聚乙烯管韧性破坏寿命预测方法研究-徐成

112231．3100272．3100273．3100203、。。。。。TH145．4TB302．3A1001－4837201201－0001－06doi10．3969/j．issn．1001－4837．2012．01．001PredictionofDuctileRuptureFailureLifeofHDPEPipeXUCheng1XUPing1SHIJian－feng2GUOWei－can231．InstituteofAppliedMechanicsZhejiangUniversityHangzhou310027China2．InstituteofProcessEquipmentZhejiangUniversityHangzhou310027China3．ZhejiangSpecialEquipmentInspectionandResearchInstituteHangzhou310020ChinaAbstractTherearethreetypicalfailuremodesofhighdensitypolyethyleneHDPEpipeunderhydro-staticpressurewhichareductilerupturecausedbycreepslowcrackgrowthanddegradation．Thedura-tiontimeofHDPEpipeunderhydrostaticpressurebeforeductilerupturefailureispredictedbasedonavisco－elasticmodel．ItisfoundthathoopstressincreasesduetoreductioninwallthicknessofHDPEpipewhileyieldingstressdecreasesowingtodecreaseofstrainrate．WhenthehoopstressapproachestheinstantyieldingstressHDPEpipequicklydeformsandthenstructuralfailurewillfollow．Therela-tionshipbetweenhydrostaticpressureandfailurelifeofHDPEpipeareobtained．Keywordspolyethylenepipeyieldstressvisco－elasticmodelductilerupturefailurelife0、、1。2011BAK06B0112。PPIISO90803logtf=A+BT+C+DTlogσθ1tf———hT———℃ABCD———σθ———MPa。。341。－15－2－350。13PE100。。。。11．1PE80D90SDR11。GB/T8804．3《3》。2。21．2WDW－1001。1/kN/%/mm/mm·min－11000．5±0．10．0010．0005～5002。1．323℃6h10－210－310－410－53×10－6/s。2CPVTVol29.No120122/mm/mm/mV·V－1/mm501D0～252．210．00122．13—。。3—。6。。7。Eyring8。PE804。σy=24．307+2．063logε·2ε·———s－1σy———ε·MPa42．2Suleiman9σ=εa+bε3ab———MPa－110－210－310－410－53×10－6/s35ab6a=a1lnε·+a2b=b1lnε·+b24a1a2b1b263。2．32．3．11SDR1110σθ=pd2h5p———MPa3291230d———mmh———mm5—ab63a1－7．77×10－5a23．79×10－4b1－2．771×10－3b22．84×10－222πd0h0=2πdihi6d0———mmh0———mmdi———immhi———imm65σi=pdi22d0h07σi———iMPadi=d01+εei8εei———iε=ln1+εe97σi=pd0exp2εi2h010310－6～10－2/s。2．3．21υ=0．1MPa/sε·1。ε1=pvε·1119σ1=pd0exp2ε12h0121234ε·1。24CPVTVol29.No12012。。1h1h。εi=εi－1+3600ε·i13σi=pd02h0exp2εi－1+3600ε·i14σ=εa+bε=εia1lnε·i+a2+b1lnε·i+b2εi153。13～15ε·i3ε·i+1。32σθ≥σy=24．307+2．063logε·16tf。33．1SDR11σθ=5p。1．7MPa7。7。。。3．2SDR114。4/MPa/MPa/h2．110．582．010．0211．99．5641．89．02361．78．510291．68．054621．57．5363668。85291230。logtf=－25．398logσθ+26．86917172－3。41Suleiman2。3PE80DN90SDR11。1．J．200724545－49．2．M．2002273－293．3ThePlasticPipeInstitute．TR－3/2010HDB/HDS/PDB/SDB/MRSPoliciesS．2010．4KrishnaswamyR．AnalysisofDuctileandBrittleFail-uresfromCreepRuptureTestingofHigh－densityPo-lyethyleneHDPEPipesJ．Polymer2005462511664－11672．5．J．1992124218－227．6．D．200518－19．7．J．1995316248－253．8．M．2008232－235．9MuhannadTSuleimanBrianJCoree．ConstitutiveModelforHighDensityPolyethyleneMaterialSys-tematicApproachJ．JournalofMaterialsinCivilEngineering2004166511－515．[e-mail]。265。EPR。1．J．201027536－43．2RCC－MS．3EJMAS．4S2008．5．UJ．201128724－28．[e-mail]。6CPVTVol29.No12012