地震作用下地铁站桥合建体动力响应分析

Dynamic Response Analysis of the Composite Structure of Subway Station and Urban Bridge under Earthquake

研究目的:为研究地铁车站与城市桥梁合建体的地震响应特征,本文结合工程案例,采用MIDAS GTS建立合建体结构的有限元模型,考虑土体与地下车站的相互作用,选取三种地震波,采用时程分析法对合建体结构进行地震反应计算,分析不同地震波对合建体结构的地震响应特征,获取地震作用下合建体结构的应力和变形规律。研究结论:(1)在设防地震作用下,地铁车站结构的最大层间位移角为1/1250,符合规范限值要求,具有良好的抵抗侧向变形能力;(2)地震作用下地铁车站结构的顶板加速度最大,其次为中板,底板加速度最小;(3)车站结构中柱与顶中底板连接节点处、侧墙与各层楼板相交处、结构顶中底板与侧墙相交位置附近等出现了较大内力响应,属于薄弱部位,需加强措施以提高结构的抗震能力;(4)本研究结论可为合建体结构的抗震设计提供借鉴和参考。

Research purposes:To study the seismic response characteristics of subway station and urban bridge composite structure,a finite element model of typical composite structure was established by MIDAS GTS.Considering the interaction between soil and underground station,three kinds of seismic waves are selected,and the seismic response of the joint building structure is calculated by time history analysis method.The seismic response characteristics of different seismic waves on the joint building structure are analyzed,and the stress and deformation laws of the joint building structure under earthquake are obtained.Research conclusions:(1)The maximum inter-story displacement angle of the composite structure is 1/1250,which meets the limit requirements of the code and has good resistance to lateral deformation.(2)The acceleration of the top plate is the largest,followed by the middle plate,and the acceleration of the bottom plate is the smallest under earthquake action.(3)There are large internal force responses at the joint between the middle column and the top and middle floor of the station structure,the intersection of the side wall and the floor of each floor,and the intersection of the top and middle floor and the side wall of the structure,which are weak parts.Therefore,it is necessary to strengthen the seismic measures to improve the seismic capacity of the structure.(4)The research results can provide technical reference for the seismic design of composite structures with subway station and urban bridge.