预应力效应对中速磁浮线路简支梁车-桥耦合振动响应的影响  

Influence of Prestressing Effect on Vehicle⁃Bridge Coupling Vibration Response of Simply Supported Girder on Medium Speed Maglev Line

作　　者：李波[1] LI Bo(China Railway Fourth Survey and Design Institute Group Co.Ltd.,Wuhan 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,武汉430063

出　　处：《铁道建筑》2024年第2期62-66,共5页Railway Engineering

基　　金：国家重点研发计划(2021YFB2600401);中铁第四勘察设计院集团有限公司科技研发项目(2022D001)。

摘　　要：以长沙磁浮线路简支梁桥为研究对象,建立考虑不同预应力效应的磁浮线路简支梁桥车-桥耦合振动模型,分析预应力效应对中速磁浮线路车-桥耦合振动响应的影响。结果表明:预应力效应的变化对桥梁动力响应影响明显,预应力增加显著加剧桥梁竖向振动加速度,预应力由0.67P0(P0为张拉控制应力)增加到1.33P0时,桥梁跨中竖向最大加速度从0.21 m/s^(2)增至0.44 m/s^(2);车速增加会加剧预应力效应的影响,对桥梁竖向振动加速度的影响尤为明显,车速由20 km/h增加到200 km/h时,在1.00P0作用下,桥梁跨中竖向最大加速度从0.15 m/s^(2)增至0.76 m/s^(2);箱壁局部变形对车-桥耦合竖向振动响应有显著影响,预应力导致的箱壁局部变形不可忽略。Taking the Changsha maglev line simply supported girder bridge as the research object,a vehicle-bridge coupling vibration model of maglev line simply supported girder bridge considering different prestressing effects was established,and the influence of prestressing effects on the vehicle-bridge coupling vibration response of medium speed maglev line was analyzed.The results show that the variation of prestress effect has a significant impact on the dynamic response of the bridge.The increase of prestress significantly intensifies the vertical vibration acceleration of the bridge.When the prestress increases from 0.67P0(P0 is the tension control stress)to 1.33P0,the maximum vertical acceleration at the mid span of the bridge increases from 0.21 m/s^(2) to 0.44 m/s^(2).The increase of vehicle speed will aggravate the influence of prestress effect,especially on the vertical vibration acceleration of the bridge.When the speed increases from 20 km/h to 200 km/h,the maximum vertical acceleration increases from 0.15 m/s^(2) to 0.76 m/s^(2) under the 1.00P0 condition.The local deformation of box wall has significant influence on vehicle-bridge coupling vertical vibration response and the local deformation of box wall caused by prestressing cannot be ignored.

关 键 词：中速磁浮线路 简支梁桥 数值模拟 车-桥耦合振动 预应力效应 动力分析 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]