1、ANSI/ANS-2.26-2004categorization of nuclear facility structures,systems, and components for seismic designANSI/ANS-2.26-2004ANSI/ANS-2.26-2004American National StandardCategorization of Nuclear FacilityStructures, Systems, and Componentsfor Seismic DesignSecretariatAmerican Nuclear SocietyPrepared b
2、y theAmerican Nuclear SocietyStandards CommitteeWorking Group ANS-2.26Published by theAmerican Nuclear Society555 North Kensington AvenueLa Grange Park, Illinois 60526 USAApproved December 2, 2004by theAmerican National Standards Institute, Inc.AmericanNationalStandardDesignation of this document as
3、 an American National Standard attests thatthe principles of openness and due process have been followed in the approvalprocedure and that a consensus of those directly and materially affected bythe standard has been achieved.This standard was developed under procedures of the Standards Committee of
4、the American Nuclear Society; these procedures are accredited by the Amer-ican National Standards Institute, Inc., as meeting the criteria for AmericanNational Standards. The consensus committee that approved the standardwas balanced to ensure that competent, concerned, and varied interests havehad
5、an opportunity to participate.An American National Standard is intended to aid industry, consumers, gov-ernmental agencies, and general interest groups. Its use is entirely voluntary.The existence of an American National Standard, in and of itself, does notpreclude anyone from manufacturing, marketi
6、ng, purchasing, or using prod-ucts, processes, or procedures not conforming to the standard.By publication of this standard, the American Nuclear Society does not insureanyone utilizing the standard against liability allegedly arising from or afterits use. The content of this standard reflects accep
7、table practice at the time ofits approval and publication. Changes, if any, occurring through developmentsin the state of the art, may be considered at the time that the standard issubjected to periodic review. It may be reaffirmed, revised, or withdrawn atany time in accordance with established pro
8、cedures. Users of this standardare cautioned to determine the validity of copies in their possession and toestablish that they are of the latest issue.The American Nuclear Society accepts no responsibility for interpretations ofthis standard made by any individual or by any ad hoc group of individua
9、ls.Requests for interpretation should be sent to the Standards Department atSociety Headquarters. Action will be taken to provide appropriate response inaccordance with established procedures that ensure consensus on theinterpretation.Comments on this standard are encouraged and should be sent to So
10、cietyHeadquarters.Published byAmerican Nuclear Society555 North Kensington AvenueLa Grange Park, Illinois 60526 USACopyright 2004 by American Nuclear Society. All rights reserved.Any part of this standard may be quoted. Credit lines should read “Extracted fromAmerican National Standard ANSI0ANS-2.26
11、-2004 with permission of the publisher,the American Nuclear Society.” Reproduction prohibited under copyright conventionunless written permission is granted by the American Nuclear Society.Printed in the United States of AmericaForeword(This foreword is not part of American National Standard Categor
12、ization of NuclearFacility Structures, Systems, and Components for Seismic Design, ANSI0ANS-2.26-2004.)This standard has been developed based on methods used by the U.S. Depart-ment of Energy (DOE) for performance categorizing and designing structures,systems, and components (SSCs) in nuclear facili
13、ties to withstand the effects ofnatural phenomena (DOE-STD-1021-93, “Natural Phenomena Hazards Perfor-mance Categorization Guidelines for Structures, Systems, and Components,”July 1993, Reaffirmed 2002; DOE-STD-1020-2002, “Natural Phenomena Haz-ards Design and Evaluation Criteria for Department of E
14、nergy Facilities,” Jan-uary 2002; DOE-STD-1022-94, “Natural Phenomena Hazards Site CharacterizationCriteria,” March 1994, Reaffirmed 2002; DOE-STD-1023-95, “Natural Phenom-ena Hazards Assessment Criteria,” March 1995, Reaffirmed 2002).This standard provides criteria and guidance for selecting a seis
15、mic designcategory (SDC) and Limit State for the SSCs with a safety function in a nuclearfacility, other than commercial power reactors, whose seismic design require-ments are established by other standards and regulations. The SDC and LimitState are to be used in conjunction with standards ANS-2.27
16、, “Criteria forInvestigations of Nuclear Materials Facilities Sites for Seismic Hazard Assess-ments”; ANS-2.29, “Probabilistic Seismic Hazard Analysis”; and ANSI0ASCE0SEI 43-05, “Seismic Design Criteria for Structures, Systems and Components inNuclear Facilities.” These standards together establish
17、the design response spec-tra and the design and construction practices to be applied to the SSCs in thefacility, dependent on which SDC and Limit State are assigned to the SSC. Theobjective is to achieve a risk-informed design that protects the public, the envi-ronment, and workers from potential co
