Transcript
T h e S h o c k e y P r e c a s t G r o u p
PARKING STRUCTURE
DESIGN GUIDE2008/2009 Edition
Parking Structure Design Guide2008/2009 Edition
Introduction
48’ Bay System
Parking Structure Aesthetics
The AltusGroup
Shockey Parking Structure Specifications
Glossary
• WhyPrecast?• WhyShockey?
• OptimalLayout• Openness• RampWalls• DrySystem
• Colors,Features,Textures• CaseStudies • CalvertSt.ParkingStructure • WashingtonNationalsBallpark ParkingStructure • GaylordNationalHarborResort &ConventionCenter
• C-GRID®ReinforcedDoubleTeesfor ParkingStructures
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T h e S h o c k e y P r e c a s t G r o u p
219 Stine Lane
Winchester, VA 22603
540.667.7700
www.shockeyprecast.com
NOTE: Thedetailsshowninthisdesignguideareintendedtobehelpfulinthepreparationofcompleteproject plans. These details are not to be used asworkingdrawings.Workingdrawingsanddetailsmustbepreparedandapprovedbyqualifiedprofessionalscertifiedinthejurisdictioninwhichtheprojectistobebuilt. Shockey acceptsno responsibility for anyerrorsoroversightsintheuseofthismaterialorinthepreparationofplans.Thispublicationisintendedforusebyprofessionalpersonnelcompetenttoevaluatethe significance and limitations of its contents andable to accept responsibility for the application ofthe material contained herein. Special conditionsandspecific local requirementsonyourprojectwillrequirespecificevaluationandpracticalengineeringjudgmentbytheproject’sEngineerofRecord.
©TheShockeyPrecastGroup2008.AllRightsReserved.
FairfaxCountyJudicialCenterParkingStructure,Richmond,VA
INTRODUCTIONAsthecostofrealestatecontinuestorise,ownersanddevelopersareingreaterneedofparkingsolutionsthatprovidesmartandcost-effectiveanswerstoavarietyofcommercial,residential,municipal,andinstitutionalparkingneeds.Inadditiontothepracticalissuesrelatingtoparkingavailabilityandcost,theseownersandgoverningbodiesareplacinganincreasedemphasisonaesthetics.Today’sparkingstructuremustbeconvenientlylocated,low-cost,andcomplementthesurroundinglandscape.
Inthischapterwewillexplorethenumerousbenefitsprecastconcreteoffersforowners,designersandgeneralcontractors,including:• Speed-to-market• Durability• Sustainability• 50-YearLifeExpectancy• IntegratedProjectDelivery• IncreasedValuefortheOwner• OpennessandSecurity
Why Precast?Whyaremoreownersanddesignersselectingprecastconcreteasthematerialofchoicefortheirparkingstructureprojects?Theanswerissimple.Precastconcreteisahighlydurable,economicalandversatilebuildingmaterialthatoffersincomparablevalueandflexibility.Itsshorterectiontimeandabilitytoreducetheoverallconstructionscheduleappealtoownersandgeneralcontractors.Fordesigners,precastopensthedoortoaworldofliterallylimitlesspossibilitiesforproviding“signature”solutionstotheirindividualparkingneeds.
Speed-to-MarketThedecisiontodesignwithprecastconcretecarrieswithitamyriadofadvantagesovercast-in-place(CIP)concreteorothertraditionalconstructionmaterials.OneoftheforemostbenefitsofusingprecastratherthanCIPconcreteisthattheprecastmanufacturingprocessisunaffectedbytemperatureoradverseweatherconditions.Precastconcretecomponentsarefabricatedinacontrolledplantenvironment,whichmeansthatvaluableprojecttimeisnotlostwaitingforacceptableweatherconditions.
Typicalprecastparkingstructurecomponentssuchasdoubletees,columnsandinvertedteebeamscaneasilybeerectedatanaveragerateof12piecespercraneperday,andcanbeerectedinweatherconditionsthatwouldbeproblematicforthefullerectionofsteelcomponentsorCIPconcrete.Precastconcrete’sfastererectionmeansfollow-ontradescanbeginworkmorequicklyandtranslatestoanoverallconstructionschedulethatmaybeseveralmonthsshorterthanthatofaprojectusingCIPconcrete.
Forgeneralcontractors,thisschedulereductionresultsinaneconomicadvantageduetosignificantlyreducedoverhead(generalconditions)andincreasedavailabilityofthefirm’screwsforotherprojects.
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DurabilityOneofprecastconcrete’sforemostadvantagesisitsdurability.Plant-castprecastproductsaretypicallymoredurablethanfield-placedconcreteinpartbecauseofthecontrolledenvironmentinwhichtheyaremanufactured.Thelowwater-cementratiousedinprecastconcretecreatesadenserproductthatdoesnotallowpenetrationofchloridesandotherharmfulelementsaseasilyasfield-placedconcrete.ThePrecastPrestressedConcreteInstitute(PCI)PCIHandbook6thEditionreportsthatstudieshaveshown“acceleratedcuringmakesprecastconcretemoreresistanttochloridesthanfield-curedconcrete.”
TheShockeyPrecastGroupcanuseflyash,silicafume,slagcementandothercementitiousmixturestohelpreducethewater/cementratiooftheconcretemix,increasedensity,reducealkalisilicareactivity,andincreasethelong-termstrengthanddurabilityofourprecastconcretecomponents.Theuseofcorrosioninhibitorsandgalvanizedorepoxy-coatedreinforcingintheprecastconcretecanfurtherincreasedurability.Topreventcorrosionofconnectionsandtomaximizethelifespanofaparkingdeck,TheShockeyPrecastGroupusesstainlesssteelflange-to-flangeconnectionsinthedrivingsurfacewherethemajorityofnormalwear-and-tearwilloccur.
SustainabilitySilicafume,flyash,andslagcementareallconsidered“green”productsandtheiruseaspartoftheoverallconcretemixcanaddLEEDpointstoaproject.
50-Year Life ExpectancyInaccordancewiththeLife-365ServiceLifePredictionModel™,usingslagwithacorrosioninhibitorinournormalconcretemixtures,itcanbeshownthatwitha1.9”covertosteelinourhorizontalprecastcomponents,TheShockeyPrecastGroupisabletoprovideparkingstructuresthatmeeta50-yearlifeexpectancy.
Intheeventaprimaryflangereinforcementisusedthatcannotcorrode(suchastheC-GRID®carbonfiberreinforcingsystem),durabilityofthedoubleteeswillbesignificantlygreaterthanthatofdoubleteesreinforcedwithweldedwirefabric.
Pleasenotethatachievinga50-yearlifeexpectancyiscontingentuponpropermaintenanceasoutlinedinPCI’sMaintenanceGuide,includingimmediaterepairofcracksandtimelyreplacementofjointsealantstomaintainprotectionofconnections.
Integrated Project DeliveryStructuralprecastcomponentscanbeerectedinarelativelyshortperiodoftimebecausetheyinterlocktosupportoneanother.Simplerinstallationrequiresfewercrewmembers,whichtranslatestolesstraffic,congestionandwasteonthejobsite.Forthegeneralcontractor,acleanerandsaferjobsitemeanslessriskandmoreassuranceofasmoothandsuccessfulprojectflow.AndbecauseTheShockeyPrecastGroupmanufacturesanderectsitsprecastcomponents,thegeneralcontractorcanrelyonasolesubcontractorforprojectcompletion.
Increased Value to OwnerFortheowner,the“speedtomarket”ofprecastmeansfasterdeliveryofthefinishedparkingstructure,whichcanresultinsignificantcostsavingsandtranslatetoafasterreturnoninvestment.Thedurabilityandlongevityofaprecastparkingstructurealsoequalsabetterlong-terminvestmentfortheowner.Aspreviouslystated,theinherentquality,strengthanddensityofprecastconcreteproducedbyTheShockeyPrecastGroup,combinedwith
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aregularmaintenanceprogram,canresultinaparkingstructurewithatypicallifecycleof40-50years–fargreaterthanthetypicallifecycleofaCIPparkingstructure.Fortheowner,thisrepresentsasignificantreturnontheinitialinvestment.
Openness and SecurityAnyonewhohaseverparkedinadimly-lit,closed-inparkinggarageunderstandsperfectlytheaestheticandsecurity-relatedadvantagesofaprecastparkingstructure.Theuseoflong-spanprecastdoubleteesandarchitecturalload-bearingspandrelsorload-bearingwallsallowdesignerstocreateparkingstructureswithwidebaysthatgivepatronsanincreasedsenseofvisibilityandsecurity.Theendresult?Morepatronsarelikelytousetheprecastparkingstructurethanadimly-lit,closed-inCIPparkingstructure.
Why Shockey?
The Shockey PedigreeWhychooseTheShockeyPrecastGroup?TheShockeypedigreeissynonymouswithquality,integrity,anddoingajobrightthefirsttime.Ourhistorystretchesbackmorethan100years,encompassinggeneralcontracting,designbuildandprecastconcreteservices.
In1896,HowardShockeystartedawagon-repairbusinessinWinchester,Virginia.ThebusinessgrewtoincludegeneralcontractingandHoward’sreputationforqualityconstructionanddo-it-right-the-first-timeattitudequicklyputhiscompanyindemandforcustomhomebuilding.Today,manyofthehomeshebuiltattheturnofthecenturyarestillstanding;monumentstohislegacyofhardwork,integrity,anddedication.Howardpassedthatlegacytohissons,andinthe1930s,JimShockeyjoinedhisfatherinthebusiness.HewaslaterfollowedbyhisbrotherRalph.In1947,thecompanybecameknownasHowardShockeyandSons.
In1955,ShockeyopenedasmallmanufacturingfacilityforprestressedconcreteasadivisionofCrider&Shockey,itsformerready-mixconcretecompany.Oneyearlater,ShockeyBrothers,Inc.becamethethirdShockeyoperatingcompany.In1999,thecompanychangeditsnametoTheShockeyPrecastGroup.Today,TheShockeyPrecastGrouphascompletedmorethan3,000precastprojectsthroughouttheMid-Atlanticregion,includingtheserecentnoteworthyparkingstructures:• CalvertSt.ParkingStructure,Annapolis,MD•D.C.NationalsBallparkParkingStructures,Washington,D.C.•GaylordNationalHarborResort&ConventionCenterParkingStructure, OxenHill,MD• JohnPaulJonesArenaParkingStructure,Charlottesville,VA•CarilionHealthcareRiversideParkingStructure,Roanoke,VA• ShadyGroveMetroStationParkingStructure,ShadyGrove,MD• FairfaxJudicialCenterParkingStructure,Fairfax,VA
TheShockeyPrecastGroupisachartermemberofthePrecast/PrestressedConcreteInstitute,aswellasbeingaPCI-CertifiedPlantandPCICertifiedErector.ShockeyPrecastmanagementhasheldleadershippositionsinMAPA,the
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Shockey Bros, Inc. casting yard, circa 1960s.
Shockey Bros., Inc. – prestressing double tees, circa 1960s.
PCIchairmanship,variousPCItechnicalcommittees,andonthePCIIndustryAdvisoryGrouptotheNationalBuildingInformationModelingStandardInitiative.TheShockeyPrecastGroupisalsoamemberoftheAltusGroup–acollaborationofprecastersdedicatedtoadvancingtheuseofC-GRID®carbonfiberreinforcing.
Sole SourceTheShockeyPrecastGroupprovidestheOwner,DesignerandGeneralContractorwithasinglepointofcontactforthefullrangeofprecastactivitiesfrominitialcoordinationanddesignthroughturnoverofthebuildingtotheowner.With50+yearsintheproductionanderectionofprecastconcrete,TheShockeyPrecastGroup’sexperienceintheparkingstructurearenaisunmatchedintheregion--makingustrulyThe Partner of Choice.
TheShockeyteamassiststheOwnerorGeneralContractorthroughtheentiredesignandconstructionprocessstartingwithearlybudgetinginformation.Westrivetobepartoftheearlydesignprocess,providingexperience-basedbudgetsinsupportofspecificprojectplanstoassisttheOwnerorGeneralContractorinlong-termfinancialforecastingofprojects.Asplanningcontinuesanddetailsofthestructurebecomemoredefined,weassistindefiningthecostofaprecaststructurebyofferingacomprehensiveproposalfortheproject.
TheprojectproposalincludesadetailedengineeringandproductionschedulethatenablestheOwnerorGeneralContractortomeetprojecterectionneeds.TheShockeyPrecastGrouptypicallyassiststheOwnerandGeneralContractorbyprovidingqualitycoordinationeffortstotheteamthroughoutthedesigndevelopmentprocess.
Shockey’steamincludesfield-experiencedcoordinatorswhospecializeinonsitemanagementofpre-erectionactivitiestofacilitateasmoothtransitiontotheerectionphaseoftheproject.Ourtransportationcoordinatorsensurethesitelogisticsdetailsareplannedwellinadvancetoallowforuninterruptederectionoftheprecast.Aftererectioniscompletedorhasadvancedtoasafedegree,ourFieldCoordinatorsprovideearlyaccessto
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The Shockey Precast Group Winchester Plant
thestructureforfollow-ontrades.Thistimelyonsitecoordinationminimizesdisruptionsoffieldactivitiesandreducestheoverallprojectconstructionschedule.
Duringerectionofthebuilding,TheShockeyPrecastGroup’sfieldfinisherscompletetheonsitework--enablingtheprecastportionofthestructuretobecompletedwithinamonthoferectioncompletion.Thisquickresponseallowspunch-listreviewofthestructuretoproceedwithoutdelay.Finally,uponcompletionoftheprecastwork,weprovideanindustry-leadingmanualforcareandmaintenanceofparkingfacilities,alongwithawarrantyofourwork.Ownerswhofollowthecyclicmaintenanceactivitiesoutlinedinthismanualandwhohavetrainedpersonnelresponsibleforthecareoftheirparkingstructurewillensurethestructuremeetsorexceedstheservicelifeobjectives.TheShockeyPrecastGroup’sfieldrepresentativesalsoprovideexperience-basedassistancetotheownersonanas-neededbasisduringparkingstructureoperations.
Fromdesigndevelopmentthroughon-lineoperations,TheShockeyPrecastGroupprovidesone-stopserviceforalltheactivitiesnecessarytobringanewparkingstructuretoreality.
Design Assist ProgramIn1996,legislationwaspassedthatenabledthefederalgovernmenttoenterintodesign-buildcontracts.Sincethattime,therehasbeenadramaticriseinthenumberoffederally-fundeddesign-buildprojects.Asaresult,theneedforspecialtysubcontractorstosupportthissignificantincreasehasneverbeengreater.
