铁路桥梁减隔震支座仿真设计研究

Study on Simulation Design of Seismic Isolation Bearing for Railway Bridge

为探究铁路桥梁双曲面球形减隔震支座设计仿真时正常使用位移间隙对结构地震内力的影响规律,以某高烈度震区大跨连续梁桥工程为例,开展了全桥地震非线性时程反应分析,对比分析了减隔震支座初始位移间隙不同滑移位置下结构的地震内力和位移响应结果,研究结果表明减隔震支座现状模拟方法较不安全。为减少抗震方案比选阶段双曲面球形减隔震支座仿真计算的成本,采用不考虑减隔震支座正常使用位移对双曲面球形减隔震支座仿真进行了简化研究,对比了现状模拟方法与简化模拟方法地震响应差异,论证了简化模拟方法的可行性以及设计要点,并针对双曲面球形减隔震支座不同设计阶段提出了建议,为类似工程开展减隔震设计提供了借鉴。

In order to explore the influence law of the normal displacement clearance of the double spherical seismic bearing on the seismic internal force of the structure during the design and simulation,a long-span continuous girder bridge in the area with high seismic intensity was taken as an example to analyze the seismic nonlinear time history response.The seismic internal force and displacement response results of the structure under different initial sliding positions of the seismic bearing were compared and analyzed.The research shows that the current simulation method is not safe.In order to reduce the cost of simulation calculation of double spherical seismic bearing at the stage of seismic scheme comparison,the simulation of double spherical seismic bearing was simplified without considering the normal use displacement of the bearing.The difference of seismic response between the current simulation method and the simplified simulation method were compared to demonstrate the feasibility and design points of the simplified simulation method.The suggestions for dfferent design stages of double spherical seismic bearing were given which provide reference for similar projects to carry out seismic design.