ML20137C070
| ML20137C070 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 03/18/1997 |
| From: | Diane Jackson NRC (Affiliation Not Assigned) |
| To: | NRC (Affiliation Not Assigned) |
| References | |
| NUDOCS 9703240146 | |
| Download: ML20137C070 (35) | |
Text
a March 18,1997
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APPLICANT: -Westinghouse Electric Corporation l
FACILITY:
AP600
SUBJECT:
SUWiARY OF MEETING TO DISCUSS WESTINGHOUSE AP600 STRUCTURAL i
MODULES i
The subject meeting was held at the Westinghouse Electric Corporation (West-inghouse) office in Rockville, Maryland, on January 14 through.16,1997. The purposes of the meeting were to discuss Westinghouse standard safety analysis j
report (SSAR) Sections 3.8.3 and 3.8.4 related to the design and analysis of structural modules for AP600, review the structural design calculations, and
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resolve the remaining draft safety evaluation report (DSER) Open Items and i
j technical questions from the May 22 and 23,1996, meeting. is a list of meeting participants. Attachment'2 is the meeting agenda, list of open items proposed for discussion, and the list of technical questions from j
the May 22 and 23, 1996, meeting.
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Discussions were primarily focused on resolving individual DSER open items and i
previously raised technical questions. During the Nuclear Regulatory Commis-sion review of the structural design calculations, questions were posed to Westinghouse as they came up. Westinghouse's responses were considered in developing an overall evaluation of the quality and completeness of the design calculations.
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At the end of the meeting, the results were summarized by updating the status of the DSER open items list and reviewing the disposition of the technical l
questions from the May 1996 meeting. Attachment 3 is the status of open items
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as a result of the discussions. Attachment 4-is a summary of meeting issues.
' is the draft SSAR markups and handouts provided by Westinghouse.
j original signed by:
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Diane T. Jackson, Project Manager Standardization Project Directorate Division of Reactor Program Management Office of Nuclear Reactor Regulation I
Docket No.52-003 i
Attachments: As stated j
cc w/ attachments:
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i DISTRIBUTION:
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l NAME DTJackson:sg 7 GBagchi TRQuay 74>
DATE 03/lf/97 0
03/17/97 03/19/97 9703240146 970318 PDR ADOCK 05200003 A
I Westinghouse Electric Corporation Docket No.52-003 l
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cc: Mr. Nicholas J. Liparulo, Manager Mr. Frank A. Ross i
Nuclear Safety and Regulatory Analysis U.S. Department of Energy, NE-42 Nuclear and Advanced Technology Division Office of LWR Safety and Technology i
Westinghouse Electric Corporation 19901 Ger.nantown Road P.O. Box 355 Germantown, MD 20874 i
Pittsburgh, PA 15230 Mr. Ronald Simard, Director Mr. B. A. McIntyre Advanced Reactor Program Advanced Plant Safety & Licensing Nuclear Energy Institute Westinghouse Electric Corporation 1776 Eye Street, N.W.
I Energy Systems Business Unit Suite 300 Box 355 Washington, DC 20006-3706 Pittsburgh, PA 15230 Ms.,Lynn Connor Ms. Cindy L. Haag Doc-Search Associates Advanced Plant Safety & Licensing Post Office Box 34 i
Westinghouse Electric Corporation Cabin John, MD 20818 i
Energy Systems Business Unit Box 355 Mr. James E. Quinn, Projects Manager Pittsburgh, PA 15230 LMR and SBWR Programs GE Nuclear Energy Mr. M. D. Beaumont 175 Curtner Avenue, M/C 165 Nuclear and Advanced Technology Division San Jose, CA 95125 Westinghouse Electric Corporation One Montrose Metro Mr. Robert H. Buchholz 11921 Rockville Pike GE Nuclear Energy.
Suite 350 175 Curtner Avenue, MC-781 Rockville, MD 20852 San Jose, CA 95125 Mr. Sterling Franks Barton Z. Cowan, Esq.
U.S. Department of Energy Eckert Seamans Cherin & Mellott NE-50 600 Grant Street 42nd Floor 19901 Germantown Road Pittsburgh, PA 15219 Germantown, MD 20874 Mr. Ed Rodwell, Manager Mr. S. M. Modro PWR Design Certification Nuclear Systems Analysis Technologies Electric Power Research Institute Lockheed Idaho Technologies Company 3412 Hillview Avenue Post Office Box 1625 Palo Alto, CA 94303 Idaho Falls, ID 83415 Mr. Joseph Braverman Mr. Charles Thompson, Nuclear Engineer Brookhaven National Laboratory AP600 Certification Building 475 NE-50 Upton, NY 11973-5000
'19901 Germantown Road Germantown, MD 20874
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AP600 STRUCTURAL MODULE DESIGN NRC/ WESTINGHOUSE MEETING JANUARY 14 THROUGH 16, 1997 4
j LIST OF MEETING PARTICIPANTS fi8 tie ORGANIZATION GOUTAM BAGCHI
- NRC/DE/ECGB THOMAS CHENG NRC/DE/ECGB DINO SCALETTI NRC/DRPM/PDST JOSEPH BRAVERMAN BNL/NRC CONSULTANT RICHARD MORANTE BNL/NRC CONSULTANT DONALD LINDGREN WESTINGHOUSE RA0 MANDAVA WESTINGHOUSE RICHARD ORR WESTINGHOUSE BRIAN MCINTYRE
- WESTINGHOUSE KARL GROSS BECHTEL/ WESTINGHOUSE CONSULTANT DONALD CHUNG
- SCIENTECH, INC.
BRUCE PUSHECK EPRI
- PART TIME
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AP600 STRUCTURAL MODULES NRC / WESTINGHOUSE MEETING AGENDA i
JANUARY 14 - 16, 1997 i
1 4
i INTRODUCTION R.MANDAVA T.CHENG i
i PROPOSED REVISIONS TO SSAR SUBSECTIONS 3.8.3 AND 3.8.4 i
SUMMARY
REPORTS l
CONTAINMENT INTERNAL STRUCTURES HYDRODYNAMIC ANALYSES 4
AUXILIARY BUILDING STRUCTURES I
OTHER TOPICS CONTAINMENT AIR BAFFLE ELECTRICAL RACEWAY AND DUCT DESIGN CRITERIA l
TURBINE BUILDING BRACING l
'i DSER OPEN ITEMS EXIT MEETING i
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SUMMARY
REPORTS AND CRITICAL SECTIONS 4
Location Document numbers j
Auxiliary Building Summary Report 1200 S3R-001 Floor at elevation 135' 3" - Areas 1 & 2 1250 CR-125, Rev. O I[.
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Finned Door 1252 CCC 001, Rev.1 1252-CCC-004, Rev. 0 Spent fuel pool liner details (including 1200 SUC-101 M20/M21) 1210-SU 562 thru 565,901.952 958 Containment laternal Structures Summary Report Structural module design criteria GW SUP-001, Rev 1 GW-SUP 003, Rev 1 GW-SUP-005, Rev 0 IRWST analyses MT03-S3C-012, Rev. O ADS MT03 S3C-018, Rev 0 Pressure i
MT03 S3C-019, Rev 0 Thermal MT03-S3C-020, Rev 0 Seismic GW-SUP-006, Rev 0 Thermal inputs West wall of the refueling cavity, it will 1100 SUC-101 include the connections to the IRWST II00 SU-901906 outer wall, the operating noor (elevation ll20-SU-001 135') and the base connection to the 1130-SU-001 basemat.