TheShockeyPrecastGrouptypicallyseekstobecomeinvolvedinthedevelopmentofprojectsthatarelessthan15%designed.EarlyinvolvementinthedesignprocessenablesTheShockeyPrecastGrouptohelpourcustomersmakesound,informedchoicesthatbestservethefinancialandaestheticneedsoftheowner.
Design Assistance ServicesTheShockeyPrecastGroupprovidesthefollowingdesignassistanceservicestoourcustomers:1. Prepareandupdatebudgetestimates.2. Participateinconstructabilityreviews.3. Supportvalueengineeringoptions.4. AttendmeetingswiththeA/EDesignTeamasrequired.5. ProvideassistancetotheA/EDesignTeamintheformofconstructiondetails,loading concepts,productsamples,anddrawingsfromsimilarproducts.
6. Participateinregularphone,written,andemailcommunicationswiththeA/EDesign
Teamduringthedevelopmentofthedesignthrough100%ConstructionDocuments.
7. UseBIMProcesstoprovide3Dprojectmodels.
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FrequencyTheShockeyPrecastGroupprovidesdesignassistprogramserviceswiththefollowingfrequency:1. AtCoreandShell100%DesignDevelopmentDocuments.2. At10%,50%,and100%ConstructionDocuments.
Building Information Modeling (BIM)“ABuildingInformationModel(BIM)isadigitalrepresentationofphysicalandfunctionalcharacteristicsofafacility.Assuchitservesasasharedknowledgeresourceforinformationaboutafacilityformingareliablebasisfordecisionsduringitslife-cyclefrominceptiononward.
AbasicpremiseofBIMiscollaborationbydifferentstakeholdersatdifferentphasesofthelifecycleofafacilitytoinsert,extract,updateormodifyinformationintheBIMtosupportandreflecttherolesofthatstakeholder.TheBIMisashareddigitalrepresentationfoundedonopenstandardsforinteroperability.”—NationalInstituteofBuildingSciences
TheShockeyPrecastGroup’sEngineeringdepartmenthasplayedanintegralroleinthedevelopmentofBIMfortheprecastindustrythroughitspartnershipwithTEKLAStructures.ThiscommitmenttoremainingattheforefrontofBIMtechnologyhasmadeTheShockeyPrecastGroupinstrumentalintheadvancementanduseofBIMthroughouttheprecastindustry.Forourcustomers,TheShockeyPrecastGroup’sextensiveknowledgeanduseofBIMtechnologymeanswecanmaximizetheeffectivenessofthisvaluableintegrationtooltoensuresmoothprojectflowandopenteamcommunication.
Safety: First at All LevelsTheShockeyPrecastGroupiscommittedtoprovidingasafeandhealthfulworkenvironmentforallouremployeesandotherswhomaywork,visit,orenterourfacilitiesorjobsites.Itisourpolicytoconductbusinessinamannerthatoffersmaximumprotectiontoeachandeveryemployeeandanypersonthatmaybeaffectedbyouroperationsandbusiness.Wewillmakeeveryefforttoprovideaworkingenvironmentthatisfreefromanyrecognizedorpotentialhazard.ThecommitmentisbestdescribedbytheShockeymaxim–Safety: First at all levels.
Thegroundworkforasafeandsuccessfulprojectisestablishedlongbeforethefirstpieceofprecastisdeliveredtothesite.TheShockeyPrecastGroupisproudofitsthoroughpre-constructionplanningandsafeexecutionofallworkactivities.Shockeymanagersandfieldoperationsexpertsmentallybuildtheproject,anticipatingasmanyissuesaspossiblethatcouldadverselyaffecttheprogressoftheworkonsite.Thoroughon-sitereviewofaccessrequirementsforthecraneandtruckstransportingtheprecastarediscussedlongbeforethefirstlayeroftopsoilisdisturbed.
Duringtheprojectproposalstage,theFieldOperationsManager,withassistancefromTheShockeyPrecastGroup’sEstimatingDepartment,usesavailablecontractdocumentstodeterminethesafestandmosteconomicalmethodforerectingtheprecast.TheFieldOperationsManagerdeterminesrequiredaccessforthecraneandestablishesthesizeofthecrane,lengthsofboom,andboomconfigurationrequiredtosafelyerecttheprecastwellwithinthecrane-specifiedcapacities.Anaccesssketchshowingtherequiredcranepathisprovidedwitheachproposal.Additionally,thecranegeometry(length,width)andthemaximumcranebearingpressureareprovidedsotheownercandeterminecostsfor
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providingstabilizedcraneaccessandastablebasecoursetosupportthetrucksprovidingprecastdeliverytothesite.
ErectionoftheprecastisperformedbyerectorsQualifiedunderPCI’sErectorCertificationProgram.PCI-QualifiedErectorsmustundergoarigorousauditoftheirerectionoperationsatleasteverysixmonths.Anydeficienciesfoundduringtheauditsareimmediatelycorrected.Follow-upauditsensurecontinuedcompliancewiththissafety-orientedCertificationProgram.
Duringthedesigndevelopmentstageofallawardedprojects,theprecastdesignengineerusestheerectionplantodetermineifadditionalerectionbracingisrequired.Theprecastdesignengineerevaluatesthestabilityofthepartiallyerectedstructuretoensureitcanwithstandthemostsevereweatherconditionsatanypointduringerection.Ifadditionalerectionbracingisrequired,theerectionbracingplanwithspecifiedbracingdetailswillbeincorporatedintotheerectionplanforthestructure.Thedesignanalysisanddetailswillbesealedbytheprecastdesignprofessional.
Internalpreconstructionmeetingsbetweentheerectionforemanandtheprecastdesignprofessionalsandon-sitepreconstructionmeetingsbetweentheGeneralContractor,InspectionAgencies,andtheEngineerofRecord,areheldtoensurethatallaspectsofprecasterectionarefullyunderstoodandagreedupon.Thisincludesin-depthdiscussionsonprecastconnectionsandrequirederectionbracing.
Apre-erectionsurveyoftheCIPconcreteorsteelsubstructuresupportingtheprecastiscompletedwellinadvanceoferectionsoanyrequiredmodificationsorrepairstotheCIPorsteelcanbeaccomplishedwithoutaffectingtheerectionstartdate.ErectioncommencesonlyafterassurancefromtheEngineerofRecordthattheCIPhasachievedrequiredstrengthorthesteelstructureisreadytoacceptprecast.
Theerectorisrequiredtodevelopasite-specificSafetyPlanforeachproject.Thisplancontainsacompletehazardanalysisandfallprotectionplanningfortheproject.Priortostartoftheerection,theerectioncrewisfullybriefedontheSafetyPlanandunderstandsthesafetyconstraintsoftheproject.Thisincludeshandlingofthetypesofprecastproductsfortheproject.Allprecastdeliveredtotheprojectarriveswithashippingandhandlingtagattached.Thistagoutlinesthespecifiedmethodoferectingthepanelandgivesanyspecialhandlinginstructionsforrotatingorrollingtheprecast.Weeklyfollow-upsafetymeetingssometimesreferredtoas“ToolBoxTalks,”areheldonsiteforthedurationoftheproject.
Duringerectionoftheprecast,theerectionforemanisresponsibleforsafetyontheproject.TheforemancontinuallyobservestheworkofthecrewtoensurecompliancewiththepublishedSafetyPlan.PropersafetymarkingofthesiteismaintainedinaccordancewiththeSafetyPlanandtheforemanensuresthatnon-erectionpersonnelremainoutsidetheerectionarea.Onlywhentheproperlydocumentedturnoveroftheerectedstructurehasbeencompletedwillnon-erectionpersonnelbeallowedtoperformworkonthestructure.
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JohnPaulJonesArenaParkingStructure,UniversityofVirginia,Charlottesville,VA
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Bay SizeTheShockeyPrecastGroup’s48’baymoduleuses12’widedoubletees,whichresultinthemostcost-effectiveuseofprecastcomponents.Basedonthe12’doubleteewidth,thishandbookwillofferapossible“typical”parkingstructurelayout.Wheneverpossible,limittheuseofnon-standardteewidthsorbaysizes,asthiswillinfluencethecost.Thebaysizeyouchoosemayresultinverydifferentspandreldimensions,floortofloorheights,drainageplansand/orsupportingwallsystems.
DrainageForownersanddesigners,assuranceofaproperdrainagesystemisoneofthemostimportantconsiderationsinthedesignofaparkingdeck–bothforthehealthandlifeofthedeckaswellasforthecomfortandconvenienceofitspatrons.Theuseofa“drysystem”forwashesthatdirectwatertowardthedrainisconsideredsuperiortotheuseofCIPconcretepourstrips.WhileCIPtoppings,suchasthoseusedinpourstrips,typicallyfeaturea3,000psiconcretemix,theconcreteusedforaprecastdrysystemwillusea6,000psimix.Sincetheprecastdrysystemisproducedinacontrolledplantenvironment,itismonitoredbythePCIQualityControlprogram.ThequalityofCIPwashcastingsmaynotbecontrolledinthesamemanner.
Designedcorrectly,aneffectivedrainageplanwillhelppreventwaterfrompondingorcausingprematuredegradationtothejointinterfaces.Generally,drainsarelocatedattheinteriorbays,atalternatinggridlines.Oneeconomicalwaytoprovideproperdeckdrainageisto“warp”thedecksurface.Warpingoccurswhenthedeckperimeterisheldataconstantelevationandtheinteriorbaysarealternatelyraisedandlowered.Warpingisgenerallynotcauseforconcernregardingcrackingofthedoubleteesurface,providedthewarpisheldtoalimitof.175inchperfootofwidthfora60’longtee.PleasereferencePCIJournalJanuary/February2003,page35forstandardindustrypractice.Thefollowingdiagramprovidesanillustrationofthisconcept.
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48’ BAY SYSTEM
12 48’ BAY TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
Whilewarpingofthedecksurfaceisanoptionworthconsidering,itisalsopossibletoalternatelyraiseandlowertheperimeterofthedeckequallywiththeinteriorbays,resultinginatwo-waydeckcrossslope.Thiseliminatestheneedforwarpingteesbut,inturn,tendstobelesscosteffective.Theamountofcrossslopealongthelengthoftheteewilldependonthedecksystemandbaysizechosen.Eitheroptionispossibleandmayormaynotbesuitabletothedesigninquestion.
Afewimportantdrainagefacts-• TheShockeyPrecastGroupcastspre-manufactureddrainunitsintotheflangesof
thedoubleteesthatprovidecosteconomyandbettersealingqualitycomparedtofieldinstalledvarietiesandeliminatesfieldcuttingandinstallation.
• TheShockeyPrecastGroup’s“totalprecast”decksurfacedoesnotrelyontheuseoffieldtoppedCIPconcrete.Thisrepresentsasubstantialadvantageoverotherprecastsystemsandprovidesbetterdurabilityandlowercosts.Italsominimizesthechanceforwaterinfiltrationattheprecastinterface.
• TheShockeyPrecastGroupcandivertwatertowardthedrainusingoneofthreepossiblesystems:precastcurbs,monolithicprecastwashes,orCIPwashes.
• Locatinghandicappedparkingspacesshouldincludeconsiderationofmaximumallowableslope.
Drainage ConsiderationsThemovementofwaterfromthedecksurfaceisillustratedbelow.Theslopingofthedeckstructureenablesthewatertobedirectedtostrategicallylocateddrains.Thisslopinghasaverysignificanteffectonstructureframing.Therefore,earlydeterminationiscriticalandvitaltofloorheights.
High point Bay
width High point
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Concept of Warping
Expansion JointsUndernormalseasonalheatingandcoolingcycles,concretewillexpandandcontract.Thisinturngeneratesin-planeforcesanddisplacementsthatmustbeaccountedfor.Expansionjoints,whencorrectlylocated,allowtheseeffectstooccurwithoutadverselyaffectingtheprecastjointsandconnections.Dependingonthedeckconfiguration,expansionjointsshouldbelocatedamaximumof300feetapart.Theexpansionjointisfrequentlylocatedatthejointbetweentwoteesatacolumngridlineandshouldbelargeenoughtoaccommodatethecombinedthermalmovementoneachhalfofthestructure.Thelocationoftheshearresistingelementsalsoplaysaroleindeterminingthelocationofexpansionjoints.If,forexample,a300’longdeckcontainedstiff,shear-resistingelementsonbothends,itmightbeadvisabletointroduceanexpansionjointsomewhereinthemiddleofthedecktohelp“relieve”thebuildupofstressattheends.Thisisbecauseshearelementsactas“pointsoffixity”andwillacttorestrainthedeck,therebycausingconnectionforcestoexceedreasonablelimits.Itisessentialtorememberthatexpansionjointsalsoservetointerruptthelateralforceresistingsystem,which,forthepurposesofdesign,effectivelycreatestwoseparatebuildingstructures.Eachbuildinghalfmustcontainsufficientlateralloadresistingelements.
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Typical Framed Level Drainge Plan
14 48’ BAY TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
General LoadingAparkinggaragemustsatisfyavarietyofloadingrequirements.Inadditiontotheirownselfweight,parkinggaragesaredesignedtoresistuniformvehicularloadsof40psfortheapplicationofa3,000poundsactingonanareaof20squareinches(typicalsizeofthebaseofatirejack).Ifhigherloadingcriteriaareneededtoresistfiretrucksorotherlargevehicles,specialprovisionsmayberequired,includingthedeepeningofelementsortheadditionofreinforcing.Otherloadsincludewindorseismic,asdeterminedbytheapplicablebuildingcode.
Seismic/Wind ConsiderationsParkingstructurestypicallyutilizeshearwallstoresistthelateralwindorseismicforcesprescribedbylocalbuildingcodes.Dependingonlocationandsiteconditions,thedesignloadswillvary,aswillthenumberorsizeofshearwallsneeded.Shockeyengineersalwaysperformacomprehensivelateralloadanalysisofeachbuildingthecompanydesigns.LoadsfromthisanalysisarethengiventotheEngineerofRecordforverifyingtheCIPfootingandwalldesigns.
Whenpossible,itisadvantageoustoprovideshearwallslocatedalongthelineoframpwallswithanadditionalwalloneachendoftherampasshowninthefigurebelow.Anotheroption,dependingontheprescribedloads,istooffertheshearwallswith“punched”windowopeningstoprovideadditionallightandopenness.Horizontalrampwallscanbeusedtoprovidetherequiredlateralstabilityparalleltotheramp.Thesewallshaveopeningstoprovidelightandopenness.
Wallsshouldbelocatedinawaythattakesmaximumadvantageofthesurroundingdeadloadelements.Shearwallsthatsupportdoubleteesorinvertedteebeamswill“engage”moredeadload,whichhelpstocounteractthewalloverturningmoment.Whenoverturningmomentsarelargerthandeadloadresistingmoments,aconditionknownas“netuplift”onashearwallelementoccurs.Thisrequiresthedesignofhold-downdevicesorconnections,which,inturn,increasescost.
