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:20040825:(BK2001201):(19722),,,,,1343Vol.34No.320055JournalofChinaUniversityofMining&TechnologyMay2005:100021964(2005)03202742051,2(1.,221008;2.,210096):,.,,1,,..:;;;;;;:TU375:ACalculatingofExpansionJointSpacingofReinforcedConcreteFrameStructuresLIFu2min1,MENGShao2ping2(1.CollegeofArchitectureandCivilEngineering,ChinaUniversityofMining&Technology,Xuzhou,Jiangsu221008,China;2.CollegeofCivilEngineering,SoutheastUniversity,Nanjing,Jiangsu210096,China)Abstract:Thevaluesofexpansionjointspacingofreinforcedconcretestructuresaregivenbysomestandards.Buttheeffectofusingthesevaluesisnotverysafisfactory.Tofindthereasonablevaluesitisnecessarytotakeaccountoftwofactors:1)thestressescausedbytemperatureandshrinkagearelessthantheallowablestresses;2)thecompositecrackingwidthhastobewithintheallowablerange.Onthebasisoftheabove2namedanalysistheaveragetensionstresseswithincludingtheeffectofcreepandcrackingwereexaminedinthemiddlesectionsofregularsinglelayerframesimplifiedfrommultilayerframe.Bytheexaminingaformulacalculatingtheexpansionjointspacingofreinforcedconcreteframestructureswasdeduced.Intheformulatheseveralmainfactors,suchasthefreestraininducedbytemperatureandshrinkage,structurerestraining,steelratioofcrosssectionandthecharacteristiccombinationstressinreinforcements,weretakenintoconsideration.Twocalculatingexamplesindicatethattheformulaisrationalandusable.Keywords:framestructures;temperatureandshrinkage;structurerestraining;cracking;expansionjoints;allowablestress;steelratio,[123],[429].,,,©1995-2006TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.[10](),,[11].,,,,,.,.[11];,,.1,,.(),,,,,,;(),,,,,,.,,,:,,.2,.,,.,,.,,.,,,,,.,,[12],K=0.4.1,O,bh,Ab;Asb;A,E;,,D.,,;,nn,.,,[11],Qnni=1Qi=y+l2lQn,(1)1Fig.1Diagramofcalculatingthetemperatureandshrinkagestressinframestructures2,Qn$1(),$1$2()$();$2Qi,$E,Qn=Ey2y2-3yl-5l26lEA+1D.(2)2Fig.2Diagramofcalculatingtheshearstressinend2columns5723:©1995-2006TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,Re=ni=1QiA=y+l2lAQn.(3)RKRe=R.(4)K=0.4(3),(2)(4)2D(3EE-5R)y2+6Dl(EE+2.5R)y+25DWRl2-30EARl=0.(5)y,y=3EAlRD(0.6EE-R)-0.5l.(6)2Lmax=23EAlRD(0.6EE-R)-l,(7):Lmax,m;E,,kNöm2;D,,kNöm;A,,m2;l,m;E,(:,),,,,[11,13214];R(),kNöm2,,R(12);,R(12),R0.8ftk(ftk,kNöm2),.3wmax=SlSsAcWRskEslcr,(8):Rsk;Sl,1.5,[15],,70%,,$Rsh.T=0.7(Sl-1)Rsk=0.35Rsk.(9)0.35Rsk.3,3Fig.3Diagramofforcesinbend2tentionmembersectionNsh2T(Cs-0.5)h0=0.35As0RskCsh0,(10)0.5h0;Cs=0.87,Nsh2T=AcR,R=0.82QRsk.(11)R,wmax,wmaxwlim,R,(11)RR=kQRsk,(12):k=1.35wlimöwmax-10.425.(13),,,(0.8),R0.8=ftk,(14)R=0.8ftk,ftk,kNöm2.67234©1995-2006TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.4[]4,3.6m,200mm400mm,90mm,400mm400mm;C20,;3516(HRB335,603mm2,Q=0.00754),8@180(HPB235,Q=0.00310);-25,310-4.4Fig.4Theframestructureplanofahotelbuilding48.07m.8@100(HPB235,Q=0.00559),,67.24m.[]C9(),(7.2+2.4+7.2)7.2m,;3.5m,250700mm,200mm600mm,100mm,500mm700mm(700mm);C40,;3520(HRB335,942mm2,Q=0.00538),8@180(HPB235,Q=0.00279).102m,,.11.,0.4mm,..-10,510-4.27.3m,55m,,.,,..5,,,,.,;,,.,,.:[1]JosMiltondeArajo,ArmandoMiguelAwruch.Crackingsafetyevaluationongravityconcretedamsduringtheconstructionphase[J].Computers&Structures,1998,66(1):932104.[2]KimJK,LeeCS1Predictionofdifferentialdryingshrinkageinconcrete[J].CementandConcreteResearch,1998,28(7):9852994.[3]YuanZL.ofcrackingwithinearly2ageconcreteduetothermal,dryingandcreepbehavior[J].CementandConcreteResearch,2002,32(7):105321059.[4].T[J].,1994,15(6):31237.GaoLR.ThelongitudinalprestressingtendonframewithoutexpansionjointsandLinTeesystem[J].JournalofBuildingStructures,1994,15(6):31237.[5],,,.UEA[J].,1998,28(6):21223.YouBK,LiGM,WangDM,etal.ThemethodofdesignandconstructionofsuperlongR.C.structureswithoutjointsbyusingUEA[J].BuildingStructures,1998,28(6):21223.[6]FernandoH,GuillermoS,JuanAB.Oresundbri2dge,Temperatureandcrackingcontrolofthedeck7723:©1995-2006TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.slabconcreteatearlyages[J].AutomationinConstruction,2000,9(526):4372445.[7]..,2000(5):326.WangTM.Crackingcontrolofreinforcedconcreteconstruction[J].Concrete,2000(5):326.[8]..,2001,31(5):33235.LuSL.Thecrackingcontroldesignofsuperlongconcretestructuresofbasement[J].BuildingStructures,2001,31(5):21223.[9]SuleM,BreugelvanK.Theeffectofreinforcementonearly2agecrackingduetoautogenousshrinkageandthermaleffects[J].Cement&ConcreteComposites2004,26(5):5812587.[10].(GB5001022002)[S].,,2002.[11].[M].:,1997.[12].[D].:,2003.[13]AhmedL,DavidC,AbdelhafidK,etal.Anewap2proachtodetermineautogenousshrinkageofmortaratanearlyageconsideringtemperaturehistory[J].CementandConcreteResearch,2000(30):9152922.[14]PietroL,KlaasvanB,IppeiM.Effectofcuringtemperatureandtypeofcementonearly2ageshrinkageofhigh2performanceconcrete[J].CementandConcreteResearch,2001,31(12):186721872.[15].()[M].:,1998.()(273)[11],.[J].,2000,5A(3):2062210.YaoYR,ZhangYJ.Shape2basedimageretrievalusingwaveletandmoment[J].JournalofImageandGraphics,2000,5A(3):2062210.[12],,.TM[J].,2003,7(1):37241.ZhaY,NiSX,YangS.AneffectiveapproachtoautomaticallyextracturbanlandusefromTMimage[J].Journalo