I150 SMC 101 South wall of steam generator cav.ty i
ll50 SS-004 1150-SS-901- % 3 North East wall of IRWST including PRHRHX.
IRWST wall (steel wall adjacent to MT03 S2R 022, Rev. I containment vessel) 1 Column in the containment internal ll50 SMC-101, Rev. O structures 8
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JAN 8 '97 11:31 FROM AP600 DESIGN CERT TO NRC PAGE.003 DSER OPEN ITEMS FOLLOWING STRUCTURAL MEETINGS / AUDITS (December,1996)
Seismic Analyses 628 Shallow soit site / site specific analyses l
649 Effect of NI on seismic input to adjacent buildings 662 Classification of turbine building 664 Seismic margin of turbine building 668 Time history versus response spectrum analyses 670 COL applicant site specific analyses l
672 Equivalent static analyses for subsystems i
1885 COL applicant site specific analyses Nuclear Island Basemat 766 Validation package for Initec computer codes 767 Simplified analyses / consistency of analyses 768 Analyses for construction loads 1
769 Soil spring variability 772 Waterproofing system Shield Building Roof 750 Shield building roof design calculations 751 Post construction testing of pcs tank 3057 Thermal cracking assumptions Containneemt vessel 678 Containment vessel design loads 681 Containment vessel - design of large penetrations Amulliary Building 745 Combination of full live load with SSE 698,706,708,1888,2515 Containment vessel fragility l
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- TOTAL PAGE.003 **
JAN 8 '97 11:31 FROM AP600 DESIGN CERT TO NRC PAGE.002 i
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DSER OPEN ITEMS FOR NRC REVIEW j
DURING STRUCTURAL MEETINGS / AUDITS j
JANUARY 14-16, 1997 3
Containement Internal Structuns, Structurai Modules, IRWST Analyses, Air baffle l
623 Damping for cable trays 710 Module connection details l
711 CIS lift off l
716 ACI / AISC for module design j
717 Module construction process 718 Concrete placement stresses in steel plates 719 Combination of ADS and SSE l
720 Module seismic analysis methods
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722 Monolithic properties in global seismic analysis j
724 Composite behavior i
725 Seismic modelling l
729 Module composite behavior study i
730 Module connection details i
731 Design Summary Report for containment internal structures 732 Structural audit of containment internal structures 740 Description and design details for modules in auxiliary building.
j 754 Description and design details for spent fuel pool, and fuel transfer canal 755 Design Summary Report l
757 Design criteria for modules in auxilary building 758 Modular construction in auxiliary building l
791 HVAC ductwork and electrical raceways 2347 Design process for module design i
2349 Analysis of typical 30" wall 2348 Hydrodynamic analyses 3247 RAI 230.98 Design of structural modules i
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1 Fron: Sumary of fleeting to Discuss llestinghouse AP600 Structural Modules, flay 22 - 23, 1996, Issued July 1, 1996 Design Criteria for Structural Modules Inside/Outside AP600 Containment 1
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Staff's Comments and Ouestions on Revision 7 of SSAR Sections 3.8.3 and 3.8.4 l.
Page 3.8-16 of the SSAR refers to using welded studs or similar embedded i
steel elements attached to the steel form modules (liners) where surface attachments transfer loads into the concrete. Are any of the attachments Seismic Category I (safety related)?
If so, then these liners should be described in the SSAR.
j 2.
Page 3.8-18, SSAR Subsection 3.8.3.1.3 lacks description and details on connections between structural modules. Also, no figure identifies the j
location of the attachments of the individual modules that make up the j
assembled M1 module.
3.
Page,3.8-19, SSAR Subsection 3.8.3.1.5, what types of equipment are supported on the platforms? Are any loads transmitted to the module walls?
4.
Page 3.8-19, SSAR Subsection 3.8.3.2 (also 3.8.4.2 and 3.8.3.6.2) welding and weld inspection are discussed. Does the 10 percent MT/PT for partial.
penetration welds apply to all steel structures designed to AISC - N690 i
or only to the concrete-filled steel modules? Are weld efficiency j
factors from N690 used in the design calculations?
g, 5.
Page 3.8-20, SSAR Subsection 3.8.3.3.1 - Loads and Load Combinations.
Explain why the extreme flood loads, designated "N" in the SSAR, does not i
appear in the Load Combination Tables. ACI-349 addresses this load, j
indicating it should be substituted for "W," in Load Combination 5.
i 6.
ACI-349 identifies load "F" in its load combinations. The SSAR load combination tables also belude "F" However, there is no definition or l
even mention of "F" tn the SSAR text. Why?
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Page 3.8-21, SSAR Subsection 3.8.3.3.1 for ADS it is stated that "long j
term heating of the tank is bounded by the des},gn for ADS, load." Is this the ~ worst thermal condition, or do other thermal transients (mentioned in Subsection 3.8.3.4.3) for design basis accidents control the design?
Discuss the results of the unidimensional heat flow analyses identified j
in Subsection 3.8.3.4.3.
8.
Page 3.8-21, SSAR Subsection 3.8.3.3.1 for ADS states that the IRWST is designed for an internal pressure of 5 psi occurring at anytime up to 24 i
hours after initiation of the event.
Is it 5 psi plus the hydrostatic head of water in the tank? Is the 5 psi the actual peak pressure, an equivalent static pressure, or a conservative upper bound design value for ADS. Why is the 5 psi applicable only to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />?
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Page 3.8-21, SSAR Subsection 3.8.3.3.2 - Concrete Placement Loads. How j
was the face plate stress of 13,000 psi calculated for the concrete i
placement load? Is this stress fully relieved when the concrete hardens l
or is there a residual stress and deflection after the concrete hardens?
l Explain why any residual stress does not affect the response under operating loads. Expand on the discussion in SSAR.
10.
Page 3.8-22, SSAR Subsection 3.8.3.4 - Analysis Procedures. The descrip-tion about the use of " absolute" or " relative magnitudes of stiffness" l
depending on the type of load is not clear.
- 11. SSAR Subsection 3.8.3.4 describet four cases for calculating the wall stiffnesses. The use of a particular case for each analysis needs to be j
reviewed. The description in the SSAR is. difficult'to follow and j
requires a more complete justification.
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12.
Page 3.8-26, SSAR Subsection 3.8.3.4.2 only describes the analyses for l
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Page'3.8-26, SSAR Subsection 3.8.3.4.2.1.
Modeling and analysis used for j
the fluid-structure 3D 15 degree sector need to be described more fully.
1 For example, was fluid compressibility referred to in this section i
actually used and'what properties were used for the wall?
I 14.
Page 3.8-27, SSAR Subsection 3.8.3.4.2.2 - In-Containment Refueling Water i
Storage Tank Analyses. Modeling and analysis used for the 3D model of l
the entire IRWST needs to be described more fully. What is the basis for modeling the steel portion of the IRWST as beam elements. How are the i
isotropic properties for this model detemined? Why are the wall proper-ties for the harmonic analysis different than the wall properties for the i
structural analyses, described in the paragraph that follows it.
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- 15. Page 3.8-28, SSAR Subsection 3.8.3.4.3 - Thermal Analyses.
It is not clear what kind of model was used, what loading was applied, and how p
concrete cracking was c.onsidered.
f 16.
Page 3.8-31, SSAR Subsection 3.8.3.5.3.3 - Design for Out-of-Plane Shear:
Why is it necessary to invoke the AASHTO Bridge Design Specification for out-of-plane shear design criterion?
i What loading is generating an average tensile force of sufficient i
magnitude to necessitate a relaxation from ACI-34g criteria?
i Has the ACI-34g committee considered a revision to incorporate'the i
AASHT0 criterion? If so, what is the status?