SincethedesignoftheCIPfootingsandwallsistheresponsibilityoftheEngineerofRecord,itisimportantthatsufficientthoughtbegiventoshearwallplacementearlyinthedesignprocess.TheShockeyPrecastGroupisableandqualifiedtoworkwiththeprojectengineerstohelpdeveloprational,economicalandpracticalload-resistingsystemsthatwillprovidesuperiorbuildingperformance.
Shea r walls
Possible
Stair shafts
Shear Wall Layout
Floor-to-Floor HeightThefloor-to-floorheightofaparkingstructuredependsonavarietyoffactors,includingtheprecastelementsusedandtheusagerequirementsoftheoccupants.Thesampleparkingstructureincludedinthishandbooksuggestsafloor-to-floorheightof10’-8.”Thisheightprovidesforoptimaleconomyandallowsaminimum7’-0”verticalclearanceundertheinvertedteebeams.
Fire ResistanceDependingonnumerousfactors,aparkingstructuremayberequiredtohaveeithera1-houror2-hourfirerating.MostparkingstructuresfallunderthecategorytypeIIB,asdefinedbytheInternationalBuildingCode,anddonotrequireanyparticularfireresistanceratingatall.However,whenrequiredbydesign,precastparkingstructurescaneasilybedesignedtoahigherleveloffireresistance.
Fireresistanceratingsofprecastcomponentsaremeasuredandspecifiedaccordingtothecommonstandard,ASTME119.Fireenduranceisdefinedastheperiodoftimeelapsedbeforeaprescribedconditionoffailureisreachedduringastandardfiretest.Designingprecastelementstosatisfyagivenfireresistanceratingwillincreasecoststosomedegree–primarilywhenadditionalreinforcingorlargermembersizesareneeded.
OpennessAprimarybenefitofthe48’bayisthattherearefewerverticalelementstointerruptthenaturalsightlines.Theinherentopennessofa48’bayparkingstructurecontributestoincreasedsecurityofparkingstructurepatronsandprovidesnaturalventilation.
Joints and RevealsJointsizesbetweenprecastandCIPelementsvary.Recommendednominaljointdimensionsarenotedinthishandbook.Thesejointshavebeenestablishedbasedontolerancerequirements(seesectionbelow),andtoensurealong-lastingjointinterface.
Whendiscussingthesejoints,itisimportanttounderstandthatthedimensionsgivenare
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1”
Tra pezoidal
Reveal
Color #1
Color #2
Joints and Reveals
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“nominal”–meaningactualjointsizesareallowedtodeviatefromthesevaluestowithinindustryacceptedranges,asdescribedinPCIMNL135.Whenselectingaccentrevealsorrusticationlines,itisimportanttotiethemtothechosenjointsize.Avoidtriangularrevealswherepossiblebecausetheyaredifficulttoaffixtotheforms.Instead,atrapezoidalrevealwillprovideaflatnailingsurfacefortheformbuildersandhelpminimizepossiblenailholeirregularities.Whenchoosingarevealsize,considerlimitingthedepthto¾”.Deeperrevealsdecreasetheeffectivesectionofthepanel.Thisreducespanelstrengthandincreasesthechanceforpanelcracking,whichmayrequireanincreaseinthepanelthickness.Besuretoincluderevealsbetweenanyandallcolorbreaks--whentwoseparatefacemixesareusedwithinthesamepanel,it’sstronglyrecommendedthatdesignersincludearevealbetweenthetwomixestoprovidethecastingcrewadistinctstoppingpointandhelpreducecolorbleed.Thiswillhelpensureasmoothbreaklinebetweenthetwocolors,asillustratedinthefigurebelow.
Corners and QuirksWhenconsideringdetailsatbuildingcorners,it’srecommendedthata¾”quirkbeintroducedatpanelreturns–especiallythoseexceeding1’-1”inlength.Toachieveasuperiorfinishalongthepanelface,panelsareoftenproducedintwophases,whichresultsinacastingorpourlinebetweenthetwopieces(seesketchbelow).Thequirkwillminimizethiseffectbyessentiallyhidingthelineintheapexofthenotch.
Corners and Quirks
Panel Corner Detail –
(Monolithic Pour)
Panel Corner Detail –
(Sequential Pour)
Maximum panel
return length = + 1’
1”
Square corner possible
but not recommended –
use quirk if possible
Pane 1 returns
greater than 1’ - 1”
quirk¾” quirk
First pour
Second pour
Sequential
pour line
Facial ProjectionsFacialprojectionscanaddauniqueaccenttoyourbuildingproject.Becausethesefeaturesarecasttothepanels“bottominform”,aminimumdraftdimensionisnecessaryinordertobeabletostripthepanelsoutoftheforms.Withoutproperdraft,suctionforcesgeneratedbetweentheconcreteandtheformmaycausethepanelstobindupduringstrippingandpossiblydamagethepaneland/orforms.Toensurethisdoesnotoccur,Shockeyrecommendsaminimumdraftof1:6onfacialprojections,asnotedinthesketchbelow.Alsokeepinmindthatfacialprojectionsincreaseproductioncosts,sinceformsneedtobebuiltuptoaccommodatethefeature.
TolerancesPrecastconnectionsandpaneldimensionsneedtoallowforindustrystandardtolerances.AnexcellentguidetoprecasttolerancesisavailablethroughPCI.TheToleranceManual,MNL135,describesindetailtheallowableproductionanderectiontolerancesforvariousprecastelements.Requestacopyatwww.shockeyprecast.com.
PenetrationsVerticalpenetrationsthroughthedoubleteeflangescanbelocatedanywhereexceptinthestem.Penetrationsthroughtheprecastthatmayberequiredforwallhydrants,pipepenetrationsandlightfixturescanbecastintothepanelsprovidedthecoordinationforlocationandsizeisdoneearlyenoughintheshopdrawingdevelopment.ThelocationandsizeofthesepenetrationsshouldbefurnishedtoShockeyduringtheshopdrawingprocess.Thisistoensurethattheinformationcanbeincorporatedintotheshopdrawingsandfabricationdrawingsinadequatetime.Foropeningslessthan10”square,itisrecommendedthatthepenetrationsbefieldcut.
ConnectionsDesignoftheconnectionsisalwaystheresponsibilityoftheprecaster.Shockeyutilizesavarietyof“user-friendly,”safeandefficientconnectionsthatallowprecastelementstobesetandsecuredinatimelyfashion.Includedinthishandbookareanumberoftypical
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Facial Projections
Panel as-cast
Forms built up to create
facial projections
Loops for stripping
Panel in final
erected position
Facial projection
6
1
Minimum draft
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connectionswhichprovidethedesignerwithasolidbasisforcosteffectiveandhighlyefficientdesigns.Dependingonvariousfactors,includinglifeexpectancyanddurabilityrequirements,embedmentfinisheswillvaryfromjobtojob.TheShockeyPrecastGrouptypicallyrecommendsthefollowingplatefinishes:
• Non-weldedplateconnectionsexposed Hot-dippedgalvanized totheelements or‘J’Finish
• Weldedplateconnectionsexposed ZincRichCold totheelements GalvanizingCoated
• RodsandBolts Electroplated
• Allothermaterial Plain
• Flange-to-flangeshearconnections Stainlesssteel
MaintenanceEnsuringlong-lastingdurabilityofaparkingstructurerequiresownerstakethenecessarystepstomaintainthestructureoncecompleted.Properlymaintainingaparkingstructurenecessitatesregularinspectionsandcleaningoftheprecastjoints,andarangeofotheritems.Theissueofsnowremovalshouldbeaddressedearlyinthedesignphasewithownerssoitdoesnotbecomeasourceofconcernoncethesnowplowsbegintheirwork.Forexample,theimpropermoundingorremovalofsnowcancauseadegradationofthejointsorteesurfaces.
CIP ConcreteCIPconcreteistypicallynotincludedintheprecastscopeofwork.However,sinceCIPinterfaceswiththeprecastelements,thecoordinationofprecasttoCIPinterfaceisextremelyimportant.CIPelevationsanddetailsshouldcloselymatchtheprecastdesigntoensuretheproperfit-upandexecutionofthepieceswhentheyarriveonsite.
Followingisanexplanationofeachdesignteammember’sresponsibilitiesregardingthecoordinationofCIP-to-precastinterface:
• Engineer of Record (EOR) –TheEORshouldspecifytopofCIPpier,wallandfootingelevationsandprovideadequatereinforcingdetailsoftheseelementswithinthecontractdocuments.Pierandfootingdesignsshouldaccountforthepossibilityofupliftandslidingforcesatshearwalllocations.Reinforcingdetailsshouldspecifyadequateconfinementsteelatthetopsofpiersandwalls,asrequiredbytheACIcode.Pierandwallsizesshouldtypicallybealargerdimensionthantheprecasttheysupportsothatanchorboltsandembeddedplatescanbeeasilyplacedwithintheconfinementsteel.DowelsoranchorboltsusedtoconnecttheprecasttotheCIParetypicallytheresponsibilityoftheprecaster.Inmanycases,TheShockeyPrecastGroupmaysuggestalternatetopofpierorfootingelevationsthateitherenhancethestructure’sperformanceorimprovecost-effectiveness.Inthiscase,theCIPsubcontractorisaskedtoexecutethedetailsaccordingtotheprecastdrawings,sincethisishowthepiecesarefabricated.
• General Contractor (GC)–CoordinatetopofCIPpierandwallelevationswiththestructuralandprecastdrawings.EnsurethattheCIPsubcontractorfollowsandproperlyexecutesthereinforcingdetailsthatareshownontheContractDrawings(seenotesabove).
• The Shockey Precast Group–DesignandprepareanchorboltlayoutdrawingsforusebytheGCandCIPsubcontractor.SupplyallloosehardwareandanchorboltsneededfortheattachmentoftheprecastelementstotheCIPconcrete.
• CIP Subcontractor–CarefullyexecutetheCIPreinforcinglayoutsperthestructuraldrawings,includingtheconfinementtieslocatednearthetopsofpiersandwalls.Incorporateloosehardwarefortheprecastconnectionsaccordingtothelocationsshownontheprecastlayoutdrawings.WhenadiscrepancyexistsbetweenthestructuraldrawingsandtheprecastdrawingsfortopofCIPelevations,theprecastdrawingsgovern.
ThefollowingsketchillustratestheCIP-to-precastinterface:
ItisgenerallyrecommendedthattheCIPsystembedesignedsuchthattheprecastelementsarenotrequiredtoretainearthloads.Instead,CIPretainingwallscanbeprovidedthatactindependentlyfromtheprecasttowithstandtheseforces.Ifnecessary,itispossibletodesigntheprecastteesorwallsbelowgradetoacttoresistearthloads,asshowninthefollowingsketch.Thiscouldinfluencethelocationofshearresistingelements,connections,andmaynecessitatetheuseofacast-in-placetoppingonthetees.
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Reinforcing including ACI required
confinement ties to be designed and
detailed by the EOR, furnished and
installed by the GC or CIP subcontractor
Anchor bolts or embedded plates
supplied by Shockey, installed by
CIP subcontractor at locations
shown on precast anchor bolt layouts
Always maintain top of pier or wall
elevations as shown on the precast
drawings. Notify GC of any
discrepancies between the structural
and precast drawings
Ideally, the CIP section should be
wider than the supported precast.
For piers, this should be 2” on all
sides. For walls, 1” is suggested
CIP Pier for Precast Column
Free-Standing Wall Fixed Wall
Free standing, CIP retaining wall.
Backfill wall and allow for
anticipated wall movement or
rotation to occur prior to setting precast .
Precast double tee
Precast double tee
CIP or precast retaining wall.
Possible CIP topping
Connection
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The 48’ Bay SystemToillustratethetypicalpaththatTheShockeyPrecastGroup’sdesign-assisteffortwouldtake,pleaseconsiderthefollowingexample:
TheShockeyPrecastGroupisapproachedbyapotentialcustomer,whobringstothetablethisinformationregardingaparkingstructure:
1. Thestructuremusthaveafloor-to-floorheightof11’8”gradetofirstelevated level,and10’8”onallotherlevels.
2. Rampslopeis6.1%atthefirstlevel,and5.6%attheupperlevels.
3. The256,000SFstructuremustbedesignedtoaccommodate790cars.
Usingthisinformation,TheShockeyPrecastGroupwillworkwiththedesignteamtoachieveanoptimallayoutusingthe12’doubleteesand48’baysystem.Onthefollowingpageisanexampleofowner-providedsketchestypicallyreceivedbyTheShockeyPrecastGroupatthebeginningofthedesign-assistprocess:
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Usingtheowner-providedsketchesandbasicdeckrequirementsasaguide,TheShockeyPrecastGroupworkswiththeprojectdesignteamtodevelopacustomized48’baysolutionthatmeetstheowner’sneedsandsatisfiesthedesigner’svision.Specificsofthedeckarelistedbelow:
Deck Type
12’wide,30”deeptees 48’widebays 10’-8”floortofloorheight 7’-0”minfreeverticalclearance 192’longrampwitha5.55%slope 177parkingspacespertypicallevel
ThefollowingpagesillustratethetypicalprecastcomponentsandconnectionsthatcompriseTheShockeyPrecastGroup’s48’baysystem.Thesedetailsareincludedtogivethedesignerabetterunderstandingofthe48’baymoduleasawhole,andtogiveinsightastonecessarydesignconsiderationsspecifictoprecastconcreteparkingstructures.
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Results: Floor Framing Plans and Parking Layout Plans
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South Building Elevation (Highlightingproductdescription)
North Building Elevation (Highlightingproductdescription)
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East Building Elevation (Highlightingproductdescription)
West Building Elevation (Highlightingproductdescription)
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West Elevation at Stairwall (Highlightingstairwallcutaway)
Longitudinal Building Cross Section at Ramp walls
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Building Cut-Away Section Illustrating Building Assembly
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Pocketed Shear Wall Details
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Horizontal Ramp Wall and Details
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Vertical Ramp Wall Options
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12’ Wide Double Tee Profile W/6’-0” Stem Spacing
12’ Wide Double Tee Profile W/5’-0” Stem Spacing
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Inverted Tee Beam Profile Detail
Deck Drain Details
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Stem Block-Out Details
Double Tee to Flange Chord Connections
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Column to CIP Footing or Pier
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Double Tee to Spandrel Connection Details
Double Tee to Spandrel Details Corbel Detail
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Double Tee to Spandrel Connection Details Top Connection
Double Tee to Beam Connection Details
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Non-Load Bearing Spandrel to Column Connection
Load-Bearing Spandrel to Column Connection
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Outboard Column Option
TheShockeyPrecastGroup’s48’baymoduleoffersincomparableefficiencyandcost-effectivenessfortheowner.Thefollowingchapterhighlightstheflexibilityandfreedomavailabletothedesignerthroughthe48’baymodule.
