多维地震波作用下地铁车站及场地的地震反应

Response of Subway Station and Site to Multi-Dimensional Seismic Waves

研究了不同类型多维地震波作用下地铁车站及软土场地的地震反应特征。以上海软土场地条件下的某双层地铁车站为背景,采用有限元方法建立了描述场地土与地铁车站结构相互作用的二维非线性力学模型,其中利用等效线性化方法模拟了土的非线性。以不同类型基岩的多维(含水平向和竖向)地震波作为输入,运用ANSYS软件数值分析了软土场地中地铁车站结构及场地的地震反应,比较了不同类型地震波作用下地铁车站结构和场地地震反应的差异.算例结果表明:在长周期地震波作用下地铁车站结构的内力响应峰值以及场地地表的加速度响应峰值和位移响应峰值均明显大于普通地震波作用下的相应值;考虑竖向地震动时双层地铁车站底层中柱的柱底轴力较单一水平向地震动作用的情形有明显增大;地铁车站的存在使结构上覆土层加速度响应峰值和位移响应峰值有所降低.

For the study of seismic response characteristic of subway station and soft soil site under multi-dimensional seismic wave. Based on a two-story subway station in Shanghai soft site,the horizontal and vertical component of three bedrock seismic waves were chosen as the input to a 2D nonlinear soil-underground structure model which was created with ANSYS software. Analysis seismic response of the soil-underground structure under multi-dimensional seismic waves. This paper discussed the effect of the subway station on ground seismic response and dynamic response of the subway station under different types of seismic waves. The results show that： the subway station internal force peak response and the ground dynamic peak response under long-period seismic waves are much bigger than the results under normal seismic waves; the mid-pillar axial force increase greatly under multi-dimensional seismic waves; the existence of two-story subway station decrease acceleration and displacement peak response of the structure superjacent soil.