If not, why not?
Has all conservatism in the calculation of the tensile force been removed?
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' I What are the alternatives available to meet the ACI-349 design criterion, as applied to out-of-plane shear strength?
Effectively, the NRC is being asked to rule on the appropriateness of the ACI-349 criterion, which was developed by a committee of experts in the field of reinforced concrete design. Can the AASHTO criterion be submitted to the ACI-349 Committee for a judgement on its use for Westinghouse's specific application? ASME has a mecha-nism for review and evaluation of " code cases" submitted by indus-l try.
Does ACI have a similar procedure?
There is a concern that selectively using criteria from different codes undermines the design philosophy embedded in each of the codes. ACI-349 was specifically developed for nuclear power plant structures. How does its design philosophy and underlying conserva-tism compare. to that of the AASHTO Bridge Design Specification?
Considering the amount of time devoted by many individuals to formulate and revise codes such as ACI-349 and AASHTO, it is nal appropriate that a decision be made based on a few days of review of Westinghouse's SSAR revision.
17.
Page 3.8-33, SSAR Subsection 3.8.3.5.3.4.
The use of the Von mises criterion for combined bi-axial normal stresses and in-plane shear stress in the steel face plates is reasonable. A safety factor consistent with the reduction factors (0) in ACI-349 needs to be defined. Once the a
response of the structure has been determined and the ACI-349 design i
criteria have been met for the pseudo reinforced concrete structure, it should be straightforward to determine the corresponding steel face plate normal and shear stresses. Why are these stresses not used in the Von-Mises Criterion to check that the combined stress state in the face plates is below the allowable stress criterion?
18.
Page 3.8-35, SSAR Subsection 3.8.3.5.3.5 - Design of Trusses. This section states that the trusses provide additional strength similar to that provided by stirrups in reinforced concrete.
If credit is taken for the trusses, what criteria govern the design and installation of the trusses?
- 19. Page 3.8-35, SSAR Subsection 3.8.3.5.3.6 - Design of Shear Studs. This section should describe how the loads on the studs will be determined and how they will be designed.
20.
Page 3.8-36, SSAR Subsection 3.8.3.5.4.1 refers to Figure 3.8.3-13.
Note no.1 on this Figure states that the term "b," is determined per Sec-4 tion 3A5.5.2 which no longer exists.
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- 21. Page 3.8-41, SSAR Subsection 3.8.4.1.2 - Auxiliary Building. Details of the modules used in the auxiliary building should be presented since j
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there are some differences in their configuration.
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Page 3.8-46, SSAR Subsection 3.8.4.3.1.4 - Abnormal Loads. Are there any pressures due to pipe break that are applicable to structural modules?
l Explain the pressurization load of 5 psi for P.
23.
Page 3.8-49, SSAR Subsection 3.8.4.5.1 - More information is needed to i
explain what criteria will be used for steel anchorages (e.g. what angle j
will be used instead of the 45 degree cone assumption for concrete capacity).
l 24.
Page 3.8-50, SSAR Subsection 3.8.6.1.1 - Concrete. No reference in this j
section or elsewhere is made to ACI 347R-88 which covers concrete forms.
I 25.
Page 3.8-70, SSAR Table 3.8.4-2 Load Combinations.... Concrete Struc-l tures. Several questions regarding this table need to be discussed (e.g.
i SRV loading and ref. to SRP).
l Status of DSER Onen items
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l 01 3.8.3.1-1 Westinghouse agreed to expand, in a future SSAR revision, i
design details to include connections between "M" modules 4
i and other type of modules. Action Westinahouse i
01 3.8.3.2-1 Westinghouse has incorporated the staff's interin technical position on AISC N690 Standard in SSAR Section 3.8.4.5.1.
j Resolved 01 3.8.3.2-4 Since previous Appendix 3A has been deleted, there is no longer an error to SSAR Section 3.8.3.2.2.1.
Resolved 01 3.8.3.2-5
. Westinghouse agreed to finalize all design criteria for structural modules. Action Westinahouse 01 3.8.3.3 In resolving its concern on this open ites, the staff agreed to re-review Revision 7 of SSAR Sections 3.8.3 and 3.8.4, i
and related documents. Action NRC j
01 3.8.3.3-2 Westinghouse agreed to expand the SSAR description of the methods for considering the hydrostatic pressure due to s
construction in the design. Action Westinahouse
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01 3.8.3.4-3 Westinghouse agreed to provide the analysis and design i
results for the staff review. Action Westinahouse l
01 3.8.3.4-4 Westinghouse agreed to include the wall thickness of modules i
located in the auxiliary building in the future SSAR revi-i sion. Action Westinohouse 4
l 01 3.8.3.4-5 Westinghouse agreed to provide the analysis and design results to demonstrate and confirm the adequacy of the method used for design. Action Westinahouse 3
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STATUS OF DSER OPEN ITEMS IN MODULAR CONSTRUCTION AREA AS A RESULT OF JANUARY 14 THROUGH 16, 1997 MEETING 1
I At-the end of the meeting, the status of DSER open items and several meeting open items being tracked by Westinghouse was reviewed and updated. Several open items, listed in Attachment 2, are unrelated to Structural Modules.
However, were included as part of the meeting agenda and are updated in this status. Westinghouse submitted draft SSAR markups for the response to RAI's related to AP600 structural module by letter dated January 9, 1997. These i
drafts were discussed during the meeting. A discussion of each item follows:
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j New Meetina Onen Item - AP600 Critical Section Details i
Westinghouse was requested to include the critical section details in a formal i
revision to the SSAR. Action W Open Item 3.7.1-1 (0ITS 623) Damoina Ratio for Cable Tray Systems In the markup of SSAR Revision 11, Westinghouse states thet 10 percent damping i
is used for both full loaded and empty cable trays and related supports.
If f
the configuration of cable tray systems is ownstrated to be similar to the configurations tested in SSAR Referer.ce 19, the damping ratio shown in SSAR Figure 3.7.1-13 is used for the seit,mic analysis. Westinghouse's commitment 4
for the use of cable tray damping is consistent with those accepted by the staff in the licensing review of other advanced reactors, such as the Advanced Boiling Water Reactor (ABWR) and meets the guideline recocimended in the j
report, " Recommendations for Revision of Seismic Damping Values in Regulatory l
Guide 1.61," by Brookhaven National Laboratory, and is acceptable to the i
staff. Therefore, Open Item 3.7.1-1 is technically resolved. Westinghouse i
will include the SSAR markup developed at meeting (see Attachment 5) in a formal revisien. Con fi rm-_W i
Ooen Item 3.8.3.1-1 (OITS 710) Connection Details between "M" Modules. and i
Between "M" Modules and Other Tvoe of Modules Westinghouse will include the SSAR markup developed ~at meeting (see Attach-ment 5) in a formal revision. Confirw-W l
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1 Ooen Item 3.8.3.1-2 (0ITS 711) Lift Un Containment Internal Structures Durina An SSE Westinghouse did not provide the design calculation to demonstrate that the containment internal structures will not lift up during a safe shutdown earthquake (SSE). Westinghouse will provide a copy of the applicable calcula-tion to W-Rockville office for staff review. This open item remains unre-solved. Action W Ooen Item 3.0.3.2-5 (OITS 7165 Use of ANSI /AISC N690 Standard and ACI 349 Code for the Desian of Concrete Fi iled "M" Modules This open item was resolved as a result of the January 14 through 17, 1997 l
meeting. The staff accepts the application of ACI-349 to design of the concrete-filled steel modules.