PARKING STRUCTURE AESTHETICSThedaysofplain,gray,box-likeparkingstructuresareover.Savvyownersanddesignersaretakingadvantageofthenearlylimitlessdesignfreedomofferedbyprecastconcrete.AtShockey,wehelpourcustomersrealizetheiruniqueprojectvisionswithindividualizedprecastsolutionsthataredurable,costeffectiveandbeautiful.Inthischapter,wewillexplorethevarietyoffinishoptionsavailablewithprecastconcretefromShockey.
Color, Textures and Applied FinishesThroughavarietyofaggregates,choiceofmatrixcolors,varyingdepthsofexposure,andfinishingtechniques,precastcanmeetalmostanycolor,formortexturethatmaybespecifiedbythedesigner.Additionally,thebeautyofnaturalaggregatesisgreatlyaccentuatedwhentheaggregatesarefusedwiththecolorandtexturebenefitsofprecast.
ColorTheShockeyPrecastGrouprecommendsthatcolorselectionsbemadeinthesameorsimilarlightingconditionsasthefinal,in-placeconditions.Inordertomaintainmatrixcoloruniformity,whitecementshouldalwaysbeusedalongwithcolorpigmentsconformingtoASTMC979.Evenwhenthedesiredmatrixcolorisgray,theuseofwhitecementandgraypigmentisstillhighlyrecommended.
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Whenreviewingcostinselections,itisimportanttoconsiderthesourceofaggregateifdeepexposureisrequired(localsourcesarealmostalwaysmorecosteffective);andtorealizethatmatrixcolorssuchasblueandgreenarehighercostselections.
Variationsincolorcanbeachievedwithinareasofthestructureorwithineachindividualprecastunit.Useofmultiplecolorsrequiresclearlydefinedcolorbreaks,whichcanbeachievedwithreveals,jointsandprofilechangestoensurecrisptransitions.
Deepexposurefinishescanbeachievedeitherthroughtheuseofchemicalretardantsorthroughthesand-blastingprocess.Inbothcases,morethanjusttheextremesurfaceareaoftheaggregateisexposed,allowingthecoarsestoneaggregatetoprojectbeyondthecementmatrix.Theexposureshouldremainat40%ofthenarrowdiameterofthecoarseaggregateinordertopreventtheoccurrenceof“baldspots.”Bothtypesofsurfacetreatmentshighlightthenaturalbeautyofthestonewhileprovidingatexturethatcannotbeobtainedthroughtheuseoflighterfinishingtechniques.
TextureTextureexpressesthenaturalbeautyofthematerialcomponentsandcanbeusedtodefineoraccentuatespecificareasofthestructure’sfaçade.Texturetakesadvantageofitschangingrelationshiptolighttocreatearangeofsurfacedifferencesfromsubtletodramatic.Whenchangingtexturesorexposureswithinasingleprecastunit,clearandwell-definedbreakpointsareneededsimilartothoseforcolor.Texturedsurfacesalsohavetheaddedbenefitofhidingtheeffectsofweatheringandhigh-volumeuseareassincetheirregularitiesinthesurfacehelpdivertattentionfromlinestreakinganddiminishtrafficusemarks.
Texturecanbeachievedthroughavarietyofdifferenttechniques,andcanrangefromlightexposuretodeepexposure.
Applied FinishesTheseareavarietyofpost-appliedtechniquesusedtoachievethedesiredappearanceandcharacterofthefaçade.Thestructure’sfinalappearanceisobtainedthroughthecombinationofmixdesignselectionandthechoiceofappliedfinish.Althoughfinalfinishessuchasbrickveneersarecastinnaturalstoneorformliners,andmayreceiveapost-castingfinish,theyareaddressedseparatelysincethecriticalelementsofobtainingthedesiredappearanceareachievedduringthepre-pouroperation.
Thedepthoftheappliedfinishshouldtakeintoaccountthesize,function,articulationandconfigurationoftheunits.Finalselectionofthefinishgradationshouldbemadeduringthemock-upphaseandshouldincluderecommendationsfromTheShockeyPrecastGroup.Variationofappliedfinisheswithintheindividualunitscanbeusedtoenhancetheoverallappearanceofthestructure.Thiscanbeamorecost-effectivemeansofaccentuatingkeycomponentsorareasofthefaçadethantheuseofmultiplemixes.Whenmultipleappliedfinishesarepartofthedesign,thesamelogicregardingprofilechangesand/orrevealworktoensurecleanbreaksshouldbeappliedasthatofmultiplemixes.
Acid Etch FinishAcidetchingisaprocessthatdissolvesthesurfacecementmatrixtoexposethesandand,toalesserextent,thecoarseaggregate.Acidetchingistypicallyusedtoachievealight-to-medium-lightexposure.Theendresultissimilartothatofnaturalproductssuchas
sandstoneorlimestone.Theetchingprocessleavesasugar-cubeappearance,whichisenhancedbydirectsunlight.
Thedecisiontoincorporateanacid-etchfinishmustbemadepriortoorduringthemixdesignprocesssinceonlyacid-resistancesiliceousaggregates(granite,quartz,etc.)shouldbeused.Carbonateaggregatessuchasdolomiteandlimestone,suitableforsandblastingmixes,willdissolveordiscolorthroughtheacid-etchingprocessduetotheircalciumcontent.Complementaryaggregates(fineandcoarse)andcementpigmentsshouldalwaysbechosenwhenanacidetchfinishisselected.
Acidetchingisthecrucialsecond-stepprocesswhenthefaçadeofthestructurewillincludeclayproductssuchasthinbrickveneer.Thisprocessnotonlyhelpsremovesomeofthesurfacelaitanceonthebrickduringthemanufacturingprocess,butalsoexposesthesandbetweenthethinbrickjointstomimicthatofhand-laidbrickmortar.Itisusedasasafefinisharoundthebrickveneerforincorporatedprecastfeaturessuchaslintels,sills,bands,andprojectionsthathaveallbeenintegratedwithinthesameprecastunit.
Sand-Blasted FinishSandblastisthegenerictermusedfortheabrasiveblastingprocess.Varyinggradationsofblastmaterialareusedtochipawaytheprecastsurface.Selectionofaparticulargradationdependsonthedesireddepthoffinish.Sandblastingallowsthedesignerthefullrangeofdepthsobtainableinprecast(lighttoheavy).Onfinalexposedsurfaces,brushblastingshouldbeavoidedbecauseofitsinabilitytouniformlyremoveallthesurfacelaitance.Lightblastingprovidesasimilarappearancetothatfoundinnaturallimestonewithoutthe“sugarcube”appearancecreatedbyacidetching.
Incontrasttoacidetching,blastingtendstobebettersuitedtomutingorcamouflagingminorvariationsthatoccurinthemanufacturingprocess.Thisisespeciallytruewhenaddressingdeepprofilearticulations.Deeperblastshaveanincreasedabilitytoensureuniformity.However,onceblastingexceedsthelightleveloffinishandtexture,theendresultismoredependentonthenaturalelementsofthemix(aggregates).Complementaryaggregatesandmatricesshouldalwaysbeconsideredwhenspecifyingdeeperlevelsofexposure.Adeeperblastcanmimicothernaturalmaterialssuchasflamedgraniteandcancreateinterestingplaysoflightthroughitstexture.
Blastingcanalsobeamoreeconomicalmeansofachievingmultiplevariationswithinthesameunitthanincorporatingmultiplemixdesigns.Blastingcreatesmultiplevariationsbyexposingdifferinglevelsofthecoarseaggregateinpre-definedareasoneachpanel.Theoveralldesiredeffectoftextureisalsoinfluencedbythetypeandselectionofcoarseaggregateinrelationtothepsiofthematrix.Softeraggregateswillbecomeconcaveduringtheblastingprocess,whileharderaggregateswillbecomeconvex,dependinguponthedepthofexposure.
Exposed AggregateThisprocessisachievedbychemicallyretardingthematrix,whichprovidesanon-abrasivemethodofexposingthenaturalbeautyofthecoarseaggregates.Unlikethesandblastingprocess,thechemicalretarderdoesnotmuteordamagethecoarseaggregates.Thechemicalretarderisappliedtothemoldsurface,whichdelaysthecementpastefromsettingup.Afterstrippingthepanel,theretardedoutersurfacelayerofcementisremovedwitha
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high-pressurewasher.Avarietyofdepths,fromshallowtodeep,canbeachieveddependingonthetypeofretarderused.Aswithotherfinishes,variationsofexposurewithinthesameunitcanbeachievedwithchemicalretarders;however,aclearrevealorprofilechangeisamustforthetransitionpointstopreventbleedingofexposure.Thechoiceofaggregatesizeisessentialwhenchoosingdepthtopreventexcessiveaggregateloss“baldspots.”Iftheownerordesigner’svisionistoenhancethebright,naturalcolorsoftheaggregates,chemicalretardersshouldbeused.Itisrecommendedthatcontrastingmatricesandaggregatesbeavoidedtopreventa“patchy”appearance.
Form LinersFormlinersofferthedesignerawidearrayofpossibilitiesinshapes,patterns,textures,anddesigns.Thelinermaterialuseddependsonthedesiredeffectandthenumberas-castrequired.Anycombinationofappliedfinishescanbeutilizedinconjunctionwithformliners.Formlinerfinishescanbeimplementedeitherasthemainaestheticfeatureorasahighlight,medallion,orlogo.Advancesinformlinertechnologieshavecreatedadesignpalettelimitedonlybytheimagination.Whenvastareasofprecastwilluseformliners,limitationsoflinersizesshouldbeincorporatedwithrevealworktopreventlinerbuttjoints.Formlinersprovidethehighestdegreeoftextureandwillenhancetheplayoflightandshadows,creatingachangingappearanceofthefaçadethroughouttheday.Keyplacementofnightilluminationcanalsocomplementtheeffectsoftheliner.
Formlinersareakeycomponentwhenimplementingathinbrickveneer.Thethreemaintypesofbrickliners(elastomeric,plasticgrids,andsnaps)eachhavetheirownpositiveattributes,dependingonprojectdesignandpanelconfiguration.TheselectionofalinershouldbemadewiththeguidanceofTheShockeyPrecastGroup.Whenadesignerchoosestouseaformliner,itisveryimportantthatthedesignerrecognizetheleadtimerequiredwithformliners.Leadtimewillvarybytypeoflinerandpatternselected.Linersrequiringuniqueartworkwillrequireadditionaltimefortheartisantocreatethemastermold.
Formlinerleadtimescanrangefrombetweenfourtoeightweeks.Whenelastomericlinersareusedinconjunctionwiththinbrick,asamplerunoftheactualbrickbeingusedisrequiredinordertoobtainthecorrect“fit.”Thefirst100bricksfromarunaremeasuredandtheformlinerisbasedontheaveragebricksize.Inadditiontotheleadtimefortheformliner,theleadtimerequiredonthebrickmustbeconsideredaswell.Brickmanufacturerswillusuallyfabricatethelightershadesinthebeginningofthemonthandthedarkershadesattheend(orviceversa).Dependingonthetimeofthemonthandthetypeandcolorofthebrickselected,itistypicallyfourweeksminimumuntilthefirstrunofbricksisdelivered.
Case StudiesInthissection,wefeaturecurrentexamplesofprojectsthatbenefitedfromTheShockeyPrecastGroup’sdesign-buildcapabilities.Eachoftheseprojectsoffereditsownchallenges,includingaggressiveschedule,complexdesign,tightbudget,andlimitedsiteaccess.Theuseofprecastconcretecontributedsignificantlytotheoverallsuccessofeachoftheseprojects.
Calvert Street Parking Structure, Annapolis, MD
TheCalvertStreetParkingGarageinhistoricdowntownAnnapolis,Marylandisa168,000SFparkingstructureownedbytheDepartmentofGeneralServicesoftheStateofMaryland.Designofthestructurecalledforfourbaysoffourlevelsofelevatedprecastframing,consistingoftworampedbaysandtwoflatbays,providing727parkingspaces.Exterioraestheticswereofparamountconcerntotheownerthroughoutthedurationoftheprojectgiventhecloseproximityofthenewstructuretoseveralhistoricalbrick-cladbuildingsoftheStateCapitolcomplex.TheShockeyPrecastGroupmetthisdesiredintentbyprovidingastructuralgrayprecastframesurroundedbyaseparatefaçadeofarchitecturalprecastusingamixofhighlyarticulatedthin-brickandarchitecturalprecastelements.Thearchitecturalfaçadewasessentiallyself-supportingwithregardtogravityload,withrequiredlateralsupportprovidedbytiebacktothestructuralframe.Inordertoensureasuccessfulproject,thedesignteamhadtobevigilantindetailingthenumerousinterface/offsetconditionsandconnectionschemessuchthatrequirementsforconstructabilityandaccesswereinconcurrencewithaestheticrequirements.
TheShockeyPrecastGroup’sWinchesterproductionfacilityprovided554piecesofstructuralprecastfortheproject,includingdoubletees,beams,columns,spandrels,verticalrampwalls,shearwalls,flatslabs,andstair/elevatorcorewalls.The223elementsofthearchitecturalfaçadewereprovidedbyTheShockeyPrecastGroup’sFredericksburgproductionfacilityandconsistedofanarrayofspandrels,wallpanels,cornices,coping,andcolumncovers.
ThedesignofthefaçadespecifiedtwocolorsofthinbricktobeusedineitherstandardrunningorFlemishbondcoursingatspecificlocationsalongtheexteriorelevations.Layoutanddetailingofthehorizontalandverticalcoursingofbrickpresentedaformidablechallengetoallmembersofthedesignandproductionteam,thusrequiringdiligentattentiontoassureproperalignmentofbrickbetweenprecastelements.Thepresenceofseveralhighlyarticulated,ornatecorniceandsilldetailsofarchitecturalprecastpresentedachallengetobothdesignandproductionteams.Inordertoaccenttheprecastfaçade,numerouspiecesofdecorativesteelcolumns,channels,beams,grilles,andglazingwerefield-installed.
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Erectionofthestructurewasextremelydifficultduetolimitedaccesstotheinteriorfootprintofthestructure.Thearchitecturalfaçadehadtobeerectedinconjunctionwiththestructuralcomponentsoftheparkingstructure.Theaccessplanwaschangedtoeliminaterampconstruction,andthelastphaseofconstructionwasmovedtothetopofBladenStreetoutofthefootprint.Thischangesavedtimeandexpenseforthegeneralcontractor,andresultedinashorterandmorecontinuouserectionprocess.Erectionwascompletedonscheduleinapproximately12weeks.
