U.S.NUCLEARREGULATORYCOMMISSIONRevisioni*August1977REGULATORYGUIDEOFFICEOFSTANDARDSDEVELOPMENTREGULATORYGUIDE1.90INSERVICEINSPECTIONOFPRESTRESSEDCONCRETECONTAINMENTSTRUCTURESWITHGROUTEDTENDONStA.INTRODUCTIONGeneralDesignCriterion53,ProvisionsforContainmentTestingand.Inspection,ofAppendixA,GeneralDesignCriteriaforNuclearPowerPlants,to10CFRPart50,LicensingofProductionandUtilizationFacilities,requires,inpart,thatthecontainmentbedesignedtopermit(1)appropriateperiodicinspectionofallimportantareasand(2)anappropriatesurveillanceprogram.ThisguidedescribesbasesacceptabletotheNRCstafffordevelopinganappropriatesurveillanceprogramforprestressedconcretecontainmentstructureswithgroutedtendons.TheAdvisoryCommitteeonReactorSafeguardshasbeenconsultedconcerningthisguideandhasconcurredintheregulatorypositionB.DISCUSSIONInserviceinspectionofprestressedconcretecontainmentstructureswithgroutedtendonsisneededtoverifyatspecificintervalsthatthesafetymarginsprovidedinthedesignofcontainmentstructureshavenotbeenreducedasaresultofoperatingandenvironmentalconditions.Groutingoftendonstoprotectthemagainstcorrosionisaproventechnologyinothertypesofstructures.However,thereisasyetnorealexperiencetoadequatelydefinethelong-termcharacteristicsofcontainmentstructureswithgroutedtendons.Themajorconcernincontainmentstructureswithgroutedtendonsisthepossibilitythatwidespreadcorrosionofthe.tendonsteelmayoccurandremainundetected.Themajorfactorsinfluencingtheoccurrenceofcorrosionare(1)thesusceptibilityofthetendonsteeltocorrosion,(2)thedegreeofexposureofthetendonsteeltoa*Thesubstantialnumberofchangesinthisrevisionhasmadeitimpracticaltoindicatethechangeswithlinesinthemargin.tForthepurposeofthisguide,atendonisdefinedasatensionedsteelelementconsistingofwires,strands,orbarsanchoredateachendtoanendanchorageassembly.deleteriousenvironment,(3)theextentoftemperaturevariations,and(4)thequalityofthegroutanditsinstallation.FollowingtherecommendationsofRegulatoryGuide1.107,QualificationsforCementGroutingforPrestressingTendonsinContainmentStructures,couldsignificantlyreducethedangerofwidespreadcorrosion.However,themechanismofcorrosioninallconditionsandsituationsisnotfullyunderstood.Becausemanyparameterscaninfluencethedevelopmentofcorrosionorstresscorrosion,thereisalwaysanareaofuncertaintywithregardtothecorrosionoftendonsteel,anditisnecessarytomonitorthestructureinamannerthatwouldrevealtheexistenceofwidespreadcorrosion.Thisguideoutlinestherecommendationsforinserviceinspectionofcontainmentshavinggroutedtendonsofsizesuptoanultimatestrengthofapproximately1300tons(11,000kN)andconsistingeitherofparallelwiresorofoneorseveralstrands.Thedetailedrecommendationsoftheguidearenotdirectlyapplicabletogroutedtendoncontainmentshavingbartendons.However,theinserviceinspectionprogramforgroutedtendoncontainmentswithbartendonsmaybedevelopedusingtheprinciplesinthisguideandwillbereviewedbytheNRCstaffonacase-by-casebasis.Thisguidedoesnotaddresstheinserviceinspectionofprestressingfoundationanchors.Iftheyareused,theinserviceinspectionprogramwillbereviewedbytheNRCstaffonacase-by-casebasis.Inserviceinspectionofthecontainmentlinerandpenetrationsisalsonotaddressedinthisguide.Thesimplestmeansofmonitoringtheseprestressedconcretestructureswouldbetoascertaintheamountofprestressatcertainstrategicallylocatedsectionsinthestructure.However,itisgenerallyfeltthatavailableinstrumentationforconcrete,i.e.,straingages,stressmeters,andstrainmeters,isnotreliableenoughtoprovidesuchinformation.WhenUSNRCREGULATORYGUIDESCommentsshouldbesenttotheSecretaryoftheCommission,US.NuclearRegulatoryCommission,Washington,D.C.20555,Attention:DocketingandServiceRegulatoryGuidesareissuedtodescribeandmakeavailabletothepublicmethodsBranch.acceptabletotheNRCstaffofimplementingspecificpartsoftheCommission'sregulations,todelineatetechniquesusedbythestaffinevaluatingspecificproblemsTheguidesareissuedinthefollowingtenbroaddivisions:orpostulatedaccidents,ortoprovideguidancetoapplicants.RegulatoryGuidesarenotsubstitutesforregulations,andcompliancewiththemisnotrequired.t.PowerReactors6.ProductsMethodsandsolutionsdifferentfromthosesetoutintheguideswillbeaccept2.ResearchandTestReactors7.Transportationiftheyprovideabasisforthefidingsrequisitetotheissuanceorcontinuance3.FuelsandMaterialsFacilities8.OccupationalHealthableovidensbathefindin.4.EnvironmentalandSiting9.AntitrustReview5.MaterialsandPlantProtection10.GeneralCommentsandsuggestionsforimprovementsintheseguidesareencouragedatallRequestforsinglecopiesofissuedguideswhichmaybyreproduced;orforplacetimes,andguideswillberevised,asappropriate,toaccommodatecommentsandmestonsanautomaticdistributionlistforsinglecopiesoffutureguidesiiispecifictoreflectnewinformationorexperience.ThisguidewasrevisedasaresultofdivisionsshouldbemadeinwritingtotheUS.NuclearRegulatoryCommission,substantivecommentsreceivedfromthepublicandadditionalstaffreview.Washington,D.C.20555,AttentionDirector,DivisionofDocumentControl.instrumentationthateithercanberecalibratedorreplacedincaseofamalfunctionorisproventobesufficientlyreli