Resolved i
Ooen Item 3.8.3.3-1 (0ITS 717) Inclusion of Entire Construction Process of the Modular Construction in the SSAR This open item was technically resolved as a result of the review of the draft SSAR revision submitted on January 9, 1997, and the January 14 through 17, f
1997, meeting discussion. Westinghouse will include the SSAR draft revision (1/97) in a formal revision. Confirm-W Open Item 3.8.3.3-2 (0ITS 718) Construction-Induced Stress Followina Curina of Concrete This open item was technically resolved as a result of the review of the draft l
SSAR revision submitted on January 9, 1997, and the January 14 through 17, 1997, meeting discussion. Westinghouse will include the SSAR draft revision (1/97) in a formal revision. Confirm-W l
l Open Item 3.8.3.3-3 (OITS 719) Desian of the In-containment Refuelina Water 31praae Tank (IRWST) and Internal Structural Steel Frames Under Combination of Automatic Deoressurization System (ADS) load and SSE There are three concerns addressed in this open item. These three concerns are (a) to consider the combination of the load due to ADS actuation and the l
SSE load in the IRWST design, (b) to include the thermal load in the design of l
the internal structural steel frames, and (c) to include the latest test result (ADS load) in the IRWST design.
From the review of design calculations during January 14 through 17, 1997, meeting, Concerns (a) and (c) were resolved. As for Concern (b), Westinghouse failed to provide design calcula-tions for the staff review during the meeting. Westinghouse will provide a copy of the applicable calculation to W-Rockville office for staff review.
This open item remains unresolved. Action W
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- tem 3.8.3.4-1 (OITS 720) Inconsistency of Usina Analysis Methods in Ca'lcu atina Seismic Forces Committed in the SSAR and Submittal Dated May 17.
1911 In SSAR Revision 2, Westinghouse added Table 3.7.2-14, which delineates the
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various structural models and analysis methods employed in the seismic l-analysis of the nuclear island structures, including the containment internal structures.
In this table, Westinghouse states that, for the generation of design member forces (axial forces, shear forces and bending moments), the containment internal structures were seismically analyzed based on a 3-D fixed-base finite element model and response spectrum analysis method. The l
3-D lumped-mass stick model combined with the response spectrum analysis l
method is used only for determining the SSI scaling factor. This table l
clarifies the inconsistencies noted above. Therefore, Open Item 3.8.3.4-1 is l
technically resolved. Westinghouse will include the SSAR markup developed at j
meeting (see Attachment 5) in a formal revision. Confirm-W Open Item 3.8.3.4-3 (OITS 722) Adeauacy of the Desian based on the Assumotion of a Composite Section Westinghouse must demonstrate the adequacy of the shear stud design crite-ria to ensure that there is composite action, and revise Calculation 1100-500-003. This open item remains unresolved. Action W Open Item 3.8.3.4-4 (OITS 723) Inclusion of Auxiliary Buildina Structural Modules in the Seismic Model Stiffness This open item was technically resolved as a result of the review of the draft SSAR revision submitted on January 9, 1997, and the January 14 through 17, 1997, meeting discussion. Westinghouse will include SSAR markup developed at meeting (see Attachment 5) in a formal revision. Confirm-W.
Ooen Item 3.8.3.4-5 (OITS 724) Use of Local 3-D Solid Model of Module Geometry and Materials for Developina Eauivalent Isotronic Shell Properties The staff accepts the methodology employed by Westinghouse, based on review of tests conducted in Japan on Concrete-Filled Steel Modules.
Resolved Open Item 3.8.3.4-6 (OITS 725) Effect of Concrete Cracks to the Seismic Model of the Containment Internal Structures l
In addressing the effect of concrete cracks to the seismic model of the containment internal structures, Westinghouse states in Revision 7 of the SSAR (Section 3.8.3.4.1.2 and Table 3.8.3-1) that for considering cracks in the concrete fill, the in-plane shear stiffness is calculated based on a 45-degree diagonal concrete compression strut with tensile loads carried by the steel l
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plates. These calculated stiffnesses are considerably lower than the test data described in SSAR References 27 and 28 where the overall stiffness is reduced to 60 to 70 percent of the monolithic stiffness.
If the calculated stiffnesses are used for the boundaries of the in-containment refueling water storage tank, the equivalent shear area of the containment internal structures is reduced by about 30 percent with a corresponding reduction in frequency of i
about 16 percent.
The staff review of this SSAR revision found that the floor response spectra in the containment internal structures are not acceptable for the following two re. sons:
1 (a)
As shown in Revision 7 of SSAR Figures 3.7.1-7 and Table 3.7.2-3, the 1
first dominant frequency of the internal structures in the north-south direction is 13.6 hertz and the corresponding ground spectral accelera-tion is f0.63.
If the first dominant frequency reduced from 113.6 9
hertz to 11.42 hertz (reduced by 16 percent), the corresponding ground spectral acceleration is increased to 10.729 Westinghouse did not consider this ground spectral acceleration increase due to concrete cracks when they calculated the floor response spectra in the contain-ment internal structures.
(b)
In following the guideline of Regulatory Guide 1.122, Westinghouse developed the final floor response spectra by applying the 115 percent peak broadening rule to the enveloped floor response spectra to cover the uncertainties due to material properties of structures and soil, soil-structure interaction techniques, and approximations in the modeling techniques. However, the 115 percent peak broadening cannot cover the uncertainties due to the cracked concrete in the structural modules.
In conclusion, Westinghouse should either regenerate the floor response spectra for the containment internal structures or justify the adequacy of the floor response spectra documented in the SSAR. Action W Qg,en Item 3.8.3.4-10 (0ITS 729) Combined Stress Eauations to Reflect Realistic Action of Walls This open item was technically resolved as a result of the review of the draft SSAR revision submitted on January 9, 1997, and the January 14 through 17, 1997, meeting discussion. Westinghouse will include the SSAR draft revision (1/97) in a formal revision. Confirm-W Ooen Item 3.8.3.4-11 (OITS 730) Connection Details for Concrete-Filled Steel Modules The staff will review design calculations prepared by Westinghouse.
Action-N
. Open Item 3.8.3.4-12 (OITS 731) Desian Summary Reports Westinghouse provided Design Summary Reports for review during the January 14 through 16, 1997, meeting.
Resolved Open Item 3.8.3.4-13 (OITS 732) Desian Calculations of Internal Structures to be Available for the Staff Review During the January 14 through 16, 1997, meeting, the staff found Westing-house's design calculations to be lacking in clarity and completeness.
Westinghou'se was requested to conduct its own design review of these calcula-tions to improve their quality and completeness. Action-W Open Item 3.8,4.1-3 (0ITS 740) Description of Concrete-Filled Steel Modules in Auxiliary Buildina This open item was technically resolved as a result of the review of the draft SSAR revision submitted on January 9, 1997, and the January 14 through 17, 1997, meeting discussion. Westinghouse will include the SSAR markup developed at meeting (see Attachment 5) in a formal revision.
Confirm-W Ooen Item 3.8.4.4-6 (OITS 754) Analysis Procedures and desian Details of Soent i
Fuel Pool. Fuel Transfer Canal and New Fuel Storace Area Westinghouse needs to provide (a) cross references of the definition of design loads including seismic loads, and (b) restrictions for the design of spent fuel pool floor and fuel racks in the SSAR. Westinghouse will (1) add a reference in SSAR Subsection 3.8.4 to the fuel rack design criteria and loads in Section 9.1, (2) revise the description of the spent fuel pool in Subsec-tion 9.1.2.2 paragraph 3, from reinforced concrete to structural module, and (3) provide a reference to Subsection 3.7.2 in Section 9.1.