Project Timeline:
Design July2005–December2005Construction December2005–February2007ProductionWinchester January9,2006–May16,2006ProductionFredericksburg January3,2006–May17,2006PrecastErectionStart April3,2006ErectionComplete July21,2006OpentoPublic January10,2007
D.C. Nationals Parking Structures, Washington, DC
Thisprojectincludedtwoparkingstructuresthatwouldprovide1,250parkingspacestoD.C.Nationals’patrons.Bothgarageswerescheduledtobebuiltduringconstructionofthenewbaseballstadium,NationalsPark.Theoriginalconceptspecifiedanundergroundparkinggarage;however,complicationsinthedesignprocessmadethisconceptimpractical.
Withonly12monthsremainingintheprojectschedule,theprojectwasredesignedasaprecastparkingstructureandTheShockeyPrecastGroupwasrecruitedasadesign-buildpartner.Shockeyassistedtheteamwithdevelopmentoftheoveralllayoutofthegaragessothattheowner’sconstructioncompletiondeadlineofApril2008couldbemet.On-timecompletionwasessential,asApril2008markedthestartofthe2008baseballseasonandopeningdayoftheNationals’newstadium.
Thesiteitselfpresentedsignificantchallenges.TheDCNationalsBallparkissetbelowgradeelevation,soitwasnecessarytoincludearetainingwallbetweentheballparkandthegaragesinthedesignoftheparkingstructures.InordertomeetLEEDrequirements,thedesignerhadtoallowforadditionalprogramfeatures,suchasbicycleparking,inthedesign.Parkingaccesscontrolswerealsoincludedtoaccommodatethefuturepossibilityofcommercialuseofthegaragesbytheowner.
TheShockeyPrecastGroupproducedatotalof308,000squarefeetofprecastdoubleteesfortheproject.Bothgaragesconsistofthreeframedlevelsandarethreebayswide.TheEastgaragefeatures170,000squarefeetofdoubleteesandtheWestgarageincludes138,000squarefeetofdoubletees.DesigndevelopmentwasanongoingprocessandtheShockeyteam’scoordinationeffortsincludeddevelopmentofthedrawingsandmatchingtheparkingstructures’precastfinishestothoseoftheballpark.TheShockeyPrecastGrouphadtoallowforretailandticketsalesonthefirstfloorofbothparkingstructures.Sincetheseretailareashadcast-in-placeconcretearoundthem,itwasnecessaryforTheShockeyPrecastGroup
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58 PARKING STRUCTURE AESTHETICS TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
toincludecoordinationandinteractionwithCIPinitsplanninganddesign.Becauseofthesurroundingretailareas,thefirstfloorofthegarageswasunusuallytall,addingtothecoordinationconsiderationsincorporatedbythedesignteam.
Complexrevealsandtwodifferentsandblastpatternsincreasedtheoverallintensityoftheproject,buttheuseofarchitecturalprecastmadeitpossibleforthedesigner’svisiontoberealizedwellwithintheprojecttimelineandbudget.AnotheruniqueaspectoftheprojectforthedesignerandforTheShockeyPrecastGroupwasthattheprecastdesignhadtoaccommodatethehangingofartworkontheexteriorofthegarages.Theprecastshearwallswereincorporatedintotheexterior“windowdressing,”andatowereffectwasaddedtothefaçadetocreatevisualinterest.
ErectionoftheparkingstructuresbeganinJuly2007andwascompletedonNovember21,2007.ThefinishingofthestructureswascompletedonMarch1,2008.
Nationals Parking Structures Construction Timeline:
June6,2007 ProductionstartJuly23,2007 ErectionstartNovember21,2007 ErectionCompleteMarch1,2008 FinishingCompleteApril15,2008 Walk-throughwitharchitect
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60 PARKING STRUCTURE AESTHETICS TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
Gaylord National Harbor Resort and Convention Center
ThePetersonNationalHarborCenterisa300-acresitelocatedona1¼milewaterfrontstretchofthePotomacRiverinPrinceGeorge,Maryland.NationalHarborishometo7,000,000squarefeetofrestaurants,shopping,officespace,residencesandhotels,includingtheGaylordNationalHarborResortandConventionCenter.TheGaylordNationalHarborResortisthelargestnon-gaminghotelandconventioncenterontheeastcoastandthelargesthotelinWashingtonD.C.
Anumberofdifferentparkingstructureconfigurationswereconsideredinordertomaximizetheoptimalnumberofparkingspaces.Theapproveddesignspecifieda247,700SF,six-levelstructuretoprovide1,933parkingspacesforstaffandvisitorstotheGaylordNationalHarborResortandConventionCenter.TheupperfivelevelsoftheparkingstructurewereconstructedofprecastcomponentsproducedbyShockeyatitsFredericksburgandWinchesterplants.Shockeymanufacturedanderected12’x30”doubleteeswitha4”flange,12’x30⅝”doubleteeswitha4⅝”flange,8”flatslabs,10”thickwalls,stairunits,columnswitharchitecturalfinish,L-beams,24”x36”inverted-teebeams,10”thickprestressedspandrelswithanarchitecturalfinishand10”thickprestressedverticalrampwallsfor6’stems.
Theparkingstructure’sarchitecturalprecastfeaturesincludehorizontalribsonspandrelsandexteriorelevatorwallpanels,columncoversandaplanteronthenorthendofthegarageroof.TheexterioroftheparkingstructurerequiredarchitecturalmixdesignandfinishesbeconsistentwiththoseoftheHotelandConventionCenter.
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TheuseofprecastratherthanCIPconcreteenabledthebuildingtobeconstructedwithinitsownfootprint.TheproposedschedulewasveryrestrictiveregardingShockey’sactivitiesandscheduleduringtheconstructionprocess.TheuseofprecastallowedthemajorityoftheworktobeperformedatShockey’smanufacturingfacility,whichenabledShockeytomeettheschedule’srestraints.
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Products Used:
12’x30”DTwith4”flange12’x30⅝”DTwith4⅝”flangeColumnCovers8”precastflatslabs10”thickwallsPrecastStairUnitsColumnswithArchitecturalFinishL–Beams24”x36”PrestressedInvertedTeeBeam10”thickprestressedspandrelswitharchitecturalfinish10”thickprestressedverticalrampwallfor6’stems
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Long&FosterParkingStructure,Chantilly,VA
THE ALTUSGROUPC-GRID® Reinforced Double Tees for Parking StructuresTheShockeyPrecastGroupisamemberofAltusGroup,anationalpartnershipofprecastconcretemanufacturersandsuppliers.Committedtoinnovation,AltusGroupdevelopsandmarketsCarbonCastproductsmadeusingC-GRID®carbonfibergridreinforcing–includingprecastwallpanels(architecturalcladdingpanelsandhighperformanceinsulatedwallpanels)pretoppeddoubletees,andresidentialwallpanelsandstemdecks.LEED-friendlyCarbonCastproductscanweighless,insulatebetterandlastlongerthancompetitivebuildingtechnologies.
In2008,ShockeyembarkedonitsfirstCarbonCastproject:the$7.68millionWinchesterParkingStructure.The140,000square-foot,five-storyWinchesterParkingStructureissituatedatacornerinWinchester’shistoricdistrict.Theparkingstructurefeaturesabrickfaçade,accentedwithprecastconcretefeaturesthatmimiclimestone.Anenclosed,elevatedpedestrianwalkwaywillconnecttheparkingstructurewiththeFrederickCountyOfficeComplex.TheWinchesterParkingStructurefeatures482precastcomponents,including204precastdoubleteesreinforcedwithCarbonCastC-GRID®carbonfiber.TheuseofC-GRID®reinforceddoubleteesprovidedacost-effectivesolutionthatenabledtheprojecttostaywithinbudget,whiletheuseofprecastconcreteenabledtheteamtomeettheowner’sveryaggressiveschedule.TheShockeyPrecastGroup’sotherC-GRID®projectsincludeparkingstructuresforTheUniversityofMarylandatShadyGroveandWalterReedMedicalCenter.
Shockey’smembershipintheAltusGroupenablesustobringknowledgeofandexperiencewiththeindustry’slatestinnovationsandtechnologytoeveryoneofourparkingstructureprojects.Notonlycanweoffereconomic,attractiveparkingstructuresolutions,wealsousematerialsandsystemsthatcanresultingreaterparkingstructurelongevity,durability,andoverallstrength.
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TheShockeyPrecastGroup’sC-GRID®EmbedmentMachineplacesC-GRID®intoadoubleteefortheWinchesterParkingStructureproject.
64 THE ALTUSGROUP TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM THE ALTUSGROUP 65
These sections have been reprinted with permission from the Altus Group’s Carbon Cast Pretopped Precast
Double Tees brochure.
66 THE ALTUSGROUP TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
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WashingtonDCNationalsParkingStructures,Washington,DC
SECTION 03 41 00PRECAST STRUCTURAL CONCRETE
GUIDE SPECIFICATION
General
1.1 SUMMARY
A. Section includes:
1. Structuralprecastconcretefor: a. Columns b. Beams c. Spandrels d. FloorandRoofDoubleTees e. InvertedTeeBeam f. StairRiserSections g. WallPanels h. FlatSlabs i. ShearWalls 2. CaulkingandExpansionJoints 3. AccessoriesandSupportingDevices
B. Related Requirements:
1. Section034500-PrecastArchitecturalConcrete 2. Section079201–JointSealants
1.2 REFERENCES
A. American Concrete Institute:
1. ACI301-SpecificationsforStructuralConcrete 2. ACI318-BuildingCodeRequirementsforStructuralConcrete
B. ASTM International:
1. ASTMC33–StandardSpecificationforConcreteAggregates 2. ASTMA36/A36M-StandardSpecificationforCarbonStructuralSteel 3. ASTMC94–StandardSpecificationforReady-MixedConcrete 4. ASTME119-StandardTestMethodsforFireTestsofBuilding ConstructionandMaterials
T h e S h o c k e y P r e c a s t G r o u p
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5. ASTMC150-StandardSpecificationforPortlandCement 6. ASTMA153/A153M-StandardSpecificationforZincCoating(Hot-Dip)on
IronandSteelHardware 7. ASTMA185-StandardSpecificationforSteelWeldedWireFabric,Plain,for
ConcreteReinforcement 8. ASTMC260–StandardSpecificationforAir-EntrainingAdmixturesforConcrete 9. ASTMA416/A416M-StandardSpecificationforSteelStrand,Uncoated
Seven-WireforPrestressedConcrete 10. ASTMC494–StandardSpecificationforChemicalAdmixturesforConcrete 11. ASTMA497-StandardSpecificationforSteelWeldedWireFabric,Deformed,
forConcreteReinforcement 12. ASTMA615–StandardSpecificationforDeformedandPlainBillet-SteelBars
forConcreteReinforcement 13. ASTMC618–StandardSpecificationforCoalFlyAshandRaworCalcined
NaturalPozzolanforUseasaMineralAdmixtureinPortlandCementConcrete 14. ASTMA666-StandardSpecificationforAusteniticStainlessSteelSheet,Strip,
Plate,andFlatBar 15. ASTMA706/A706M-StandardSpecificationforLow-AlloySteelDeformed
andPlainBarsforConcreteReinforcement 16. ASTMC979–StandardSpecificationforPigmentsforIntegrally
ColoredConcrete 17. ASTMC989–StandardSpecificationforGroundGranulatedBlast-FurnaceSlag
forUseinConcreteandMortars 18. ASTMF1554–Grade36AnchorBolts
C. American Welding Society:
1. AWSD1.1-StructuralWeldingCode-Steel 2. AWSD1.4-StructuralWeldingCode-ReinforcingSteel 3. AWSD1.6–StructuralWeldingCode–StainlessSteel
D. Precast/Prestressed Concrete Institute:
1. PCIMNL-116-ManualforQualityControlforPlantsandProductionofStructuralPrecastConcreteProducts
2. PCIMNL-120-PCIDesignHandbook-PrecastandPrestressedConcrete 3. PCIMNL-123-DesignandTypicalDetailsofConnectionsforPrecastand
PrestressedConcrete 4. PCIMNL-127–PCICommitteeReport–Erectors’ManualStandardsand
GuidelinesfortheErectionofPrecastConcreteProducts 5. PCIMNL135–TolerancesforPrecastandPrestressedConcreteConstruction
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1.3 DEFINITIONS
A. Fabrication Drawings: Documentsusedbytheproductionfacilityto manufacturetheprecastcomponents.Sometimesreferredtoas“Shop Drawings.”Informationincluded: 1. Requireddimensionalinformation 2. Descriptionandlocationonallinserts,bearingplates,anchorsand
reinforcementmaterialsrequiredtomanufacture,transport,anderecttheprecastcomponent
3. Finishrequirementsforeachcomponent 4. Handling,storageandshippinginstructions 5. Providedasaninformationalsubmittalonly
B. Erection Drawings:Documentsprovidingtheassemblyplacementofprecast componentsonthejobsite.ErectionDrawingsarereviewedandsealedbya ProfessionalEngineer.Informationincluded: 1. Plansandelevationslocatinganddimensioningallprecastcomponents.
Eachprecastcomponentisindividuallyidentified. 2. Sectionsanddetailsshowingconnections,openings,blockouts,andcast-initems
andtheirrelationshiptothestructure. 3. Descriptionofalllooseandcast-inhardwareformakingconnections.
C. Construction Plan: Amanagementplanforthesequenceofassemblyoftheprecast componentsoftheproject.Thisplanincludes: 1. Accessplanforcraneandtransportofprecastcomponents. 2. Erectionsequencebyloadsbeingshipped. 3. Erectionblockplanoutliningthesequenceoferectionactivity. 4. Specificerectioncriteriarequiredfortheparticularproject. 5. Project-specificconstructionstabilityplanthatoutlinesanyadditionalerection bracingthatmayberequired. 6. Technicaldatasheetongroutusedfortheproject. 7. Erectiontolerancesfortheproject.
D. Field-Use Erection Drawings: Theerectiondrawingswithanymodificationsmade duringtheapprovalprocessthataredistributedpriortoactualerectionoftheproject.
E. Control Number:Auniqueidentificationofeachprecastcomponentforaproject.
F. Piece Mark:Acomponentidentificationofaprecastelementonaproject.Similar piecescanhavethesamePieceMarkbuteachwillhaveauniqueControlNumber.
G. CIP: Cast-in-Place Concrete
H. Architectural Features: Wherefinalappearanceorformofprecastcomponents requiretheuseofcoloredaggregate,pigmentedconcretemixorsurfacetexturessuch assandblasting,waterwash,etchedfinishesorthinbrick.
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I. BIF:“Bottominform”indicatesthesurfaceofprecastthatwillbeinthebottomofthe formduringcasting.
