延性材料开裂机理及抗断设计

38320066西安建筑科技大学学报()JXianUniv.ofArch.&Tech.(NaturalScienceEdition)Vol.38No.3Jun.2006王万祯1,顾强2(1.,730050;2.,215011):,,,:F=Y1-.,,.,.:;;;;;:TU391:A:10067930(2006)03036807*1994(Northridge)1995,,,.,,.,,,,[1].,,,,.,[2].[3],.1深槽刻痕杆应力三轴空间分析1.1,,.,.,.:[4].,.,:1[]=F/k(1),,F.,,F.,[4].[3][5],,:seq=12[(1-2)2+(2-3)2+(3-1)2][]=Y/k(2)*:20051120:(3ZS051A25044);(SB04200408;0416B05):(1974),,,,.,,[2]!.∀1.2,,,.,:.,.,,.,,;!∀,.H/seq,,!∀[6].,.,.,,.,,,.,,,,.,,.::KiKic(i=#,∃,%);:GiGic(i=#,∃,%);J:JIJIC;(CTOD):CTOD[7].a,,[8],,.,,.,,,:!∀.FY,Y,,F.1.31,,.D2D1L2L1,,,:2&3&1().图1深槽刻痕杆拉断试验示意图Fig.1Fracturetestofnotchedbar图2深槽刻痕杆的有限元网格Fig.2FEmeshesofnotchedbar,ANSYSSolid951.D1=10mm,D2=200mm,L1=20mm,L2=200mm.,3693:(,Y,),2.[9],:E=69000N/mm2,=0.3,!Y=0.00507,Y=350N/mm2,!u=0.105,u=484N/mm2.Mises,,,.Y=0Y=2mmY=5mm()3.:,,.0.3,,x,N&z,N&0.3y,N=y,N.,,.图3刻痕截面的横向约束Fig.3Constraintofcrosssectioninnotchedbar:,,!∀,,,,1F[7].210mm,(1)(2):y,N=F;seq,N-r(3)x,N&z,N&y,N(2):seq,N=(1-)y,N(4)(3)(4):F=Y1-(5),[9].2开孔铝合金矩形板的断裂分析2.1[9]418(Al2024T351),50mm,1.图4试件的外形Fig.4Shapesofspecimen,200kN0.2mm/s.50mm.,,.1(:mm)Tab.1Geometrydimensionsofspecimens(units:mm)Specimens123456789101112131415161718Thickness23452345235234581012Diameter1010101020202020303030404040404040402.21.3,.8(:400mm),.,,50mm.,,,,5.370()38图5有限元模型的网格Fig.5MeshesofFEmodel1∋186∋9,,.:,SP11SP17SP18,0.3mm,12%.,,,..,SP16SP18-7.6%-7.1%,.,,.SY.图6试件1∋4的模拟力位移曲线Fig.6Simulatedforcedisplacementcurvesofspecimen1∋4图7试件5∋8的模拟力位移曲线Fig.7Simulatedforcedisplacementcurvesofspecimen5∋8图8试件9∋13的模拟力位移曲线Fig.8Simulatedforcedisplacementcurvesofspecimen9∋13图9试件14∋18的模拟力位移曲线Fig.9Simulatedforcedisplacementcurvesofspecimen14∋18[9]Y=350N/mm2=0.3(5),:SF=F=Y1-=3501-0.3=500N/mm2.10∋131∋18(4Y=0Z=)SYSFSY/SF.(:0;1).3713:图10试件1∋4板边缘最大主应力分布Fig.10DistributionofmaximalnormalstressesofSP1∋4图11试件5∋8板边缘最大主应力分布Fig.11DistributionofmaximalnormalstressesofSP5∋8图12试件9∋13板边缘最大主应力分布Fig.12DistributionofmaximalnormalstressesofSP9∋13图13试件14∋18板边缘最大主应力分布Fig.13DistributionofmaximalnormalstressesofSP14∋18:,SP12∋18,SYSF.,SP1∋4,SY(20%)SF,.!∀,[9],.10∋13:,SYSF1.0,SP110%.:(5),[9],,,(5).,(5),.3设计建议与展望[10],14.14(),,,Y,,F,372()38图14延性材料断裂和屈服的设计建议Fig.14Designsuggestionsoffractureandyield.1/seq,,,.,,kFkY,.,,.(,),FY[2,11].,,(5).FY,.,(5),.,,,.,.,.,.,.References[1],.()[M].:,2003:301316.CHENShaofan,GUQiang.Steelstructure(Volume#)[M].Beijing:ChinaArchitecture&BuildingPress,2003:301316.[2].[M].:,1998:2944.CHENShaofan.PrincipleofSteelStructureDesign[M].Beijing:SciencePress,1998:2944.