高速铁路列车制动力对简支梁桥地震碰撞效应影响研究

Influence of train braking force on seismic pounding effect of a high-speed railway simply supported bridge

以高速铁路三跨简支梁桥为例,采用ANSYS软件,建立了碰撞有限元模型,模型中考虑了地基变形和支座非线性的影响,并用Kelvin模型来模拟邻梁碰撞;根据规范和已有试验结果建立了高铁桥梁列车制动力模型,进行了高速列车制动力与EL-Centro地震波作用下的碰撞效应分析,探讨了列车制动力对简支梁桥地震碰撞效应的影响。研究表明:列车制动力可增大桥墩的墩底剪力,增大邻梁或梁台间距,增大邻梁最大碰撞力和碰撞次数,加剧固定支座的破坏;影响程度与列车制动力和地震力的方向、桥墩刚度有关。因此在高铁简支梁桥抗震设计时,有必要考虑将列车制动力与地震力进行组合,开展碰撞效应分析。

Taking a high-speed railway 3-span simply supported bridge as a study object,its collision finite element model was established with the software ANSYS. In this model,the foundation deformation and the nonlinearity of bearings were considered,and Kelvin model was used to model the collision between adjacent beams. The train braking force model was built with the codes and the existing testing results. Finally,the pounding effect under the action of the train braking force and EL-Centro earthquake wave was analyzed,the influence of the train braking force on the seismic pounding effect of the simply supported bridge was explored. The results showed that the train braking force makes the shearing force at the bottom of piers larger,the distance between the adjacent beams increase,the maximum impact force and the collision number increase,and the destruction of the restrained supports worse; the influence level is related to the direction between the train braking force and the seismic load,and the stiffness of piers; therefore,investigating the pounding effect of the bridge under the combination action of train braking force and seismic load is very necessary for the aseismic design of high-speed railway simply supported bridges.