J. SIF:“Sideinform”indicatesthesurfaceoftheprecastthatwillbeinthesideofthe formduringcastingbybuilt-uprails.
K. TIF:“Topinform”indicatesthetopexposedsurfaceduringcasting.
1.4 ADMINISTRATIVE REQUIREMENTS
A. Coordination
1. CoordinatetheWorkofframingcomponentsnotpre-tensionedbutassociatedwiththeWorkofthissection.
2. Coordinatecutting,drillingorcoringinprecastmemberswiththemanufacturer. 3. Coordinateallprecastopeningorpenetrationgreaterthan10inchesinany
dimensionwiththemanufacturerpriortosubmittalofErectionDrawings.
B. Pre-installation meetings
1. Conveneminimumoneweekpriortocommencingtheonsiteworkofthissection. 2. Coordinatethesequenceofinstallationwithfoundationandsupportingelements
inplacewithprecastitemstobedelivered.
C. Site Survey:Provideasitesurveytoverifyfielddimensionsandtolerancesaminimum of2weekspriortodeliveryofprecastunitsforinstallation.
1.5 SUBMITTALS
A. Action Submittals:Provideforreviewandapproval. 1. ErectionDrawings:Indicatelayout,unitlocations,unitidentificationmarks,
connectiondetails,dimensions,openings,andrelationshiptoadjacentmaterialsandconformancewiththerequirementsoftheContractDocumentsandsealedbyprofessionalengineer.Providecoordinationinformationforitemsrequiredtobeembeddedinadjacentmaterials.
2. DesignCalculations:Submitdesigndatareportsindicatingcalculationsforloadingsandstressesoffabricatedprecastcomponents,connections,andreinforcement.CalculationsshallbepreparedbyProfessionalEngineerexperiencedinprecastconcretedesign.
3. Samples:Submitthreesamples12x12inch(304.8x304.8mm)insizeillustratingsurfacefinishtreatmentofarchitecturalfeaturedcomponent.
4. Mockup:ProvideaccesstoamockuppanelattheprecastmanufacturingplantforapprovalbytheArchitectforcolorandtexture.Theapprovedmockupshallbethecontrolstandardforcolorandtexture.
B. Informational Submittals
1. MixDesign:ProvidetheconcretedesignmixwithcertificationregardingcompliancewithrequirementsoftheContractDocuments.
2. FieldUseErectionDrawings:SubmitfielduseerectiondrawingsincorporatingcommentsfromapprovedErectionDrawings.
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3. ConstructionPlan:Submitpriortothepre-installationmeeting,aconstructionplan,includingcalculationsanddetailsforguying,stayingandshoringprecastelementstoassurestructuralstabilityduringtheerectionphase.Providefortheremoval,replacement,andrelocationofguying,bracingandshoringrequireduntilallpermanentstructuralconnectionsarecompleted.
C. Closeout Submittals
1. ProvideManufacturer’sWarrantyletter.
1.6 QUALITY ASSURANCE
A. Perform Work in accordance with requirements of PCI MNL-116,
PCI MNL-123, PCI MNL-120, PCI MNL 135.
B. Fire Rated Construction: Rating as indicated by construction type on
contract documents.
C. Source Quality Performance Testing: Provide for tests for all precast concrete
workinconformancewithPCIPlantCertificationrequirements.Usecertifiedtest equipment,andunlessotherwisespecified,conformwith: 1. ManualForQualityControlForPlantsandProductionofPrecastand
PrestressedConcreteProducts,PCIMNL-116(latestedition) 2. PCIDesignHandbook,LatestEdition. 3. ACI318fortheBuildingCodeRequirementsforReinforcedConcrete
(latestedition)
D. Mockup Control Sample Unit:Provideamockuppanelattheplant,4feetby4feet insize,forqualitycomparisonoffinishedunittoanapprovedappearancesamplefor colorandtexture.
E. The plant quality control records and inspection procedures for this project
shall be available for review, verification and in-plant inspection by an
independent testing agent or the Architect/Engineer.
1.7 QUALIFICATIONS
A. Fabricator:CompanycertifiedbythePrestressedConcreteInstitute(PCI)Plant CertificationProgramwithanin-houseengineeringdepartmentmanagedbya registeredprofessionalengineer.
B. Precast Engineer: Designprecastconcretemembersunderdirectsupervision ofProfessionalEngineerexperiencedinprecastdesignandlicensedinthestateof theproject.
C. Erector: Companywithexperienceintheerectionofprecastunitssimilartothose requiredforthisprojectandshallbeaQualifiedorCertifiedErectorunderthePCI FieldCertificationProgram.
D. Welder: QualifiedinaccordancewithAWSD1.1,AWSD1.4,andAWSD1.6
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1.8 DELIVERY, STORAGE, AND HANDLING
A. Lift and support precast concrete members during manufacturing, yarding,
transporting and erection operations only from identified support points with
suitable lifting and handling devices.
B. Lifting inserts will have a minimum safety factor of 4. Reusable lifting hardware
and rigging will have a minimum safety factor of 5.
C. Lifting or Handling Devices: Capable of supporting member in positions
anticipated during manufacture, storage, transportation, and erection.
D. Storage:
1. Protectmemberstopreventstaining,chipping,orspallingofconcrete.Store membersoffthegroundondunnagematerialsasrecommendedbyfabricator. 2. Placeallunitssothatidentificationmarksarereadable. 3. Stacksothatliftingdevicesareaccessibleandundamaged.
E. Mark each member with date of production, job number, control number, and
piece mark referenced from Erection Drawings.
1.9 WARRANTY
A. Provide Manufacturer’s Warranty for a 1-year period.
PRODUCTS
2.1 FABRICATORS
A. Fabricators:
1. TheShockeyPrecastGroup,WinchesterVirginia,Tel:(540)667-7700,www.shockeyprecast.com.
2.2 DESIGN REQUIREMENTS
A. General: Theproject,asshownonthedrawings,includingcomponentdimensionsandconnectionconfigurations,providestherequirementsforthedevelopmentofthedesigndocuments.Designshallincludeconsiderationforcustomarystressesincurredinfactoryprecasting,transporting,anderecting.Thedesign,manufacturing,transportationanderectionprocessshallbecompatiblewiththerequirementsoftheContractDocuments.
B. Design Criteria:
1. Designallledges,haunches,bearingareas,andconnectionsasrecommendedinPCIDesignHandbook.Haunches,dappedendbearingsandconnectionswithoutredundantmeansofloadtransferareconsideredcritical.
2. MinimumreinforcingforallprecastprestressedconcreteandprecastreinforcedconcreteshallbeinaccordancewithACI318.Analysisofprestressedcomponentswillincludeacheckoftheshearreinforcingrequirementsat.1L,.2L,.25Land.3L,whereListhecomponentlength.
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C. Modifications:Submitallproposedmodificationstotheprojectdesignsrepresented onthedrawingswithcompletedesigncalculationsanddrawings,preparedandsigned byalicensedprofessionalengineerforreviewandapproval.
D. Maximum Allowable Deflection:PerACI318-9.5-ControlofDeflections
E. Seismic Design: Design and detail elements and connections to resist seismic
force in accordance with code requirements and ACI 318 for the following:
1. As specified by contract documents.
F. Design members exposed to weather to allow movement of components without
damage, failure of joint seals, undue stress on fasteners or other detrimental
effects, when subject to seasonal or cyclic day/night temperature ranges.
G. Design system to accommodate construction tolerances, deflection of other
building structural members and clearances of intended openings.
H. Calculate structural properties of framing members in accordance with ACI 318.
2.3 MATERIALS
A. Concrete Materials:AsappropriatetodesignrequirementsandPCIMNL-116. 1. Cement:GrayPortland,conformingtoASTMC150TypeIorIII. 2. Cement:WhitePortland,conformingtoASTMC150TypeI
(forarchitecturalmixes). 3. FlyAshAdmixture:ASTMC618ClassCorF--25%maximum. 4. GroundGranulatedBlast-FurnaceSlag:ASTMC989Grade100or
120–40%maximum. 5. Aggregates:ASTMC33exceptasmodifiedbyPCIMNL116. 6. Air-entrainingadmixtures:ASTMC260 7. Water-reducing,Retarding,AcceleratingAdmixtures:ASTMC494 8. Pigments:Non-fading,lime-resistantpigments:ASTMC979
B. Concrete Mix Design: ACI318,Chapter5,usingstandarddeviationcalculationsinaccordancewithsection5.3.1.1or5.3.1.2. 1. Theconcretemixdesignswillconformtothefollowingrequirements: Structuralconcrete:Columns,Walls,Stairs,SpandrelBeams StrengthofConcrete–5000psiminimum Water-cementitiousmaterialsratio–maximum0.42 AirContent–5.5%+/-1.5%
Structuralconcrete:DoubleTees,Beams StrengthofConcrete–6000psiminimum Water-cementitiousmaterialsratio–maximum0.40 Aircontent–5.5%+/-1.5%
Self-ConsolidatingConcrete(SCC) StrengthofConcrete–6000psiminimum Water-cementitiousmaterialsratio–maximum0.38 Aircontent–5.5%+/-1.5%
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Architecturalconcrete: StrengthofConcrete–5000psiminimum Water-cementitiousmaterialsratio–maximum0.44 Aircontent–5.5%+/-1.5%
C. Batching concrete:
1. TheconcretebatchingplantwillbeinconformancewithASTMC94andwillbecertifiedbytheNationalReadyMixedConcreteAssociation.Volumetricbatchingofconcretewillnotbepermitted.Allmeasurementsofthevariouscomponentswillbebyweightandwillbeaccurate(withinthemostrecenttolerancelimitsofASTMC94).
2. Theuseofcalciumchlorideoradmixturescontainingchlorideionsorothersaltsisnotmorethan0.15%chlorideionsorothersaltsbyweightofadmixture.
2.4 REINFORCING AND CONNECTION MATERIALS
A. General:Provideallreinforcement,accessoryandconnectionmaterialsrequiredforacompleteinstallationasindicatedontheapproveddrawings.Pourstripreinforcementtobesuppliedandinstalledbyothersunlessspecified.ProvideGroutingasrequiredfordesignbearing.
B. Reinforcing Bars:ASTMA615,Grade60.ReinforcingusedtofabricateembeddedpartsorconnectionsbyweldingwillbeASTMA706.
C. Welded anchor studs:AWSD1.1
D. Prestressing Strand:ASTMA416,270,000psiminimumultimatestrength,uncoated,7-wire,lowrelaxation.
E. Anchor Bolts:ASTMF1554Grade36
F. Welded Wire Fabric:ASTMA185(plainsteel)orASTMA497(deformedsteel);inflatsheets;unfinished
G. Carbon Fiber Reinforcement:C-GRID®asmanufacturedbyChomarat
H. Tensioning Steel Tendons:ASTMA416/A416MGrade270Kofsufficientstrengthcommensuratewithmemberdesign.
I. Rod Anchor bars: Dayton/Superior High Strength Coil Rod, or approved equal.
J. Supports for Reinforcement for Exposed-to-View Concrete: CRSI Class 1,
plastic protected legs
2.5 ACCESSORIES
A. Connecting and Supporting Devices:
1. ASTMA36/A36Mcarbonsteel,Plates,angles,itemscastintoconcrete[or][itemsconnectedtosteelframingmembers,]insertsconformingtoPCIMNL-123;hot-dipgalvanizedinaccordancewithASTMA153/A153M.SurfacesrequiringfieldweldingshallbeZRCpainted.
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2. ASTMA666Type201LN,302or304stainlesssteel,Tee-to-Teeflange connectionsconformingtoPCIMNL-123. 3. AnchorBolts:ASTMF1554Grade36
B. Grout:Non-shrink,non-staining,minimumyieldstrengthof5,000psiat28days.
C. Bearing Pads:
1. StandardBearingPad:Rubberpadcomposedofhomogeneousblendofozone-resistantrubberelastomerandhighstrengthrandomsyntheticfibercords;Surfacehardnessof75ShoreAdurometer+/-5percent;Compression,8000psi;MASTICORDasmanufacturedbyJVIInc.orapprovedequal.
2. LaminatedFabric-rubberPads:Preformed,unusedsyntheticfibersandnewunvulcanizedrubber.Surfacehardnessof80ShoreAdurometer+/-10%.(Capralonorapprovedequal).
3. ExpansionBearingPads:Assembliesconsistingofloweranduppercomponents.Dynalonorapprovedequal.
a. Theuppercomponent:Anassemblyofasheetofstainless(14gageminimum)withaminimum2Bmillfinish.Sizedlargerthanthelowerelementbyaminimumof1/2inchineachdirection.
b. Thelowerelement:AnassemblyofaStandardBearingpad,withastainlesssteelsupportplateandabondedcontactlayerofPTFE(Teflon).
D. Shims:Steel,ASTMA36;orengineeredmultipolymerplasticmaterial,compressive strengthof8000psi;Korolath,oranapprovedequal.
E. Mechanical Splice for Future Expansion Column and Wall Reinforcing
Anchorage: Erico Lenton or NMB Splice Sleeve.
F. Double Tee Flange-to-Flange Shear Connectors:JVIVectorConnector,or approvedequal,manufacturedfromASTMA666Type201LNor304Lstainless steel,or,wherestainlesssteelisnotrequired,ASTMA36steelwithJ-Finish corrosionprotection.
G. Bolts, Nuts and Washers:ASTMA307High-strengthsteeltyperecommendedfor structuralsteeljoints;Corrosionresistantchromium-nickeltype.
H. Prime Paint: (ZRC) Zinc rich alkyd type coating.
2.6 FABRICATION
A. Fabrication procedure to conform to PCI MNL-116 and ACI 318.
B. Maintain plant records and quality control program during production of
precast members. Make records available upon request.
C. Ensure reinforcing steel, anchors, inserts, plates, angles, and other cast-in items
are embedded and located as indicated on erection drawings. Clean surfaces of
all embedded items of rust, scale, grease, and foreign matter.
D. Hardware supplied by other trades shall be furnished to the fabricator
fully assembled and tagged for location a minimum of 30 days prior to
scheduled production.
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E. Fabricate required openings with dimension larger than 10 inches (250 mm)
in diameter or larger for rectangular openings as shown and approved on erection
drawings. Provide openings in Tee stems for running electrical conduit as
coordinated with approved shop drawings; and embed accessories provided by
other Sections, at indicated locations.
F. Tension reinforcement tendons as required to achieve design load criteria.
G. Ends at Stressing Tendons:Coattheexposedendsofprestressingstrandsinallprestressedmemberswithabitumasticcoating;SonnebornHydrocide700orapprovedequal.Recessexteriorexposedtoviewendsoftendonsandpatchtomatchsurroundingsurface.
