,11/12/82)

Docunentation for Elec-trical Equipment Analysis(issued as a result ofthe Prelinrinary Report,11/12/82)

'012

2/6/823/9/82

4/21/82

2/6/823/9/82

4/21/82

OIRPPRR/CI

CR

OIRPPRR/CI

CR-

RLCATES

None

1008 Main Annunciator Cabinet-PreliIIILnary Spectra

0 '2/9/821 3/18/822 — 6/8/823 10/18/82

RLCARLCA

TESTES

OIRPER/CER/C

RLCA'KS

PGandE. None

STATUS: Status 1s indicated by the type of classification of latest report received by PGandE:

OIR - Open Item Report ER - Error Report A - Class A ErrorPPRR - Potential Program Resolut1on Report CR - Completion Report B - Class D ErrorPRR - Program Resolution Report CI «Closed Item C - Class C ErrorPER - Potential Error Report DEV - Deviation D - Class D Error

OIP - Open Item w1th future action by PGandE

PHYSICAL ROD: Physical modification requ1red to resolve the issue. Blank entry indicates thatmodification has not been determined.

Appendix A

Error and Open Item Reports

EOIFile No. Subject Rev. Date By Type

ActionRequired

Physicall'od.

1087 Hot Shutdawn Remote Con-trol Panel 15/ Difference

01234

5/14/82 RLCA5/26 /82 RLCA5/28/82 RLCA6/23/82 TES6/23/82 TES

OIRPPRR/CIPPRR/CI

PRR/CICR

RLCATESTESTES

None

STATUS: Status is indicated by the type of classification of latest report received by PGandE:

OIR - Open Item Report ER - Error Report A - Class A Error

PPRR - Potential Program Resolution Report CR - Completion Report 0 - Class 0 Error

PRR - Program Resolution Report ,CI - Closed Item C - Class C Error

PER - Potential Error Report DEV - Deviation D - Class 0 Error

OIP - Open Item with future action by PGandE

PIIYSICAL NOD: Physical modification required to resolve the issue. 0lank entry indicates thatmodification has not been determined.


Appendix 8

Key Term Definitions

(6 pages)

KEY TER11S AND DEFINITIONS USED .INTHE ELECTRICAL EQUIP[1ENT ANALYSIS REPORT

(The definitions in this glossary establish'the meaningsof words in the context of their use in this document.These meanings in no way replace the specific legal andlicensing definitions.)

Acceptance Criteria— The comparison between the design analysis and

the independent analysis where the results mustagree within l5% and be below allowable. Fail-ure to meet this acceptance criteria results inthe issuance of an Open Item.

Allowable Criteria— llaximum stress or load provided by the licensing

criteria.Closed Item

— A form of program resolution of an Open Itemwhich indicates that the reported aspect isneither an Error nor a Deviation. No furtherIDVP action is required (from Reference l5).

Completion Report— Used to indicate that the IDVP effort related

to the Open Item identified by the File Numberis complete. It references either a ProgramResolution Report which recategorized the itemas a Closed Item or a PGandE document whichstates that no physical modification is to beapplied in the case of a Deviation or a ClassD Error (from Reference 15).

DCNPP-l

Diablo Canyon Nuclear Power Plant Unit lDesign Codes

— Accepted industry standards for design (ex. AISC,AISIg ANSI'S('1Eg AK'/Ag IEEE) ~

EOI

— Error and Open.-Item Report

Error Report— An Error is a form of program resolution of an

Open Item indicating an incorrect result that hasbeen verified as such. It may be due to a math-ematical mistake, use of wrong analyticalmethod, omission of data or use of inapplicabledata.

~ Each Error shall .be classified as one of thefollowing:

o Class A: An Error is considered Class A if designcriteria or operating limits of safety relatedequipment are exceeded and, as a result, physicalmodifications or changes in operating proceduresare required. Any PGandE corrective action issubject to verification by the IDVP.

o Class B: An Error is considered Class B if designcriteria or operating limits of safety relatedequipment are exceeded, but are resolvable bymeans of more realistic calculations or retesting.Any PGandE corrective action is subject to veri-fication by the IDVP.

B-2

o Class C: An Error is considered Class C ifincorrect engineering or installation ofsafety related equipment is found, but nodesign criteria or operating limits are exceeded.No physical modifications are required, but ifany are applied they are subject to verificationby the IDVP.

o Class D: An Error is considered Class D ifsafety related equipment is not affected.No physical modifications are required, butif any are applied, they are subject toverification by the IDVP (From Reference'15).

FSAR

— PGandE's Final Safety Analysis Report

Hosgri Criteria— Licensing criteria referring specifically to

the postulated 7.511 Hosgri earthquake.

Hosgri Report

— A report issued by PGandE that summarizes theirevaluation of the DCNPP-1 for the postulatedHosgri 7.5ll earthquake. Includes seismiclicensing criteria.

