Abstract: Under the action of vertical earthquake, the overlying soil of the station is easy to be sheared and produce inertial force effect, which increases the load of the station structure and affects the ability of the key structure to resist external force and deformation. Referring to the section size of Dakai metro station in Japan, ABAQUS was used to establish 2D and 3D models of the metro station, and the nonlinear dynamic time-history analysis was carried out to obtain the relative displacement time-history response of the end of the central column and the distribution of vertical load on the central column and side walls. A 3D refined model of the central column was established. By applying the relative displacement response at the end of the central column obtained in 2D analysis as a load on the top surface of 3D refined model of the central column, the bearing ratio of the central column and the stress of the side wall under different section forms, as well as the failure mode of the central column after the earthquake were obtained. The research results show that: after the shear resistance of the overlying soil fails, under the vertical earthquake, its inertial force acts on the roof of the station structure; the coupling effect of the inertial force and the shear load generated by the side wall soil under the horizontal earthquake makes the middle column under the rectangular section suffer compression shear failure, and then withdraw from the force. The use of the arched section can alleviate the high axial compression ratio of the center column structure under earthquake action, change the slenderness ratio and improve the ductility of the central column, which keeps the central column in the state of bearing force after the earthquake and avoids the overall damage of the station structure.

Key words: tunnel engineering; geotechnical engineering; time-history analysis; inertial force effect; ductile design; seismic design; station structure

摘要： 竖向地震作用下，车站上覆土极易被剪坏而产生惯性力效应，增加车站结构负载，影响关键结构抵抗外力及变形的能力。参考日本大开地铁车站的截面尺寸，通过ABAQUS建立了地铁车站二维和三维模型，开展了非线性动力时程分析，获得了中柱端部的相对位移时程响应以及竖向荷载在中柱和侧墙上的分布情况；建立了三维中柱精细化模型，通过将二维分析中获得的中柱端部相对位移响应作为荷载施加在三维中柱精细化模型顶面上,获得了不同截面形式下中柱的承压比与侧墙的受力情况，以及中柱震后的破坏形态。研究结果表明：上覆土体的抗剪能力失效后，在竖向地震作用下，其惯性力作用于车站结构顶板，该惯性力与水平地震作用下侧壁土体产生的剪切荷载的耦合作用使矩形截面下中柱发生压剪破坏，进而退出受力;采用拱形截面可以缓解地震作用下中柱结构的高轴压比工作环境，同时改变了中柱的长细比，提高其延性，使其在震后仍保持着持力状态，避免了车站结构的整体破坏。

关键词: 隧道工程；岩土工程；时程分析；惯性力效应；延性设计；抗震设计；车站结构