[3]GB500172003,[S].:,2003:6367.GB500172003,Codefordesignofsteelstructures[S].Beijing:ChinaPlanPress,2003:6367.[4],,.()[M].:,1987:5377.SUNXunfang,FANGXiaoshu,GUANLaitai.Materialmechanics(Volume∃)[M].Beijing:HighEducationPress,1987:5367.[5]JGJ9998,[S].:,1998:6690.JGJ9998,Technicalspecificationforsteelstructureoftallbuildings[S].Beijing:ChinaArchitecture&BuildingPress,1998:6690.[6]LEMAITREJA.ACourseonDemageMechanics[M].Berlin:SpringVerlag,Germany,1996:1547.[7],,.[M].:,1998:140176.KUANGZhenbang,GUHaicheng,LIZhonghua.Mechanicsbehaviorofmaterial[M].Beijing:HighEducationPress,1998:140176.[8]SCHAFERBW,OJDROVICRP,ZARGHAMESMS.TriaxialityandFractureofSteelMomentConnections[J].JournalofStructuralEngineering,2000,126(10):11311139.[9]BAOYingbin.DependenceofFractureDuctilityonThickness[J].ThinWalledStructures,2004,42:12111230.[10]GENSAMERM.StrengthofMetalunderCombinedStress[M].Cleveland:AmericanSocietyforMetals,1941:1142.[11].[M].:,2003:133152.LIUXiaomin.Microcosmicstructureandmechanicsbehaviorofengineeringmaterial[M].Hefei:UniversityofScienceandTechnologyofChinaPress,2003:133152.(编辑李斌)(下转第424页)3733:tion[J].PharmaceuticalEngineeringDesign,2002,23(4):1720.(编辑李斌)Growthhabits,characteristicsandkillingexperimentofchironomidlarvaeindrinkingwaterHUANGTinglin1,WUHaixia2,SONGLitong1(1.SchoolofEnvi.andMuni.Eng.,XianUniv.ofArch.&Tech.,Xian710055,China;2.CollegeofUrbanConstructionandSafety&EnvironmentalEngineering,NanjingUniversityofTechnology,Nanjing210009,China)Abstract:Theemergenceofchironomidlarvaeinwatertreatmentunitsisbotheringmunicipalwatersupplypracticeintheseyears.Thesealwaysfloatedintotheplantwiththeinflowofsurfacewaterandpipesintheunits.Aftercollectingthelarvaesamples,wehaveprovidedanoptimumhabitatforchironomidpopulationincubationinlab.andobservedtheirhabitsandcharacteristics.Sodiumhypochlorite(NaClO),hydrogenperoxide(H2O2),potassiumpermanganate(KMnO4),chlorinedioxide(ClO2),ozone(O3)areusedtoinactivateandkillthemidgelarvaeatdifferentdosage,pHandcontacttime.Itturnedoutthattheinactivationeffectofozoneisbetterthanothers.Under30minofcontacttimeandatadosageof1.5mg/L,ozonecouldkillthelarvaescompletely.Keywords:Chironomidlarvae;inactivation;oxidationBiography:HUANGTinglin,Professor,SupervisorofPh.D.Candidate,Xian710055,P.R.China,Tel:[phone],Email:[e-mail](上接第373页)CrackmechanismandfracturedesignofductilematerialWANGWanzhen1,GUQiang2(1.CollegeofCivilEngineering,LanzhouUniversityofTechnology,Lanzhou730050,China;2.SchoolofCivilEngineering,UniversityofScience&TechnologyofSuzhou,Suzhou215011,China)Abstract