土-地铁车站及其上盖结构体系地震反应分析

为研究地震作用下地铁车站及其上盖结构体系的地震反应特征，本文以一典型的地铁车站及上盖结构体系为背景，采用ABAQUS软件建立土-地铁车站及其上盖结构体系的三维有限元模型，利用等效线性化方法考虑土的非线性，以不同类型的单向地震波和双向地震波（含水平向和竖向）作为输入，对土-地铁车站及其上盖结构体系进行了地震反应分析，比较了不同类型地震波作用下地铁车站及其上盖结构体系地震反应的差异，探讨了竖向地震动效应和转换梁刚度的影响．本文的算例结果表明：与普通基岩波和El-centro反演波输入相比较，在长周期基岩地震波作用下地铁车站及其上盖结构体系的内力响应和位移响应均最大．这一地铁车站及其上盖结构体系的薄弱部位位于地铁车站底层第2列、第3列柱的柱端和侧墙与底板连接处．竖向地震动对地铁车站及其上盖结构体系中柱的轴力响应值有较大影响．对于本文的动力计算工况，适当弱化转换梁刚度可降低上盖结构层间位移角的动力响应值．

Seismic Response of the System of Soil and Subway Station with Upper Structure

To investigate the seismic response characteristics of the system of subway station with upper structure, a case study of a typical subway station with upper structure was conducted. A 3D numerical model of the system of soil and subway station with upper structure was established by the finite element code ABAQUS. Equivalent linearization method was used for soil nonlinearity. Different types of single dimension and double-dimension (horizontal and vertical) ground motions were applied to the model. The different seismic responses under various ground motions were compared with each other. The influences of the stiffness of transfer beams and the vertical ground motions were discussed. The results show that compared with the common bedrock wave and El-centro inverted wave, the internal force response and displacement response of the subway station and its upper structure system are the largest under the long-period bedrock seismic waves. The dangerous points of the subway station and its upper structure system are located at the ends of the second and the third columns and the junction between the bottom plate and the side wall at the bottom floor of the subway station. Vertical ground motion has a great influence on the axial force response of the column in the subway station and its upper system. The use of a smaller cross-section transfer beam reduces the response of the displacement angle between the layers of the upper structure.