不同场地条件下地连墙对地铁车站结构地震动力响应的影响  

Influence of the diaphragm wall on the dynamic responses of subway station structures under different site conditions

作　　者：赵密[1] 贾智富 昝子卉[2] 黄景琦 杜修力[1] ZHAO Mi;JIA Zhifu;ZAN Zihui;HUANG Jingqi;DU Xiuli(Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education,Beijing University of Technology,Beijing 100124,China;Guangzhou Metro Design&Research Institute Co.,Ltd.,Guangzhou 510010,Guangdong,China;Beijing Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]广州地铁设计研究院有限公司,广东广州510010 [3]北京科技大学城市地下空间工程北京市重点实验室,北京100083

出　　处：《地震工程学报》2023年第2期270-278,295,共10页China Earthquake Engineering Journal

基　　金：国家自然科学基金项目(U1839201);国家重点研发计划项目(2018YFC1504305);北京市自然科学基金项目(JQ19029)。

摘　　要：地铁车站多采用基于地下连续墙(简称:地连墙)的明挖施工方法,施工后地连墙作为永久结构与车站共同受力。在车站结构抗震分析中,考虑到地连墙可能对结构抗震的有利作用,出于安全储备考虑通常忽略地连墙的存在,但地连墙对车站结构地震响应的影响规律和机理仍有待深入研究。以某典型两层三跨地铁车站结构为对象,基于近场波动有限元方法并结合黏弹性人工边界条件,开展有无地连墙情况车站结构地震响应特性对比研究,揭示不同场地条件下地连墙对车站结构地震响应的影响规律,阐明地连墙的影响机理。研究结果表明:地连墙具有减小车站结构总体层间位移效应,有利于侧墙和底层中柱抗震,但同时放大了顶底板与侧墙连接处的弯矩和正应力;地连墙对结构顶层中柱端部及中跨中板板端的内力和正应力的影响与场地条件相关,坚硬和中硬场地条件下具有减小效应,软弱场地下略有增大作用。上述结构响应规律的原因可归结为地连墙增加了结构侧墙刚度,降低了结构整体侧向变形,但限制了侧墙的弯曲变形,导致结构顶底板与侧墙交接处的弯曲变形和内力增大。The open excavation method has always been adopted for subway station construction,wherein the diaphragm wall serves as a supporting structure in the foundation pit,following which the diaphragm wall continuously operates with the subway structure.In previous studies,the diaphragm wall was assumed to have a positive impact on earthquake resistance,and it was usually neglected in the seismic analysis of subway structures.However,the influence mechanism of the diaphragm wall on the seismic performance of subway structures must be further studied.Based on the finite element method of near-field wave motions and the viscous-spring artificial boundary condition,the dynamic responses of a typical two-story and three-span subway station structure with and without the diaphragm wall were compared and analyzed.Furthermore,the influence characteristics and mechanisms of the diaphragm wall on the seismic responses of subway station structures under different site conditions were investigated.Numerical results indicated that the diaphragm wall,which can reduce the overall inter-story displacement of a station structure,is beneficial to the seismic resistance of the side wall and the middle column in the bottom layer.However,the diaphragm wall also magnifies the bending moment and normal stress at the connection between the roof and floor and the side wall.The influence of the diaphragm wall on the internal force and normal stress of the middle column end in the top layer and the middle-span plate end of the structure is related to the site condition.In detail,it has a decreasing effect under hard and medium hard site conditions and a slightly increasing effect under soft site conditions.A possible reason for the response mechanism is that the diaphragm wall increases the lateral stiffness of the structure,thereby reducing the lateral deformation of the station structure.However,the diaphragm wall restricts the side wall deformation,thus increasing the bending moment and internal force at the connection between the roof and f

关 键 词：车站结构 地连墙 不同场地条件 土-结构动力相互作用 地震响应 

分 类 号：TU352[建筑科学—结构工程]