H. Weld steel fabrications in accordance with AWS D1.1. Weld reinforcing steel in
accordance with AWS D1.4. Welding processes shall not reduce the cross-
sectional area of the concrete reinforcement. Do not tack weld reinforcing. Paint
all field welds with ZRC.
I. Mark each piece of precast concrete for identification and record the date of
casting. Marks will be placed so the final appearance of the product is
not impaired.
J. Provide free access by the Architect/Engineer to all parts of the
manufacturing facility.
K. Minor patching in plant is acceptable, providing structural adequacy and
appearance of units is not impaired.
2.7 FINISHES
A. Finish exposed-to-view architectural finish surfaces of precast concrete members
to be uniform in color and appearance.
B. Cure members under similar conditions to develop required concrete quality,
and minimize appearance blemishes including non-uniformity, staining, or
surface cracking.
C. Patching where required, shall be accomplished by skilled craftsmen in such a
manner that the structural adequacy is maintained and the appearance and
durability are not impaired.
D. Provide finishes as indicated on the finishes schedule listed below.
Double Tees
1. TeeareasofCIPconcretetopping:Topsurfaceshallbetransverserakedto0.25”depthminimumtoinsurebondoftopping
2. TeeareaswithoutCIPconcretetopping:Topsurfaceshallreceiveroughhorizontalbroomorswirlbroomfinishthatshallnotexceedadepthof0.25”
3. SIF,BIFandedges:Standardformfinish 4. Depressorholes:Shallbefilledwithnon-shrink,non-staininggrouttomatch
surroundingsurfaces
76 PARKING STRUCTURE SPECIFICATIONS TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
Inverted T-Beams
1. TopsurfacestoreceiveCIPtopping:Topsurfaceshallbetransverserakedto0.25”depthminimumtoinsurebondoftopping
2. TopsurfacesnotreceivingCIPtopping:Topsurfaceshallreceiveroughbroomfinishthatshallnotexceedadepthof0.25”andthatshallbeperpendiculartothelengthofthebeam
3. SIF,BIFandedges:Standardformfinish
Columns
1. Fornon-architecturallyfinishedcolumns:SIFandBIFshallbestandardformfinish.TIFfinishshallbesteeltrowel
2. Forarchitecturallyfinishedcolumns:SIFandBIFsurfacesshallreceivefinishasprescribedbyapprovedarchitecturalsample.TIFfinishshallbesteeltrowel
Spandrels
1. TIFsurface:Shallreceivealightbroomfinishthatshallnotexceedadepthof0.125”andthatshallrunperpendiculartothelengthofthespandrel
2. SIFandBIFsurfaces:Standardformfinish 3. Forspandrelsthatrequirearchitecturalfinish:SIFandBIFwillreceivefinishas
prescribedbyapprovedarchitecturalsample
Walls
1. TIFsurface:Shallreceivealightbroomfinishnottoexceedadepthof0.125”orasteeltrowelfinish
2. SIFandBIFsurfaces:Standardformfinish 3. Forwallsthatrequirearchitecturalfinish:SIF(whererequired)andBIFwill
receivefinishasprescribedbyapprovedarchitecturalsample
Stairs
1. Topsurfaceinfinalconstruction:Roughbroomfinishnottoexceedadepthof0.25”orsandblastfinishtoprovidenon-slipsurface
2. SIFandBIFsurfaces:Standardformfinish
Flat Slabs
1. FlatslabareasofCIPconcretetopping:Topsurfaceshallbetransverserakedto0.25”depthminimumtoinsurebondoftopping
2. FlatslabareaswithoutCIPconcretetopping:Topsurfaceshallreceiveroughbroomfinishthatshallnotexceedadepthof0.25”
3. SIFandBIFsurfaces:Standardformfinish
2.8 FABRICATION TOLERANCES
A. Conform to PCI MNL-135
1. Exception:Doubleteelengths+1/4inches/-3/4inches
2.9 SOURCE QUALITY CONTROL AND TESTS
A. Test and analyze concrete in accordance with PCI MNL-116.
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EXECUTION
3.1 EXAMINATION
A. A minimum of 2 weeks prior to scheduled delivery of precast materials, verify
supporting work and site conditions are ready to receive work and field
measurements are as indicated on field use erection drawings.
B. General Contractor shall provide to fabricator verification that supporting
structure has met or exceeded the design requirements of the precast system
design as required by PCI guidelines and Contract Documents. Support
requirements shall include but not be limited to:
1. FieldPlacedBearingWallsorFootings:Providetruelevelbearingsurfaceswithelevationsof+/-1/2inchunlessshownotherwiseontheDrawings.
2. Accurateplacementandalignmentofanchorbolts,plates,ordowelsinCIPcolumnfootings,beams,wallfootings,andotherfieldplacedsupportingelements.
3. CIPConcretesupportingstructurehasmetdesignstrengthrequirementsasspecified.
3.2 PREPARATION
A. Preparesupportequipmentforerectionprocedure.
3.3 ERECTION
A. Install and secure precast units as shown on the Contract Documents and as
indicated by the field erection drawings in conformance with PCI – MNL 127.
B. Erect members without damage to structural capacity, shape, or finish. Replace or
repair damaged members.
C. Align and maintain uniform horizontal and vertical joints, as erection progresses.
D. Maintain temporary bracing in place until final support is provided.
E. Provide temporary lateral support to prevent bowing, twisting, or warping
of members.
F. Adjust differential camber between precast members to tolerance before
final attachment.
G. Secure units in place. Perform welding in accordance with AWS D1.1, and AWS
D1.6 for stainless.
3.4 ERECTION TOLERANCES
A. Erect members level and plumb within allowable tolerances.
B. Conform to PCI MNL-135 and PCI MNL 127 – Tolerances for Precast and
Prestressed Concrete Construction.
C. When members cannot be adjusted to conform to design or tolerance criteria,
consult with Architect/Engineer. Execute modifications as directed by
Architect/Engineer.
78 PARKING STRUCTURE SPECIFICATIONS TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
3.5 FIELD QUALITY CONTROL
A. Welding: Inspect welds in accordance with AWS D1.1, AWS D1.4, and AWS
D1.6 as appropriate.
3.6 PROTECTION OF INSTALLED CONSTRUCTION
A. Protect members from damage caused by field welding or erection operations.
B. Use non-combustible shields during welding operations to protect
adjacent Work.
3.7 CLEANING
A. Clean weld marks, dirt, or blemishes from surface of exposed members.
B. Remove all debris and surplus materials associated with this scope of work from
the premises.
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80 PARKING STRUCTURE SPECIFICATIONS TheShockeyPrecaSTGrouP,WincheSTer,Va•WWW.ShockeyPrecaST.coM
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GLOSSARYA
Abrasivenosing-anon-skidmetalunitwhichiscastintothenoseofaprecaststairpanel.
Addendum-asupplementtospecificationsorcontractdrawingsissuedpriortotheexecutionoftheconstructioncontract.
Admixture-amaterialotherthanwater,aggregates,andcementusedasaningredientofconcreteorgrouttoimpartspecialcharacteristics.
Admixture,airentraining–amaterialaddedtotheconcreteforthepurposeofentrainingminutebubblesofairintheconcreteduringmixingandthusimprovingthedurabilityofconcreteexposedtocyclicalfreezingandthawinginthepresenceofmoisture.
Aframe–anA-Shapedframeusedtosupportpanelsonflatbedtrucksduringshipping.
Aggregate–naturaloccurring,processedormanufacturedinorganicparticleswhicharemixedwithPortlandcementandwatertoproduceconcrete;normallycomprises60to80percentofthetotalvolumeofconcrete.
Aircraftcable–multi-strandsteelcable,inloopform,castinprecastpanelsforhandlingpurposes;cableismoreflexiblethanprestressingstrand.
Airentrainment–anincreaseintheamountofairinaconcretemixthroughtheuseofanair-entrainingadmixture(seeadmixture,airentraining);airentrainedconcretedisplaysincreasedworkabilityandcohesiveness.
Airpocket–pits(entrappedairorwaterbubbles)intheformfacesofapanelcausedbyimproperconsolidationorinadequatedraft.
Alignmentface–faceofawallpanelwhichistobesetinalignmentwiththefaceofadjacentpanels.
Anchor–(1)headedstuds,deformedstuds,straps,rebar,etc.weldedtosteelangelsorplatesandembeddedinconcreteforuseaspartofaconnection(2)anyitemcastintoorpre-affixedtothestructureforthepurposeofreceivingaconnection
Approval–acceptanceofthePrecaster’sdrawingsbytheArchitect,EngineerofRecord,andGeneralContractorindicatingthatallbuildingconditionsanddimensionsshownarecorrectandfinal.
Architecturalprecastconcrete–anyprecastconcreteunitofspecialoroccasionallystandardshapethatthroughapplicationorfinish,shape,color,ortexturecontributestothearchitecturalformandfinishedeffectofthestructure;unitsmaybestructuralordecorative,andmaybeconventionallyreinforcedorprestressed.
Assembly–asetofpartsarrangedintooneunit.
B
Backupmaterial–materialusedtolimitthedepthofthesealantinpaneljoints.
Backupmix–theconcretecastintothemoldasafillerbehindathinlayerofthemoreexpensivefacemix
Bagtie–thingagewireties(generallyNo.
16,15,or14gage)usedtofastenreinforcing
barstogetheratintersections.
Barchair–anon-corrosive,rigiddeviceusedtosupportand/orholdreinforcingbarsatagivendistancefromtheformfacebeforeandduringconcreting.
Baseplate–asteelplateanchoredtothebottomofaprecastunitforthepurposeoffastingittothefoundation.
Batch–theamountofconcreteproducedinonemixingoperation.
Beampocket–openinginaverticalmemberinwhichabeamistorest.
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Bearingarea-thesurfaceinsquareincheswhichcomesintocontactwithaverticalloadtransferringmember.
Bearingpad–apad,usuallyneoprene,
whichisplacedbetweenamemberanditssupport.
Bearingplate–asteel-orTeflon-coated
plateplacedbetweenamemberanditssupport.
Billofmaterials–materiallistforindividualproject
Bleedhole–aholdinaplateoranglewhichisprovidedsolelytoreleaseentrappedairorwaterduringconcreteplacingoperation.
Bleeding–aformofsegregationinwhichsomeofthewaterinamixrisestothesurfaceoffreshlyplacedconcrete;alsoknowaswatergain.
Blocking–theshimsrequiredtoleveland/orplumbaunitinitsproperposition.
Blockout–toformahole,orreducetheheightorwidthofapanelbyaffixingmaterialtotheform(spacewithinaforminwhichconcreteisnottobeplaced).
Bondbreaker–asubstanceplacedonamaterialtopercentitfrombondingtotheconcrete,orbetweenafacematerialsuchasnaturalstoneandconcretebackup.
Bowing–thedeflectionofaverticalpanelinasingleplane.
Bulkhead–averticalpartitionintheformblockingfreshconcretefromasectionoftheform;dividesacontinuouscastingbedintogivenunitlengths.
Bundling–placingseveralparallelelementsofreinforcementincontractwitheachother.
C
Camber–(1)theupwarddeflectionwhichoccursinprestressedconcreteelementsdue
tothenetbendingresultingfromstressingforcesandself-weight.Itspecificallydoesnotincludedimensionalinaccuraciesduetoerrorsinmanufacture,improperbearings,orotherdeficienciesinconstruction;(2)abuilt-inupwardcurvatureinsomeformsforprecastconcrete,otherthanprestressed,toavoiddeflectionunderloadtobelowadefinedlineoffinishedproduct.
Cast–toplaceconcrete(inplasticstate)intoaform.
Cast-in–catintegrallywithaconcreteunit;notstabbedinaftercasting.
Cast-in-place–concretewhichisplacedinthefield.
Caststone–precastconcretewhosefinishresemblesthatofcutorpolishedstone.
Caulking–anelastomericsealantusedtofillpaneljointsthussealingabuildingfromtheelements.
Chamfer–abeveledcorneroredgewhichisformedinconcreteworkbyplacingathree-corneredpieceofwood(cantstriporskewback)intheformcorner.
Chamferstrip–triangularorcuredinsertplacedinsidecornerofformtoproduceroundedorbeveledcorner;alsocalledfillet,cantstrip,skewback.
Clearance–thedistancebetweentwosurfaced.
Clearspan–thedistancebetweentheinsideedgesofthebearingsurfacesoftwosupportingmembers.
ColdJoint–ajointnecessitatedbyseveralcastingstagesbutdesignedandexecutedtoallowtheseparatecomponentstoappearandperformasonehomogeneousunit;termonlyapplieswhenthefirstcastingisallowedtohardenpriortoplacingthesecond.
Column–anelementusedprimarilytosupportaxialcompressiveloadsandwitha
heightatleastthreetimesitssmallestlateraldimension.
Columncover–aprecastpanelwhichcoversoneormoresidesofacolumnwhichwouldotherwisebeexposed.
Compositeconstruction–atypeofconstructionwhereinthefloorslabisfastenedtothebeamsinsuchamannerthattheyacttogetherasamoreefficientmemberincarryingliveloads.
Concrete–amixtureofportlandcement,fineaggregate,coarseaggregate,andwater.
Concrete,structurallightweight–concretethathasa28-daycompressivestrengthinexcessof2,500PSIandanair-dryunitweightoflessthan115PCF,;alightweightconcretewithoutnaturalsandistermedall-lightweightconcreteandlightweightconcreteinwhichallfineaggregateconsistsofnormalweightsandistermedsand-lightweightconcrete.
Concretecover–thecleardistancefromthefaceoftheconcretetothereinforcingsteel.
Consolidation–theuseofhandtools,vibrators,orfinishingmachinesduringthecastingprocesstoeliminatevoids,otherthanentrainedair,andtoprovideadenseconcrete,goodbondwithreinforcement,andasmoothsurface.
Coping–apanelwhichformsthetopofawallandsealsitformtheelements.
Corbel–steelorreinforcedconcretebracketwhichprotrudesfromacolumnorwallpaneltoprovidesupportforanothermemberortakesupportfromanadjacentpartofstructure.
Cornice–panelwhichfitsunderaceilingorprojectingroof.
Curtainwall–precastwallpanelswhichwheninplacemayformwindowframesandinterior/exteriorwallconstruction,butsupportnoloadsfrombuilding.
D
Deflection–thedistanceastructuralmembermovesfromitsnormalpositionwhensubjectedtoaload.
Draft–theslopeofconcretesurfaceinrelationtothedirectioninwhichtheprecastelementiswithdrawnfromthemold;itisprovidedtofacilitatestrippingwithaminimumofmoldbreakdown.
Drip–aprojectingfinorgrooveattheouteredgeofasill,projectinghorizontalwallelementorsoffit,designedtointerrupttheflowofrainwaterdownwardoverthewallorinwardacrossthesoffit;dripsarenormallyusedonlyonunitshavingsmoothorlightlyexposedfinish.
