Influence of Prestressing Effect on Vehicle-Bridge Coupling Vibration Response of Simply Supported Girder on Medium Speed Maglev Line
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/s2 to 0.44 m/s2.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/s2 to 0.76 m/s2 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.