This open item remains unresolved. Action W Ooen Item 3.8.4.4-7 (OITS 755) Containment Air Baffle Desian Westinghouse will update the design calculations for the containment air baffle to include consideration of air flow fluctuations and the potential for flow-induced vibration / fatigue failure. Action-W Ooen Item 3.8.4.5-1 (OITS 757) - Desian Criteria for Concrete-Filled Steel Modules in Auxiliary Buildina Westinghouse will include the SSAR markup developed at meeting (see Attach-ment 5) in a formal revision. Confirm-W
. 4 Qoen Item 3.8.4.5-2 (0ITS 758) - Quality Control for Modular Construction The staff concluded that this is adequately addressed in Subsection 3.8.3.6 of the SSAR draft revision (1/97). Westinghouse will include the SSAR draft revision (1/97) in a formal revision. Confirm-W Open Item (0ITS 791) - Desian of Cateoory I and Cateoory II Duct Work Based on discussions at the January 14 through 16, 1997, meeting, Westinghouse i
will provide a SSAR mark-up for staff review. Action W Westinahouse Meetina Open Item 2347 - Desian Process for Structural Modules The staff concurs that this is adequately addressed in the SSAR. Closed Wgstinahouse Meetina Open Item 2348 - Analysis of IRWST for ADS Loads Westinghouse will address the remaining open questions from the April 1995 meeting, pertaining to ADS load generation and structural analysis of the
{
IRWST walls. Design calculations will be revised, if necessary. Action W Westinahouse Meetina Ooen Item 2349 - Analysis of 30" Concrete-Filled Steel Module Wall Design calculations for the 30" wall were available for review at the Janu-ary 14 through 16, 1997, meeting.
Closed
'Westinahouse Meetina Open Item 3247 - New Concrete-Filled Steel Module Desian Design calculations for the new module design were available for review at the January 14 through 16, 1997, meeting. Closed t
- l I
4 l
SUttiARY OF MEETING ISSUES 1
References:
)
(1)
Summary of Meeting to Discuss Westinghouse AP600 Structural Modules (May 22 and 23, 1996); Diane T. Jackson, USNRC; dated July 1, 1996.
q (2)
Response to RAI's Related to AP600 Structural Module; B.A. McIntyre, Westinghouse to T.R. Quay, USNRC; dated January 9, 1997.
4 l
Background:
i After the May 22 and 23, 1996, review meeting on AP600 structural modules, a i
number of DSER Open Items remained unresolved.
In addition, a number of technical questions were raised during the meeting, pertaining to the new l
module design and design / analysis procedures presented in Revision 7 of the SSAR. The DSER open item status and the list of technical questions were i
documented in the meeting report (Reference 1).
Also, the standard review plan (SRP) specifies that a structural design review of the final design calculations be conducted. Westinghouse had previously committed to prepare Structural Module Design Reports to provide the details of tho implementation of the design criteria presented in the SSAR.
This review was originally scheduled for September 1996. However, due to delays in completion, the review was postponed until January 1997.
In advance of the meeting, Westinghouse submitted Reference 2, which included a draft revision, dated January 9, 1997, to Sections 3.8.3 and 3.8.4 of the SSAR.
In Reference 2, Westinghouse also identified its proposed responses to each technical question raised at the May 1996 meeting by reference to a specific section of the SSAR draft revision or to a specific design calcula-tion, which would be available for review at the January 1997 meeting.
Meetina Discussions:
A.)
The technical questions identified in Reference 1 were primarily addressed by proposed changes to the SSAR included in the January 1997 draft revision. These are summarized below:
1.
Reference to AASHT0 deleted; ACI-349 referenced for out-of-plane shear loads TECHNICALLY RESOLVED, CONFIRM-W.
2.
Calculation GW-SUP-005 was reviewed to assess the effects of concrete cracking due to ADS thermal loading on the seismic response of the structural modules inside Containment. ACCEPT-ABLE.
3.
" Case 4" module stiffness was deleted.
TECHNICALLY RESOLVED; CONFIRM-M.
( 4.
Calculation GW-SUP-006 was reviewed to assess the effects of ADS thermal gradients on the concrete filled steel module walls of the IRWST. ACCEPTABLE.
5.
Safety related attachments to steel form (liner) modules are adequately addressed in the draft revision. TECHNICALLY RESOLVED; CONFIRM-W.
l 6.
Safety related equipment mounted to steel framing inside contain-ment is adequately covered by SSAR Subsection 3.7.3.
A reference was added in Subsection 3.8.3.5.5.
TECHNICALLY RESOLVED; CON-FIRM-W.
l 7.
Load Definitions and Load Combination Tables were corrected..
TECHNICALLY RESOLVED; CONFIRM-W.
l 8.
A reference to ACI-347R for concrete placement loads was added.
TECHNICALLY RESOLVED; CONFIRM-W.
9, 10.
SSAR Subsection 3.8.3.4 revised and Table 3.8.3-2 added to i
clarify how the various stiffness cases are utilized in the design / analysis process. Draft SSAR was further amended at the meeting, to ensure clarity. TECHNICALLY RESOLVED, CONFIRM-W.
l 11.
Weld inspection to AISC N-690 is specifically identified. TECH-NICALLY RESOLVED; CONFIRM-W.
12.
Description of Structural Steel Module analysis procedure revised to include "shell" elements. TECHNICALLY RESOLVED; CONFIRM-W.
13.
Reference to AISC N-690 was included for design of shear studs.
Also, Calculation 1100-50C-003 was available for review. This issue is included under DSER OPEN ITEM 3.8.3.4-3 (Westinghouse Item No. 722), which is discussed in E. below.
14.1 Method for Evaluation of Stresses in Face Plates was revised to follow ACI 349 methods for stresses in reinforcing steel. Calcu-lation GW-SUP-001 available for review of procedure.
Procedure acceptable.
TECHNICALLY RESOLVED; CONFIRM-W.
14.2 Reference to ASME "3Su" allowable for thermally-induced stresses in steel face plates, in Subsection 3.8.3.5.3.4, was revised to clarify its application. Draft revision needs further clarifica-i tion, to provide justification for accepting thermally induced stresses greater than the yield strength. ACTION W.
I r
l
)
i
- l 15.
SAP 90 results will not be used for any final design calculations, 2
eliminating NRC concern that SAP 90 is not currently accepted for design basis analysis. ACCEPTABLE.
j B.)
Prior to the May 22 and 23, 1996, meeting, BNL prepared a list of j
twenty-five (25) questions on the new concrete-filled steel module design and design / analysis methodology. These are contained in Attach-l ment 2 to Reference 1 and included in Attachment 2 of this meeting summary for reference. These questions were also reviewed at the meeting, to ensure that each has been addressed. Many of these ques-tions are covered in the list of fifteen (15) questions discussed j
.above.
j The disposition of each of these questions is as follows:
1.
Covered by Question 5 in A.
2.
Drawings of Connection Details were reviewed at meeting. West-4 inghouse agreed to include additional connection details in the 9
Draft SSAR Revision. TECHNICALLY RESOLVED, CONFIRM-M.
3.
Primarily piping and valves are supported on platforms. Detailed attachment loads are not a consideration for Design Certifica-tion. ACCEPTABLE.
i 4.
Covered by Question 11 in A.
5.
Covered by Question 7 in A.
{
6.
Covered by Question 7 in A.
s 7.
Covered by Question 4 in A.