Hosgri 7.5ll Earthquake

— Yiaximum earthquake for which the plant isdesigned to remain functional. Same as SafeShutdown Earthquake (SSE).

Interim technical report— Interim technical reports are prepared when a

program participant has completed an aspect oftheir assigned effort in order to provide thecompleted analysis and conclusions. These maybe in support of an, Error, Open Item or Program

B-3

Interim technical report (cont)

Resolution Report or in support of a portionof the work which verifies acceptability.Since such a report is a conclusion of theprogram, it is subject to the review of theProgram Manager. The report will be trans-mitted simultaneously to PGandE and to the NRC(From Reference 1).

Licensing Criteria— Contained in PGandE Licensing Documents,

includes allowable criteria (See HosgriReport definition).

NRC

— Nuclear Regulatory Commission

NRC Order Suspending License CLI-81-30L

— The order dated November 19, 1981 that sus-pended the license to load fuel and operateDCNPP-1 at power levels'up to 5% of full powerand specified the programs that must be completedprior to lifting of the suspension.

Open Item— A concern that has not been verified, fully

understood and its significance assessed. 'heforms of program resolution of an Open Item arerecategorized as an Error, Deviation, or a ClosedItem. (From Reference 15).

PGandE

— Pacific Gas and Electric Company

Phase I Program

— Review performed by RLCA< RFR, and TES restrictedto verifying work performed prior to June 1978related to the Hosgri re-evaluation designactivities of PGandE and their seismic service-relatedcontractors.

B-4

Potential Program Resolution Reportand Potential Error Report

— Forms used for communication. within IDVP.

Program Resolution Report

— Used to indicate that the specific item is nolonger active in the IDVP. It indicates whetherthe resolution is a Closed Item, a Deviation, orthat responsibility for an Open Item has beentransferred to the PGandE Technical Program.Further IDVP action is required upon completionof the associated PGandE Technical Program Taskif the IDVP transfers an Open Item to PGandE orif physical modifications are applied wi'th respectto a deviation (Reference 15).

Response

— The motion resulting from an excitation of adevice or system under specified conditions.

Response Spectra— Graph showing relationship between acceleration

and frequency. Used in seismic analysis.

RLCA

— Robert L. Cloud and Associates, Inc.

Sample

— Initial Sample stipulated in Phase I Progra'mof equipment, components, and buildings to bedesign verified by independent analysis.

B-5

Sampling Approach

— llethod used by the IDVP to determine the initialsample (buildings, piping, equipment and compon-ents) for analysis and to provide for sampleexpansion when required.

SSE

— Safe Shutdown Earthquake: l1aximum earthquakefor which the plant is designed to remainfunctional (Hosgri 7.5ll).

Seismic

— Refers to earthquake data.

Single Degree of Freedom llodel

— Simplified mathematical representation of astructure.

TES

— Teledyne Engineering Services

Verification Program

— Undertaken by the IDVP to evaluate DiabloCanyon Nuclear Power Plant for compliancewith the licensing criteria.

B-6


Appen~ C

Hosgri Response Spectra Considered

in IDVP Electrical Equipment Analysis"

(1 page).

APPENDIX C

HOSGRI RESPONSE SPECTRA CONSIDERED IN THEIDUP ELECTRICAL EQUIPMENT ANALYSIS

4 114' 119~ 4 123' 1274 132~ 4 137' 141~ 4 145

Hgk Gggiggwg BCUlotg ggDQXoj, gybe,Dgf

Horizontal: Figures *

Vertical: Figures *

UQj.Q gggggcj,gggg gag).QRK

Horizontal: Figures *

4-150

4-112, 4-113, 4-117, 4-118,4-121, 4-122, 4-125~ 4-126.

*Figure numbers correspond to those from the HosgriReport, (Reference 5).

Robert L. Cloud and Associates, Inc

Appends D

Program Manager ' Assessment

(1 page)

<s-TELEDYNEENGINEERINQ SERVICES

APPENDIX D

PROGRAM MANAGERS ASSESSMENT

As IDVP Program Manager, TELEDYNE ENGINEERING SERVICES (TES) has

established a Review and Evaluation Team, headed by a qualified team

leader, as described in Section 7.4 (C) of the Phase I Program Manage-

ment Plan (Rev. 1). The assigned team leader for the area, Electrical

Equipment, included in the Interim Technical Report, has personally dis-

cussed the procedures, approach, field trip files, analyses, calculations,

etc. with RLCA personnel. In addition, the TES Team Leader has reviewed

the Open Item Files pertaining to this area of responsibility and, in

particular, those files for which RLCA has issued Potential Program Res-

olution Reports or Potential Error Reports, and on the basis of this

evaluation, has recommended appropriate resolution to the IDVP Program

Manager.

I

Based on this review and evaluation process to date, the Team Leader,

along with the TES Program Management Team, has studied and has concurred

with the Interpretation and Recommendations outlined in Sections 4.1 and

4.2 of this report.

0-1

p

C. g <t