文章编号:0258-2724(2024)02-0323-09DOI:10.3969/j.issn.0258-2724.20220091考虑冲刷效应的大跨桥梁地震-风-车-桥耦合振动分析王亚伟1,朱金2,郑凯锋2,苏永华1,郭辉1,李永乐2(1.中国铁道科学研究院集团有限公司,北京100081;2.西南交通大学土木工程学院,四川成都610031)摘要:为研究冲刷效应对地震与风联合作用下大跨桥梁动力响应的影响,在已建立的地震-风-车-桥耦合振动分析模型基础上,利用p-y曲线(p为土阻力,y为变形)折减法考虑不同冲刷深度的桩土荷载-位移关系,根据桩土荷载-位移关系和冲刷深度更新桩基的侧向支撑刚度和长度,从而考虑了冲刷效应对大跨桥梁动力响应的影响,并将模型应用到江顺大桥冲刷效应的分析研究中.研究结果表明:基础冲刷减弱了地基土对结构的侧向约束,从而降低结构的自振频率,侧向振型的自振频率最大降低6.01%;在运营车辆和风荷载作用下,基础冲刷对结构的振动响应影响很小;在地震发生后,基础冲刷会增大结构的横向振动,结构的横向位移响应极值最大增大9.1%,横向位移响应谱也相应增大,而对结构的竖向振动影响很小;基础冲刷可能减小车辆横向加速度的响应,车辆的横向加速度响应极值最大降低7.7%,对车辆的竖向振动影响很小.关键词:冲刷效应;p-y曲线;大跨桥梁;地震-风-车-桥系统;耦合振动中图分类号:U447文献标志码:ACoupledVibrationAnalysisofEarthquake-Wind-Vehicle-BridgeforLong-SpanBridgesConsideringScouringEffectWANGYawei1,ZHUJin2,ZHENGKaifeng2,SUYonghua1,GUOHui1,LIYongle2(1.ChinaAcademyofRailwaySciencesCorporationLimited,Beijing100081,China;2.SchoolofCivilEngineering,SouthwestJiaotongUniversity,Chengdu610031,China)Abstract:Inordertostudytheinfluenceofthescouringeffectonthedynamicresponseoflong-spanbridgesunderthecombinedactionofearthquakeandwind,basedontheestablishedcoupledvibrationanalysismodelofearthquake-wind-vehicle-bridge,thep-ycurve(pisthesoilresistanceandyisthepiledisplacement)reductionmethodwasusedtoconsidertheload-displacementrelationshipbetweenthepilesandsoilwithdifferentscourdepths,andthelateralsupportstiffnessandlengthofpilefoundationwereupdatedaccordingtotheload-displacementrelationshipandscourdepth.Thus,theinfluenceofthescouringeffectonthedynamicresponseoflong-spanbridgeswasconsidered,and...