8.
Subsection 3.8.3.3.1 revised to clarify use of 5 psi for design of the IRWST. TECHNICALLY RESOLVED; CONFIRM-M.
9.
Subsection 3.8.3.3.2 revised to address the issue of concrete placement loads more completely. TECHNICALLY RESOLVED; CON-FIRM-M.
10.
Covered by Question 9 in A.
11.
Covered by Question 10 in A.
12.
Statement added to SSAR Subsection 3.8.3.4.2 that ADS is less 2
limiting than ADS,.
TECHNICALLY RESOLVED, CONFIRM-M.
13.
Covered by Westinghouse Meeting Open Item 2348. See E below.
T i
i '
{
14.
Covered by Westinghouse Meeting Open Item 2348. See E below.
15.
Covered by Questions 2 and 4 in A.
16.
Covered by Question 1 in A.
17.
Covered by Question 14.1 in A.
18.
Subsection 3.8.3.5.3.5 revised to specify AISC N-690 for design of trusses. TECHNICALLY RESOLVED; CONFIRM-W.
19.
Covered by Question 13 in A.
20.
Figure 3.8.3-13 revised to remove incorrect reference. TECHNI-I CALLY RESOLVED; CONFIRM-M.
t
)
21.
Covered by DSER Open Item 3.8.4.1-3.
See E below.
I 22.
Based on discussions at the January 14 through 16, 1997, meeting, Westinghouse will review the need to postulate loads due to pipe j
break for the structural modules. ACTION W.
1 i
23.
Concrete cone angle is = 35*, but criterion for anchor strength j
is based on anchor spacing. ACCEPTABLE.
l j
24.
Covered by Question 8 in A.
25.
Load Combinations including safety relief valve (SRV) discharge loads are being addressed separately. Westinghouse has submitted a response to NRC for review. This issue is outside the scope of this review area. The staff will discuss it internally for further action.
C.)
The review objective of the structural design calculations was to establish that the design criteria, analysis methods, and loads speci-fied in the SSAR are appropriately utilized in the final design of AP600 Structural Modules. Westinghouse made available for review eighteen (18) design documents and eleven (11) drawings, pertaining to the structural modules inside containment.
Several design documents and drawings pertaining to structural modules in the Auxiliary Building were also made available.
In general, the calculations and analyses presented in the design documents reflect adherence to the commitments stated in the SSAR.
However, the details of implementation were often difficult to follow; several inconsistencies were noted; and several reports did not appear to be final. The reviewers requested Westinghouse to address these i
. _ _ 3 during the review.
In one instam e, the Design of Shear Studs (Doc. No. 110-500-003) was judged to be technically inadequate in its present form.
The reviewers concluded that the ob.lectives of the structural design review was not completely accomplished during this meeting. Additional review will be necessary to complete this effort. Westinghouse was requested to conduct their own revier and improve the quality and completeness of the structural design calculations.
D.)
An additional agenda item for this meeting was the review of the detailed design calculations for the containment air baffle.
Several questions pertaining to the air baffle design were raised during a meeting at Westinghouse in April 1995. At that time, Westinghouse presented a new preliminary design for the containment air baffle. The recently completed design calculations address all but one of the questions posed in April 1995.
Consideration of air flow fluctuations and the potential for flow-induced vibration / fatigue failure has not been addressed to date.
Therefore, the design calculations for the containment air baffle are considered incomplete at this time.
V jc, \\; g 3, y \\
- 3. Defgn of Structurzs, Components, Equipment, and Systems APPENDIX 3A HVAC DUCTS AND DUCT SUPPORTS Except for a short segment containing an isolation damper to the main control room, and the containment vessel penetration, the AP600 plant has no seismic Category I HVAC ducts.
Therefore, this appendix provides the design criteria primarily for seismic Category II HVAC ducts and their supports.
The structural components of a typical HVAC duct system include the sheet metal ducts,
. stiffeners for the ducts, duct supports, and other inline components such as duct heaters, dampers, etc.
3A.1 Codes and Standards The design of the HVAC ducts and their supports conform to the following codes and standards:
ASME N509-1989, Nuclear Power Plants Air Ventilating Systems and Components I
ASME/ ANSI AG-1 1991, with 1992 and 1993 Agddenda, Code on Nuclear Air and Gas Treatment American Institute of Steel Construction (AISC), Specification for the Design, Fabrication and Erection of Steel Safety Related Structures for Nuclear Facilities, AISC-N690-1984 American Iron and Steel Institute (AISI), Specification for the Design of Cold Formed Steel Structural Members, Parts I and 2,1986 SMACNA, HVAC Duct Constmetion Standards, Metal and Flexible, First Edition 1985.
3A.2 Loads and Load Combinations 3A.2.1 Loads 3 A.2.1.1 Dead Load (D)
Dead load includes the weight of the duct sheet, stiffeners and inline components such as duct I
heaters and dampers. It also includes permariently attached items such as insulation and fireproofing, where applicable, and the weight of the duct supports. Temporary items used i
I during construction or maintenance are removed prior to operation.
Revision: Draft 3 W95tiligh0USe 3A-1 December,1996 Attachr:1ent 5
- 3. Design of Structures, Components, Equipment, and Systems 3 A.2.1.2 Live Load (L)
I Live load consists of a load of 250 pounds to be applied only during construction on an area 1
of 10 square inches on the duct at a critical location to maximize flexural and shear stresses.
'"-'-d "c4edes
!' g av4ty-loads-+wep: We dead ' cad. Live !c=h cear n=!y du-ing tenstmetion/=inten=ce. 'r design, a 250 pcund ' cad m = =a of !0 squ= 'nche is app 4cd a: -'id sp= "f We duct e stiffener e at be :!d pH cf-a p=c! ($at is, b:"/een ad) cent :!ffenes). This load is not combined with seismic loads.
i 3 A.2.1.3 Pressure (P)
The duct metal thickness and stiffener requirements are based on maximum system design pressures. SMACNA or ASME guidelines, as applicable, are used in the design of duct metal thickness and stiffener requirements.
The pressure loads occur during normal plant operation, including plant stan up testing, damper closure and normal airflow. Occasionally, overpressure transient loads such as rapid damper closure may also produce short duration pressure differential.
3 A.2.1.4 Safe Shutdown Earthquake (E,)
Seismic response of the HVAC ductwork and its suppon system are produced due to seismic excitation of the suppons.
3A.2 LS Wind Loads (W)
Ductwork within partially or fully vented buildings are subject to wind effects. Design wind loads are discussed in Section 3.3.
3 A.2.1.6 External Pressure Differential Loads (P )
4 Seismic Category I HVAC ductwork and its supports are designed to withstand dynamic extemal pressure differential loads resulting from postulated accident conditions. Usually HVAC ducts are routed outside the areas of potential pipe break.
3 A.2.1.7 Thermal (To/T )
4 Stresses on the suppons resulting from the ductwork expansion due to temperature changes are avoided by designing the system to take care of the expansion or by utilizing expansion joints. For ducts of gasketed companion angle construction. thermal loads are negligibic. For ducts exposed to higher temperatures during a postulated accident condition. an evaluation is performed on a case by case basis for its effect.
Revision: Draft ow-mea.ao7.oio 97 December,1996 3A 2 W Westiflgh00S8
- 3. Design of Structures, Components, Equipment, and Systems N
3A.2.2 Load Combinations The load combinations for variouiservice levels are as follows:
Service Level Load Combination A
(Normal Operating Condition)
D + L + P + To B
(Severe Condition)
D + W + P + To C
(Extreme Condition)
D + E, + P + To D
(Abnormal Condition)
D + P + P + E, + T 4
3 4
3A.3 Analysis and Design The HVAC duct suppon system is designed to maintain stmetural integrity of the duct.