E
Elongation–inprestressedwork,thedifferencebetweenastrand’sinitiallengthanditslengthafterstressing.
Engineerofrecord-engineerwhocreatesoriginalbuildingdesignandisresponsibleforthedesign.
Erection–theplacingofprecastunitsintotheirrespectivepositionsinthestructure.
Expansionboltoranchor–anexpandabledevicemadeofmetalinsertedintoadrilledholeinhardenedconcretethatgripsconcretebywedgingactionwhenthenutorheadisrotated.
F
Fabrication–actualworkonreinforcingbarsorhardwaresuchascutting,bending,andassembly.
Face–thesurfaceofapanel.
Facemix–theconcreteattheexposedfaceofaconcreteunit;usedforspecificappearancereasons.
Falsejoint–scoringonthefaceofaprecastunit;usedforaestheticorweatheringpurposesandnormallymadetostimulateanactualjoint.
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Fascia–theoutsidehorizontalpanelontheedgeofarooforoverhang.
Fenestration–thedesignandplacingofwindowsinabuilding.
Finish-treatmentortexturegiventoconcretesurfaces.
Form–atemporaryreceptaclewhichreceivesconcreteanddictatesaunit’sshape.Itcanbemadeofwoodorsteel,butrequiresnotpatternorpositive.
Formliner–moldedsheetwhichwhenaffixedtoaformgivesthepanelaspecialfinishtreatment;linersaremadeofrubber,plastic,wood,etc.
Formreleaseagent–asubstanceappliedtotheformsforthepurposeofpreventingbondbetweentheformandtheconcretecastinit.
G
Galvanize-tocoatwithrustresistantzincbyspraying,dipping,orelectrolyticdisposition.
Gradation–thesizingofgranularmaterials.Forconcretematerials,usuallyexpressedintermsofcumulativepercentageslargerorsmallerthaneachofaseriesofsieveopeningsorthepercentagesbetweencertainrangesofsieveopenings.
Grout–amortartypemixturewhichishandpackedorappliedunderpressureinsuchaconsistencyastoensurecompletefillingofallvoids.Theusualproportionsofagroutmixareone(1)partofcementtothree(3)partsofwell-gradedsandbyweightwithwatercontentadjustedsothatamassofgroutsqueezedinthehandremainsitsshape.
H
Hardware–acollectivetermappliedtoitemsusedinconnectingprecastunitsorattachingoraccommodatingadjacentmaterialsorequipment.Hardwareisnormallydividedintothreecategories:
Contractor’sHardware–itemstobeplacedonorinthestructureinordertoreceivetheprecastconcreteunits:e.g.,anchorbolts,angels,orplateswithsuitableanchors.
PlantHardware–itemstobeembeddedintheconcreteunitsthemselves,eitherforconnectionsandprecasterector’swork,orforothertrades,suchasmechanical,plumbing,glazing,miscellaneousiron,masonry,orroofingtrades.
ErectionHardware–allloosehardwarenecessaryfortheinstallationoftheprecastconcreteunits.
Honeycomb–acoarsestonyconcretesurfacewithvoidslackinginfines;someprobablecausesarecongestedreinforcement,narrowsection,insufficientfines,lossofmortar,andinadequateconsolidation.
I
Insert–aconnectingorhandlingdevicecastintoprecastunits.Insertsaremachineorcoil-threadedtoreceiveaboltorslottedtoreceiveabolthead.
J
Joint–Thespacebetweentwoadjacenterectedpanels.
K
Key–acontinuousorsemi-continuousslotinconcretetoreceivegrout,levelingblocks,ordowels.
L
Liftingdevice–anassemblyusedinhandlingorerectionofprecastpanels.
Liftpoint–predeterminedpointsfromwhichapanelistobelifted.
Loadbearing–supportingthedeadandliveloadofothermembers.
Load-bearingprecastunits–precastunitswhichformanintegralpartofthebuildingstructureandwhichareessentialtoitsstability.
M
MarkNumber–theindividualidentifyingmarkassignedtoeachprecastunitpredeterminingitspositioninthebuilding.
MasterMold–amoldwhichallowsamaximumnumberofcastsperproject;unitscastinsuchmoldsneednottobeidentical,providedthechangesintheunitscanbeaccomplishedsimplyaspre-engineeredmoldmodifications.
Matrix–theportionoftheconcretemixcontainingonlythecementandfineaggregates(sand).
Maximumsizeaggregate–aggregatewhoselargestparticlesizeispresentinsufficientquantitytoaffectthephysicalpropertiesonconcrete;generallydesignedbythesievesizeonwhichthemaximumamountpermittedtoberetainedis5or10percentbyweight.
Mitre–theedgeofapanelthathasbeenbeveledtoanangleotherthan90degrees.
Mockup–asectionofawallorotherassemblybuiltfullsize,ortoscale,forpurposesoftestingperformance,studyingconstructiondetails,orjudgingappearance.
Module–arepeatingorreoccurringdimensionordetail.
Mold–thecavityorsurfaceagainstwhichfreshconcreteiscasttogiveitadesiredshape;sometimesusedinterchangeablywithformbutmadeoffiberglassorconcrete;apatternorpositiveisbuiltfirstandthemoldisoverlayed.
Mortar–amixtureofcement,sand,andwater;whenusedinmasonryconstruction,themixturemaycontainmasonrycement,orportlandcementwithlimeorotheradmixtureswhichmayproducegreaterdegreesofplasticityand/ordurability.
Mullion–averticalprecastunitappearingbetweenwindowsand/ordoors.
Muntin–horizontalprecastappearingbetweenwindowsand/ordoors.
N
Nailer–abeveledwoodenstripcastintoaprecastpanelforthepurposeofnailingflashingorroofingtoit.Theuseofsuchmaterialinconcreteisnotrecommended.
Neoprene–asyntheticrubberbearingpad.
Normalweightconcrete–concreteforwhichdensityisnotacontrollingattributeandusuallyhavingunitweightsintherangeof135to160lbs.percubicfoot.
Nosing–aprojectionsuchasthatofthetreadofastairovertheriser.
O
Overhang–theprojectingareaofarooforupperstorybeyondthewallofthelowerpart.
P
Panel–anindividualprecastunit
Parapet–thatpartofthewallthatextendsabletheroofline.
Patch–torepairasuperficiallydamagedpanelbyfillingthedamagedareawithconcreteofmatchingcolorandtexture.
Pier–ashortcolumnusedasafoundationmemberinbuildingconstruction.
Pilaster–columnpartiallyorcompletelyembeddedinawall,oraportionofawallenlargedtoserveasacolumn.
Plate–asheetofmetalhavingathicknessof1/8inchorgreater.
Platewasher–aspecialwasherprefabricatedfromsteelplate.
Pouredinplace–(seecast-in-place)
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Precastconcrete–aplainreinforcedorprestressedconcreteelementcastinotherthanitsfinalpositioninthestructure;precastconcretecanbearchitecturalorstructural.
Precastengineer–thestructuralengineerauthorizedbythemanufacturertoensuretheadequacyofthestructuralaspectsofthedrawings,manufacture,andinstallationforwhichthemanufacturerisresponsible.
Preliminary-notcompletelyfinalizedandreviewed.
Prestressedconcrete-concreteinwhichtherehavebeenintroducedinternalstressesofsuchmagnitudeanddistributionthatthestressesresultingfromloadsarecounteractedtoadesireddegree.
Prestressingbed-theplatformandabutmentsneededtosupporttheformsandmaintainthetendonsinastressedconditionduringplacingandcuringoftheconcrete.
Pretensioning–amethodofprestressingconcretewherebythetendonsareelongated,anchoredwhiletheconcreteinthememberiscast,andreleasedwhentheconcreteisstrongenoughtoreceivethestressesfromthetendonthroughbond.
Q
Quirkmitre–acornerformedbytwochamferedpanels.
R
Rebar–abbreviatedtermforreinforcingbar.
Reinforcedconcrete–concretecontainingreinforcement,includingprestressingsteel,anddesignedontheassumptionthatthetwomaterialsacttogetherinresistingforces.
Reinforcement–mesh,strand,orpost-tensioningcablesembeddedinconcreteandlocatedinsuchamannerthatthemetalandtheconcreteacttogetherinresistingloads.
Release–(1)thetimeatwhichtheprestressedstrandsareseveredpriorto
removingtheprestressedunitsfromtheforms;(2)submittalofdrawings;(3)strippingofprecastpanel
Releaseagent–(seeformreleaseagent)
Retarder–anadmixturewhichdelaysthesettingofcementpasteandthereforeofconcrete
Retarder,surface–amaterialusedtoretardorpreventthehardeningofthecementpasteonaconcretesurfacewithinatimeperiodandtoadepthtofacilitateremovalofthispasteaftertheconcreteelementisotherwisecured(amethodofproducingexposedaggregatefinish).
Return–aprojectionoflikecross-sectionwhichis90degreestoorsplayedfrommainfaceorplaneofview.
Reveal–(1)grooveinapanelfacegenerallyusedtocreateadesiredarchitecturaleffect;(2)theprojectionofthecoarseaggregatefromthematrixafterexposure.
Rib–(1)continuousverticalprojectiononawallpanelprojectingaminimumof6inchesfromthepanelface;(2)localthickeningprovidingstiffnessinconcretepanels.
Rustication–agrooveinapanelfaceforarchitecturalappearance;alsoreveal.
Rusticationstrip–astripofwoodorothermaterialattachedtoaformsurfacetoproduceagrooveorrusticationintheconcrete.
S
Sand-thatportionofanaggregatepassingtheNo.4(4.76mm)sieveandpredominantlyretainedontheNo.200(74micron)sieve.
Sandblast–asystemaabradingasurfacesuchasconcretebyastreamofsand,orotherabrasive,ejectedfromanozzleathighspeed,bywaterand/orcompressedair.
Sandwichwallpanel–panelconsistingoftwolayers(wythes)ofconcretefullyorpartlyseparatedbyalayerofinsulation;inemployingthisdetail,metalshearconnectorsareusuallyrequiredtotiethetwolayersofconcretetogether.
Sealants–agroupofmaterialsusedtosealjointsbetweenprecastconcreteunitsandbetweensuchunitsandadjacentmaterials.
Sealersorprotectivecoatings–materialsusedtocoastprecastconcreteunitsforthepurposeofimprovingresistancetowaterpenetrationorforimprovingweatheringqualities.
Section–cutawayviewthroughageneralplanorelevationviewtoexplaindetails.
Segregation–thetendencyforthecoarseparticlestoseparatefromthefinerparticlesinhandling;inconcrete,thecoarseaggregateanddriermaterialremainsbehindandthemortarandwettermaterialflowsahead;thisalsooccursinaverticaldirectionwhenwetconcreteisoverbibratedordroppedverticallyintotheforms,themortarandwettermaterialrisingtothetop;inaggregate,thecoarseparticlesrolltotheoutsideedgesofthestockpile.
Selfstressingforms–equipmentwhichinadditiontoservingasformsforconcretealsoaccommodatesthepre-tensionedstrands(orwires)andsustainsthetotalprestressingforcebysuitableendbulkheadsandsufficientcross-sectionalstrength.
Set-up–theprocessofpreparingmoldsorformsforcasting,includinglocatingmaterials(reinforcementandhardware)priortotheactualplacingofconcrete.
Slab–precastorprestressedfloororroofmembers.
Spandrel¬–thatpartofawallbetweentheheadofawindowandthesillofthewindowaboveit.(Anupturnedspandrelcontinuesabovetherooforfloorline.)
Spandrelbeam–beaminabuildingframe
whichextendsbetweenexteriorcolumnsatafloorlevel.
Specifications–thetypeorprinteddirectionsissuedbyarchitectstoestablishgeneralconditions.Standardsanddetailedinstructionswhichareusedwiththecontractdrawings;contractedterm,specs.
Stoneanchor–ananchorcommonlyusedtofastencutstoneunits;suchanchorsareseldomsuitableforuseinprecastconcreteattachment.
Stress–intensityofforceperunitarea.
Stripping–theprocessofremovingaprecastconcreteelementfromtheforminwhichitwascast.
Strongback–asteelorwoodenplatewhichisattachedtoapanelforthepurposeofaddingstiffnessduringhandling,shipping,and/orerection.
Structural–aunitwhichcarriesliveloadoranotherunit’sweight.
Submitted–presentedtothearchitect/engineerforreview.
Systemsbuilding–essentiallytheorderlycombinationof“parts”intoan“entity”suchassub-systemsortheentirebuilding;systemsbuildingmakesfulluseofindustrializedproduction,transportation,andassembly.
T
Temperaturereinforcement–reinforcementdistributedthroughouttheconcretetominimizecracksduetotemperaturechangesandconcreteshrinkage.
Tie–aclosedloopofsmallsizereinforcingbarsthatencirclelongitudinalbarsincolumnsandbeams.(seestirrup)
Tolerance–specifiedpermissiblevariationfromstatedrequirementssuchasdimensions,strength,andair-entrainment.
Topping–concretecastonerected
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prestressedunitstoachievealevelfloorortoaidtheunitsinuniformlycarryingloads.
V
Vibration-energeticagitationofconcretetoassistinitsconsolidation,producedbymechanicaloscillatingdevicesatmoderatelyhighfrequencies;externalvibrationemploysadeviceattachedtotheformsandisparticularlyapplicabletothemanufactureofprecastitems;internalvibrationemploysanelementwhichcanbeinsertedintotheconcrete,andismoregenerallyusedforcast-in-placeconstruction.
W
Wallpanel–acomponentofaprefabricatedwallwhichderivesitsstrengthanddimensionalstabilityfromaprecastconcreteelement;thecomponentincludesanynonconcreteitemsincorporatedintheelementatthetimeofmanufacture.
Warping–thebowingofaprecastunitintwoplanes.
Weephole–aholeprovidedfordrainagethroughprecastpaneljoints
Weld–tojoinmetalsbyapplyingheatwithafillermetalwhichhasahighmeltingpoint.
Weldedwirefabric–areinforcingmaterialcomposedofcolddrawnsteelwiresfabricatedintoasheetconsistingoflongitudinalandtransversewiresarrangedatrightanglesandweldedtogetheratallpointsofintersection.
Weldplate–aplatewithattachedanchorscastintoconcreteforthepurposeofmakingaweldedconnection.
Workability–theeasewithwhichagivensetofmaterialscanbemixedintoconcreteandsubsequentlyhandled,transported,placed,andfinishedwithaminimumlossofhomogeneity.
T h e S h o c k e y P r e c a s t G r o u p
219 Stine Lane
Winchester, VA 22603
540.667.7700
www.shockeyprecast.com
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