18、nsequences of earthquakes. Applicationof this group of standards will produce (a) the design response spectra, (b) theSSC Limit State necessary to achieve adequate safety performance during andfollowing earthquakes, and (c) SSC designs that achieve the desired Limit State.Referenced standards and th
19、eir procedural relationship to this standard arediscussed in Appendix A of this standard.Working Group ANS-2.26 of the Standards Committee of the American NuclearSociety had the following membership at the time of approval of this standardand indeed was stable throughout the development of the stand
20、ard:N. W. Brown (Chairman), Lawrence Livermore National LaboratoryS. Additon, Rocky Flats Environmental Technology SiteH. Chander, U.S. Department of EnergyD. Guzy, U.S. Department of EnergyA. Hadjian, Defense Nuclear Facilities Safety BoardQ. Hossain, Lawrence Livermore National LaboratoryC. Morrel
21、l, Shaw Group, Inc.A. Persinko, U.S. Nuclear Regulatory CommissionH. C. Shaffer, ConsultantJ. D. Stevenson, ConsultantC. M. Vaughan, Global Nuclear FuelThis standard was prepared under the guidance of Subcommittee 21, DesignCriteria0Operations, of the American Nuclear Society. At the time of the bal
22、lot,Subcommittee 21 was composed of the following members:R. M. Ruby (Chairman), Constellation EnergyC. H. Moseley (Vice Chairman), BWXT Y-12T. Dennis (Secretary), IndividualN. Brown, Lawrence Livermore National LaboratoryC. Eldridge, Pacific Gas (b) the magnitude of any hazard involved;(c) the life
23、 cycle stage of the facility; (d) theprogrammatic mission of a facility; (e) the par-ticular characteristics of the facility; (f) therelative importance of the radiological and non-radiological hazards; and (g) any other rele-vant factor.Limit State: The limiting acceptable deforma-tion, displacemen
24、t, or stress that an SSC mayexperience during or following an earthquakeand still perform its safety function. Four LimitStates are identified and used by this standardand ANSI0ASCE0SEI 43-05 1.2)seismic design category (SDC): One of fivecategories used in this standard and the accom-panying three s
25、tandards identified in AppendixA that are used to establish seismic hazards eval-uations and SSC seismic design requirements.target performance goal: Target annual fre-quency of an SSC exceeding its specified LimitState. Target performance goals of 1 3 10240year, 4 3 10250year, and 1 3 10250year are
26、 usedin ANSI0ASCE0SEI 43-05. The importance oftarget performance goals in this standard isdiscussed in Appendix A.total effective dose equivalent: The sum ofthe deep-dose equivalent (for external expo-sure) and the committed effective dose equiva-lent (for the internal exposure).unmitigated conseque
27、nces: The product of aspecific type of consequence analysis used forthe selection of the SDC for an SSC. Unmiti-gated consequence analysis is described in 6.2.3 ApplicabilityThis standard is applicable to the design ofSSCs of nuclear facilities. For the purpose ofthis standard, a nuclear facility is
28、 a facilitythat stores, processes, tests, or fabricates ra-dioactive materials in such form and quantitythat a nuclear risk to the workers, to the off-site public, or to the environment may exist.These include but are not limited to nuclearfuel manufacturing facilities; nuclear materialwaste-process
29、ing, storage, fabrication, and re-processing facilities; uranium enrichment facil-1)The SDCs used in this standard are not the same as the SDCs referred to in the International BuildingCode (IBC).2)Numbers in brackets refer to corresponding numbers in Section 7, “References.”1ities; tritium producti
30、on and handling facilities;radioactive materials laboratories; and nuclearreactors other than commercial power reactors.(Commercial power reactors are excluded be-cause their seismic design requirements arespecified by other American Nuclear Societystandards.)The SSC seismic design categories that t
31、hisstandard establishes shall be used by the facil-ity owner and the facility designer, in conjunc-tion with ANS-2.27, “Criteria for Investigationsof Nuclear Materials Facilities Sites for Seis-mic Hazard Assessments” 2; ANS-2.29 “Prob-abilistic Seismic Hazard Analysis” 3; andAmerican Society of Civ
32、il Engineers (ASCE)standard ANSI0ASCE0SEI 43-05, “Seismic De-sign Criteria for Structures, Systems and Com-ponents in Nuclear Facilities” 1.4 Determination of SSC SeismicDesign Categories4.1 IntroductionSSCs that have been determined to have a safetyfunction shall be assigned one of five SDCs. AnSSC
33、 shall be considered to perform a safetyfunction if its failure, by itself or in combina-tion with other SSCs, could result in any of theconsequence levels identified in Table 1 beingexceeded. In addition, an SSC, the failure ofwhich may adversely affect an operator actionthat is required for restor