Function is not required for the seismic Category II ductwork. The stresses are maintained within the allowable limits specified in subsection 3A.3.4.
Stresses in the ductwork are obtained using the normal analysis methods. Section properties and masses are calculated in accordance with SMACNA standard.
The damping values for seismic analysis are as follows:
Welded HVAC Ductwork 4 percent Bolted HVAC Ductwork 7 percent I
The duct design due to pressure loads is based on emphical formulas supponed by tests and I
analyses. The minimum required duct sheet thicknes.: is given by:
I I
t, = 2.5 V (E/f ) (P'/F ) (ac/(a+c))
y y
l I
- Whem, I
i t, = minimum required duct sheet thickness (in) o I
E= modulus of elasticity (psi)
I f, = material yield stress (psi) l P'=
equivalent design pressure for the load combinations in accordance with I
subsection 3A.2.2 (includes the effect of dead load + live load + SSE inertia i
load) (psi) i F.=
allowable membrane + bending stress for duct (psi)
I a=
greater of the duct width or duct height (inches)
I c=
stiffener spacing (inches). This spacing is selected so that a/2 s c 5 2a, and c $
I 96".
I I
The required plastic section modulus, Z, of the frame stiffener is given by:
Revision: Draft T Westingh0USe 3A-3 December,1996
o
- 3. Design of Structures, Components, Equipment, and Systems i
For c2a Z = a ( a'/14) (P/F,)
1 I
a = - a/3 + ( 3+ (a/c)2)in 1
I For c<a.
Z = a c/28 (F/F,) e
- a c/a )2 )
2 1
I a = - c/a + (3+ ( c/a )2 )in i
I The global behavior of the duct is determined from the overall bending of the duct between i
the supports. it is similar to the beam type bending. The dead load is combined with the I
seismic inenial load to determine the maximum bending moment. For detemlining the section I
modulus, the comers of the duct are considered effective. The comer length in each direction I
equals 32 times the thickness of the duct (t) for this purpose.
3A.3.1 Response Due to Seismic Loads The methodology for seismic analysis is provided in subsection 3.7.3 Seismic loads are determined by either using the equivalent static load method of analysis or by performing dynamic analysis.
Stresses are detennined for the seismic excitation in two horizontal and one venical direction.
The stresses in the three directions are combined using the square root of sum of the squares (SRSS) method as described in subsection 3.7.2.6.
3 A.3.2 Deflection Criteria Deflections for panels and stiffeners conform to the limits stated in the Code for " Nuclear Air and Gas Treatment."
3 A.3.3 Relative Movement Clearances are provided for allowing relative movement between equipment. other commodities, and HVAC system.
Revision: Draft os rm7e3cA.mo7.oio 97 December,1996 3A-4
[ W85tiligh0llSe
- 3. Defgn of Structures, Components, Equipment, and Systems l
3A.3.4 Allowable Stresses The basic stress allowables for the HVAC ducts are based on the American Iron and Steel I
institute specification.
l I
Service Level A and B For cross section and segment between I
stiffeners, membrane plus bending is limited to I
0.5 f.
y I
I For duct as a beam, bending stress is limited to I
0.05 f.
y I
i Service Level C and D 1.5 times basic allowable for level A.
The basic stress allowables for duct supports utilizing rolled structural shapes are in accordance with I ANSI /AISC N-690 and the supplemental requirements described in subsection 3.8.4.5.2. The basic stress allowables for supports utilizing light gage cold rolled channel type sections are based on the manufacturer's putished catalog ulues.
He n!!c".2!: c:rc:= fcMhe */2 ic= :.ervice !c:
are = fc"^"
1 Scr;;; Le !
^!!c :b!: Stren i
l Service Level A and B Basic Allowable B
B=ic.^."ew2!e l
Service Level C and D See T2! 3.3.A
' r
^ !SC M ^90 =d ^ !S!;
e.
' (' :"n= b=:e !!cw2!= by n=ufacturer-i 1.6 times basic allowable for tension and 1.4 times basic allowable for I
compression D
See T2!: ? ? A ' '^- ^ !SC " 590 =d ^.!S!;
444hn= b=:c a!!cw2!= by m=uf=:urer i
l 3A.3.5 Connections Connections are designed in accordance with the applicable codes and standards listed in subsection 3A.I. For connections used with light gage cold rolled channel type sections, I
design is based on the manufacturer's published catalog values. Supports are attached to the I
building structure by bolted or welded connections. Fastening of the supports to concrete I
structures meets the supplemental requirements given in subsection 3.8.4.5.1.
i Revision: Draft
[ W85tiflgh0USB 3A-5 December,1996
- 3. Design of Structures, Components, Equipment, and Systems APPENDIX 3F CABLE TRAYS AND CABLE TRAY SUPPORTS This appendix provides the design criteria for seismic Category I cable trays and their supports. Seismic Category 11 cable trays and their supports are also designed utilizing the design criteria of this appendix.
3F.1 Codes and Standards The design of cable trays and their supports conform to the following codes and standards:
American Iron.'nd Steel Institute (AISI), Specification for the Design of Cold Formed Steel Structural Members, Parts 1 and 2.1986 American Institute of Steel Construction (AISC), Specification for the Design, Fabrication and Erection of Steel Safety Related Structures for Nuclear Facilities, AISC-N690-1984 Institute of Electrical and Electronic Engineers (EEE), Standard 344-1987. EEE Recommended Practice for Seismic Qualification of Class IE Equipment for Nuclear Power Generating Stations National Electrical Manufacturers Association (NEMA), Standard Publication No.
VE l-1991, Metallic Cable Tray Systems 3F.2 Loads and Load Combinations 3F.2.1 Loads 3F.2.1.1 Dead Load (D)
I Dead load includes the weight of the cable trays, their supports and the cables inside the trays I
and any permanently attached items.
Temporary items used during construction or I
maintenance are removed prior to operation.
It also includes the weight of Cable tray covers and Other components and fittings 3F.2.1.2 Live Load (L) okarmM30FP.R07 010897 Revision: Draft
! +,tbgh0USe 3F-1 December,1996 l
7
- 3. Design of Structures, Components, Equipment, and Systems Live load consists of a load of 250 pounds to be applied only during construction on the tray at a critical location to maximize flexural and shear stresses. This load is not combined with seismic loads.
3 F.2.1.3 Safe Shutdown Earthquake (E,)
Seismic response of the cable trays and their supports are produced due to seismic excitation of the supports.
3F.2.1.4 Thermal Load These loads are usually not considered and trays are pmvided with expansion joints in accordance with NEMA.
3 F.2.2 Load Combinations The following load combinations are used for designing the cable trays and their suppons:
(a) D+L (b) D+E, 3F.3 Analysis and Design Cable trays and their supports are designed to maintain structural integrity. The stresses are maintained within the allowable limits as specified in subsection 3F.3.3.
Stresses in the cable trays and their supports are obtained using the normal analysis methods.
Section properties and weights of the trays are obtained from manufacturer's data.
