橡胶支座-地铁车站减震结构的动力响应及关键设计参数研究

Dynamic responses of rubber bearing subway station seimic absorption structures and the key design parameters

基于地下结构布设隔震支座可有效控制结构地震反应,以某实际两层两跨地铁车站为研究对象,建立了橡胶支座布设于地铁车站结构的三维全时程动力分析模型,探讨了橡胶支座关键设计参数-水平刚度比对多层地铁车站减震结构地震响应的影响,并进一步分析了在最佳水平刚度比条件下减震结构的动力响应。研究结果表明:(1)中柱布设橡胶支座后,中柱内力及位移均有不同程度的减小,表现出良好的减震效果;(2)水平刚度比的变化对减震结构中柱的动力响应结果影响显著,对结构侧墙的动力响应结果影响较小,且水平刚度比会对中板的变形模式产生影响,综合考量,建议最佳水平刚度比的范围为0.06~0.08;(3)在最优水平刚度比条件下,结构中柱位移减震率最高可达85%,且中柱及侧墙始终处于安全工作状态,达到了破坏模式可控的效果。

Placing isolation bearings according to underground structures can effectively control structural seismic responses.An actual two-story,two-span subway station was taken as the research object,and a three-dimensional full time dynamic analysis model was established for analysing the placement of rubber bearings in subway station structures.The influence of the key design parameter of rubber bearings,horizontal stiffness ratio,on the seismic responses of multi story subway station seismic absorption structures were explored,and the dynamic response of the seismic absorption structure under the optimal horizontal stiffness ratio was further analyzed.The research results show that:(1) after installing rubber bearings on the central column,the internal force and displacement of the central column are reduced to some extent respectively,exhibiting good shock absorption effects.(2) The change in horizontal stiffness ratio has significant impact on the dynamic response results of the columns in the seismic absorption structure,but has small impact on the dynamic response results of the side walls of the structure,and the horizontal stiffness ratio will have impact on the deformation mode of the middle plate.With comprehensive consideration,it is recommended that the optimal range of horizontal stiffness ratio is 0.06-0.08.(3) With the optimal horizontal stiffness ratio,the maximum displacement damping rate of the central column in the structure can reach 85%,and the central column and side walls are always in a safe working state,achieving the effect of controllable failure modes.