34、ing another SSC safetyfunction or for preventing or mitigating theconsequences of a design-basis earthquake(DBE) during and following the event, shall beconsidered to have a safety function. The iden-tification of SSCs with safety functions is theproduct of the safety analyses required to sup-port a
35、pplication of this standard. Section 6 out-lines the scope of the safety analysis required.The scope and comprehensiveness of the safetyanalysis will vary with the complexity of thefacility, its operations, and the contained hazard.The assignment of an SDC to an SSC deter-mined to have a safety func
36、tion is based onthe objective of achieving acceptable risk tothe public, the environment, and workers re-sulting from the consequences of failure of theSSC (see Appendix A for additional discussion).Each SDC has a defined consequence severitylevel that shall not be exceeded. Proper assign-ment of SD
37、Cs to the SSCs and constructing3)the SSCs in accordance with the InternationalBuilding Code (IBC) or Standard ANSI0ASCE0SEI 43-05 as required will provide an accept-ably low risk to the public, the environment,and workers from seismic-induced SSC failures.4.2 Categorization Process4.2.1One of the SD
38、Cs listed in Table 1 shall beassigned to the SSCs based on the unmitigatedconsequences that may result from the failureof the SSC by itself or in combination withother SSCs. If the SSC failure consequencesare equal to or less than the guidance listed inTable 1 for a given SDC, the SSC shall beplaced
39、 in that SDC. The consequences shall beequal to or less for all three types of conse-quences listed in Table 1 (i.e., consequences tothe public, the environment, and workers), andthe SSC shall be placed in the highest SDCdetermined under the consequence type. Sec-tion 6.2 provides guidance on perfor
40、ming un-mitigated consequence evaluations.4.2.2SDC-1 and SDC-2 in conjunction with the IBCand SDC-3, SDC-4, and SDC-5 in conjunctionwith ANS-2.27, ANS-2.29, and ANSI0ASCE0SEI 43-05 establish the design response spec-tra (DRS) and SSC design and analysisrequirements. For SDC-3, SDC-4, and SDC-5,the D
41、RS are specified as the product of theuniform hazard response spectra obtained usingANS-2.27 and ANS-2.29, and a design factorspecified in ANSI0ASCE0SEI 43-05. The DRSfor SDC-1 and SDC-2 are specified in the IBC.4.2.3Based on the information or data obtained fromthe safety analyses outlined in Secti
42、on 6 andthe guidance provided here, SSCs assignedSDC-3, SDC-4, or SDC-5 shall also be assignedone of four Limit States that are identified in3)“Constructing” includes design, fabrication, erection, excavation, material selection, material qualificationinspection, testing, administrative control, doc
43、umentation, and quality assurance.American National Standard ANSI0ANS-2.26-20042Table 1 SDCs based on the unmitigated consequences of SSC failureUnmitigated Consequence of SSC FailureCategory Worker Public EnvironmentSDC-1a)No radiological0toxicological releaseconsequences but fail-ure of SSCs may p
44、lacefacility workers at riskof physical injury.No radiological0toxicological releaseconsequences.No radiological0toxicological releaseconsequences.SDC-2a)Radiological0toxicological exposuresto workers will have nopermanent health ef-fects, may place morefacility workers at riskof physical injury, or
45、may place emergencyfacility operations atrisk.Radiological0toxicological exposuresof public areas aresmall enough to re-quire no public warn-ings concerning healtheffects.No radiological orchemical environmentalconsequences.SDC-3 Radiological0toxicological exposuresthat may place facilityworkers lon
46、g-termhealth in question.Radiological0toxicological exposuresof public areas wouldnot be expected to causehealth consequencesbut may require emer-gency plans to assurepublic protection.No long-term environ-mental consequencesare expected, but envi-ronmental monitoringmay be required for aperiod of t
47、ime.SDC-4 Radiological0toxicological exposuresthat may cause long-term health problemsand possible loss of lifefor a worker in proxim-ity of the source ofhazardous material, orplace workers innearby on-site facilitiesat risk.Radiological0toxicological exposuresthat may cause long-term health problem
48、sto an individual at theexclusion area bound-ary for 2 hours.Environmental moni-toring required andpotential temporaryexclusion from selectedareas for contamina-tion removal.SDC-5 Radiological0toxicological exposuresthat may cause loss oflife of workers in thefacility.Radiological0toxicological expo
49、suresthat may possiblycause loss of life to anindividual at the exclu-sion area boundary foran exposure of 2 hours.Environmental moni-toring required andpotentially permanentexclusion from selectedareas of contamination.a)“No radiological0toxicological releases” or “no radiological0toxicological consequences” means thatmaterial releases that cause health or environment concerns are not expected to occur from failures ofSSCs assigned to this category.American National Standard ANSI0ANS-2.26-20043Section 5. Appendix B provides examples ofhow this determination may be made. The setof