3F.3.1 Damping As stated in stubsection 3.7.1.3, the damping ratio used for the AP600 cable tray systems is based on test results presented in Reference 19 (subsection 3.7.6). The cable tray test program conducted by ANCO Engineers Inc. included more than 2000 dynamic tests of representative cable tray system design and construction. The test configurations included items such as various tray types on rigid supports, various tray hanger systems, effects of tray types, effects of strut connections and effects of bracing spacing, unbraced and braced tray systems. Cable ties were also used during the test pmgram. Based on observations during the tests, the high damping values within the cable tray system are provided mainly by the movement, sliding or bouncing of the cables within the tray. The tests show that, for unloaded trays, the damping ratio closely approximates the 7 percent used for bolted structures, and a minimum damping value of 20 percent is maintained with cable ties at spacing greater than or equal to four feet. The tests show that for loaded trays, the damping ratio increases with increased cable loading, reaching a value of 30 percent at cable fill ratio of 50 percent to 100 percent.
Revision: Draft
.3 rr.v7esor.no7-oio 97 December,1996 3F-2 T W85tiligh0ilSO
i
- 3. Design of Structures, Components, Equipment, and Systems The major factors which affect the damping ratio of the cable tray systems are the input acceleration level, cable fill ratio, and the ability of the cables to move within the trays during a safe shutdown earthquake.
The AP600 cable tray system design requires no sprayed-on material for fire protection.
Cable ties are provided at spacing greater than 4 feet, thereby permitting cable movement within the trays. The damping ratio used for the cable tray system is dependent on the level of seismic input and the amount of cable fill within the trays. As shown in Figure 3.7.1-13, the 20 percent constant damping ratio is used for trays loaded to more than 50 percent and subjected to input floor acceleration greater than 0.35g. For cable trays loaded to less than 50 percent and lower than 0.35g input floor accelemtion, linearly interpolated lower damping values are used.
3F.3.2 Seismic Analysis The methodology for seismic analysis is provided in subscction 3.7.3 Seismic loads are determined by either using the equivalent static load method of analysis or by performing dynamic analysis.
Stresses are determined for the seismic excitation in two horizontal and one vertical direction.
The stresses in the three directions are combined using the square root of the sum of the squares (SRSS) method as described in subsection 3.7.2.6.
3 F.3.3 Allowable Stresses The basic stress allowables for the cable trays are based on the American Iron and Steel Institute specification. The basic stress allowables for cable tray supports utilizing light gage cold rolled channel type sections are based on the manufacturer's published catalog values.
The basic stress allowables for cable tray supports utilizing rolled structural shapes are in I
accordance with ANSI /AISC N-690 and the supplemental requirements described in subsection I
3.8.4.5.2.
The allowable stresses for the load combinations are as follows:
D+L Basic Allowable D+E, S^c Table 18.' ' fe: A!SC M 590-ar.d,MS4 444L = bad a!!c'//2!= by m=ufac:u er-1.6 times basic allowable for tension and 1.4 times basic allowable for compression 3F.3.4 Connections Connections an: designed in accordance with the applicable codes and standards listed in subsection 3F.1. For connections used with light gage cold rolled channel type sections, I
design is based on the manufacturer's published catalog values. Supports are attached to the I
building structure by bolted or welded connections. Fastening of the supports to concrete I
stmetures meets the supplemental requirements given in subsection 3.8.4.5.1.
.w.mm.no7.oio 97 Revision: Draft 3 Westinghouse 3F-3 December,1996
or 442.
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l Potentially this could cause column buckling and subsequent collapse.
In buildings ofCategories A, B, and a portion ofC, the K system is permitted 1
l unrestricted by these provisions. For the remainder of Category C as per l
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a TABLE 9.2.2.2 StructuralSystems o Structural System Limitations and Building Height (ft)
Limitauons Py Sensuuc Performance j
Basic Structural System Modancation Deflection Category 7
and Coef!'icient, Amplification l
Seismic Force Resisting System A*
Factor, C/
A&B C
Dd E*
Baartag WallSystem IJght Frame walls with shear panels 6h 4
NL NL 160 100 Reinfoeced concrete shear walls 4h 4
NL NL 160 100 Rainforced masonry shear wn!!s 3h 3
NL NL 160 100 Concentrically-braced bames 4
3h NL Np 160 100 Plain (unreinfotted) masonry sbear walls Ih Ih NL NP NP Plain concrete shear walls Ih Ih NL s
up yp Building Frame System Eccentrically 4 raced frames, moment restsung enaantions at columns away from link 8
4 NL NL 160 100 Eccentrically-twaced names, non-moment resisting eaa-tions at columns away from link 7
4 NL NL 160 100 Light hame wn!!s with shear panels 7
4h NL NL 160 100 ConcentncaDy4 raced homes 5
4h NL NL 160 100 Special wi.!!y braced asme of steel f
5 NL NL 160 100 Asinforced concrete shear walls 54 5
NL NL 160 100 Reinforced masonry shear walls 4h 4
NL Np 160 100 Plain (unreinforced) masonry shear walls Ih Ih NL NP NP Plain concrete shear walls 2
2 NL 8
NP NP Moment Rastering hams System Special moment frames of steel 8
5%
NL NL NL NL Special moment frames of reinforced concrete 8
5%
NL NL NL NL Intermediate moment hames of reinforced concrete 5
4h NL NL NL NL Ordmary moment Dames of steel 4h 4
N NL 160 100 Ordinary moment names orreinforced concrete 3
2h NL NP NP NP DualSystem with a Special Atoment Frume Capable ofResisting at 12 art 25% ofPrescribed Seismic Forces Eocentrically-braced frames, moment resisting j
connections at columns au sy from link 8
4 NL NL NL NL EccentricaDy-braced Dames, non-moment resisting connections at columns awty from link 7
4 NL NL NL NL Concentncally-braced Dames 6
5 NL NL NL NL Special concentrically-braced ihmes of steel I
6h NL NL NL NL Reinforced concrete shear walls 8
6h NL NL NL NL Reinforced masonry shear walls 6%
5h NL NL NL NL Wood ahaanhad shear panels 8
5 NL NL NL NL DualSystem with an latermediate Moment Frams of Rebforced Concrete or an Ordinary Moment Dame of f
Steel Capable ofRasisting atIsast 25% ofPrercrsbed
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Seismie Forces i
Special concentncally braced frames 6
5 NL NL 160 100 Concentncany-braced &ames 5
4h NL NL 160 100 Reinforced concrete shear walls 6
5 NL NL 160 100 Reinforced aiaaaary shear walls 5
4h NL
.NL 160 100 heaWead shear panels 7
4h NL NL 160 100 beversed firndulum Structurus Seismic Force Resisting System Special moment 6ames of structural steel 2%
2%
NL NL NL NL Special moment frames of reinforced concrete 2h 2h NL NL NL NL Orthnary moment &ames of structural steel Ih th NL NL NP NP mRespones modification coefficient, R for use throughout the Srandard. Noar A reducasforces to a samtgen level, not an allowable stress level.
- Deflection amplifkation factor, Ce, for use in Seccons 9 2J.7.1 and 9.2J.7.2.
- NL = Not Limited and NP = Not Permitted For toetric units use 30 m for 100 A and use 50 m for 160 ft.
eSee Section 9.2.2.2.4.1 for a descriptions of bmlding systems limited to buikhngs with a height of 240 A (75 m) or less.
See Sec. 9.2.2.2.4.5 for building systems limited to buildings with a height of 160 A (50 m) or less.
tThe masonry shear walls shan have nommal reinforcement as required by [9.8-1), Section 10.53.2 (ACI 530/ASCE 5).
sPlain concrete shear walls have ->aal reinforsenwns in accordance with Section 10.53.2 of[9.81}.
- See Section A9.6.5.2for limitations on use gfordinary moment concrete Dames in buildings of Seismic Performance Category B on Soil Pro-fue Types E or E 63 s
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