PRC橋墩抗震性能研究現(xiàn)狀和展望

Abstract

Withtheincreasingfrequencyofnaturaldisasters,ensuringthesafetyofinfrastructurehasbecomeaworldwideconcern.Asoneofthemostimportantcomponentsofinfrastructure,bridgesmustbedesignedtowithstandearthquakesandotherexternalforces,ensuringpeople'ssafetyandthesmoothflowoftransportation.ThispaperfocusesonthecurrentresearchstatusandprospectsoftheseismicperformanceofPRCbridgepiers,analyzingtheresearchmethods,models,andinfluentialfactors.Thestudyaimstoprovidetheoreticalguidanceforthedesignandconstructionofhigh-performancePRCbridgesandtopromotethedevelopmentofseismic-resistantPRCmaterialsandtechnologies.

Keywords:PRCBridgePiers,SeismicPerformance,ResearchStatus,Prospects

Introduction

Asanessentialpartoftransportationinfrastructure,bridgesplayacrucialroleinsocialandeconomicdevelopment.However,naturaldisasterssuchasearthquakes,typhoons,andfloodshaveseverelythreatenedthedurabilityandstabilityofbridges.Inparticular,earthquakesgeneratestronggroundmotionthatcanresultindamageandevencollapseofbridges,causinglossoflife,propertydamage,anddisruptionstotransportationnetworks.Therefore,theseismicperformanceofbridgeshasbeenthefocusofextensiveresearchworldwide.Inthedesignprocessofbridges,theselectionofseismic-resistantmaterialsiscrucial.

InChina,PRC(PrestressedReinforcedConcrete)technologyhasbeenappliedextensivelyintheconstructionofbridgesduetoitsremarkableadvantages,suchashighstrength,gooddurability,andanti-fatigueperformance.However,researchontheseismicperformanceofPRCbridgepiersisstillintheinitialstage,andtheunderstandingofitsseismicbehaviorisincomplete.Therefore,itisnecessarytoreviewthecurrentresearchstatus,tosummarizetheresearchmethods,models,andinfluentialfactors,andtoanalyzetheprospectsofPRCbridgepierseismicperformanceresearch.

CurrentResearchStatus

ThestudyofPRCbridgepiers'seismicperformancecanbedividedintothreeparts:experimentalresearch,theoreticalanalysis,andnumericalsimulation.Atpresent,mostoftheresearchisbasedontheexperimentalmethod,whichisaneffectivewaytoacquirethemechanicalpropertyofPRCbridgepiersduringearthquakes.Throughtheanalysisofexperimentalresults,itispossibletoimprovethedesignandconstructionofthebridges,reducingtheriskofnaturaldisasters.

ExperimentalResearch

WuJieetal.(2014)conductedaseriesofseismictestsonPRCbridgepiers,comparingtheseismicperformanceofstandardrectangularcross-sectionandcircularsectionpiers.Theresultsshowedthatthecircularsectionmodelhadsuperiorseismicperformancecomparedtotherectangularmodel.FengLeietal.(2016)investigatedtheseismicperformanceofPRCbridgepierswithahigh-strengthconcretecoreandfiberreinforcedpolymer(FRP)wrapping,concludingthatFRPwrappingcanimprovetheseismicresistanceofPRCpiers.Inaddition,manyotherresearchstudieshavefocusedontheseismicperformanceofPRCpierswithdifferentshapes,materials,andreinforcementforms,emphasizingtheinfluenceofaxialload,eccentricity,andshearforceonseismicbehavior.

TheoreticalAnalysis

ThetheoreticalanalysismethodisanotherwaytoresearchtheseismicperformanceofPRCbridgepiers.Themechanicsofmaterialsandfiniteelementmethod(FEM)areusuallyemployedinthisapproach.LiangTaizhongetal.(2014)proposedatheoreticalmodeloftheseismicbehaviorofcross-shapedPRCpiers,basedonthetransfermatrixmethod,thatcanevaluateseismicdisplacementanddamage.

ZhangXiaohuietal.(2015)utilizedthemechanicsofmaterialstoanalyzetheseismicbehaviorofPRCbridgepiersandfoundthattheseismicresistancecapacityofPRCbridgepierscanbeeffectivelyimprovedbyoptimizingthereinforcementform.

NumericalSimulation

NumericalsimulationapproacheshavetheadvantageofanalyzingthedynamicresponseofPRCbridgepiersunderearthquakes,whichisdifficulttoobtainwithexperimentalmethods.Thefiniteelementmethodandthediscreteelementmethodarethemostcommonlyusedsimulationmethods.TheFiniteelementmodels(FEM)cansimulatetheseismicresponseofPRCbridgepierunderdifferentseismicwavegroundmotions,load,andboundaryconditions.BianTianzhuetal.(2013)investigatedtheseismicbehaviorofPRCbridgepiersundersoilstructureinteraction,consideringthefrequencydomaincharacteristics

ofearthquakes.ChenShuhanetal.(2018)proposedanonlinearfiniteelementmodel(FEM)ofPRCbridgepiersthatcanassessthedeformation,stress,anddamageevolutionunderearthquakeloading.

InfluentialFactors

TheseismicperformanceofPRCbridgepiersisinfluencedbymanyfactors,includingseismicintensity,piershape,reinforcementstiffness,axialload,stirrupspacing,andboundarycondition.Amongtheseinfluencingfactors,theshapeofthepierhasasignificantimpactonitsseismicperformance.CircularPRCpiershavebetterdeformationcapacitythanrectangularpiers,whilerectangularpiershaveahigherbearingcapacity.Reinforcementstiffnesscanimprovetheseismicperformanceofpiers,buttoomuchstiffnessmayleadtobrittlefracture.Axialloadandstirrupspacingalsoaffecttheseismicperformanceofpiers.Highaxialloadreducesthelateraldeformationcapacityofpiers,whiledensestirrupspacingcaneffectivelyimprovethepier'sseismicperformance.

Prospects

IntheexistingresearchontheseismicperformanceofPRCbridgepiers,theexperimentalmethodistheprimaryresearchapproach,providingthemostreliablesourceofdata.However,thismethodisalsotime-consuming,costly,andhasrelativelylowefficiencywhenlarge-scalepiersrequiretesting.TheoreticalanalysisandnumericalsimulationmethodswillplayacrucialroleinthefutureresearchofPRCbridgepiers.Thesemethodsprovideamorein-depthunderstandingoftheseismicbehaviorofPRCpiersundervariousloadsandboundaryconditions.

Inthefuture,somekeyareasneedtobefocusedon,including:

AcomprehensiveevaluationsystemfortheseismicperformanceofPRCbridgepiersshouldbeestablishedbasedonexperimental,theoretical,andnumericalsimulationmethods.

TherelationshipsbetweentheparametersthatinfluencetheseismicperformanceofPRCbridgepiersshouldbeinvestigatedsystematically.

Applicationofadvancedtechnologiessuchassuper-fibermaterialand3DprintingtechnologyinthedesignandconstructionofPRCbridgepiersshouldbeexplored.

AunifiedstandardfortheseismicresistanceofPRCbridgepiersshouldbeestablishedandcontinuouslyimproved.

Conclusion

TheresearchontheseismicperformanceofPRCbridgepiershasenteredanewstageofdevelopment.Withth