近远场地震动作用下地铁车站结构地基液化效应的振动台试验

开展了近场和远场地震动作用下3跨3层地铁车站结构地基液化效应的振动台模型试验，测试了地铁车站结构的加速度、应变、水平位移反应和地基土孔隙水压力、加速度、震陷及其作用于模型结构侧墙的动土压力反应。分析和总结了地铁车站结构地基液化效应特征，结果表明：模型结构对其周围地基土孔隙水压力场的分布有明显影响，结构两侧和底部地基土中的孔压峰值小于相同深度离结构较远地基土中的孔压峰值；地基土中孔压的消散速度自下而上呈逐渐减慢的趋势；地震动作用过程中，模型结构产生向上的相对运动，强地震动作用时模型结构上浮现象明显；模型结构侧墙受到的动土压力随深度增大而减小，输入地震动特性对动土压力的大小有显著影响。

Shaking table test on ground liquefaction effect of soil-metro station structure under near-and-far field ground motions

Based on a metro station structure of three stories and three spans at a liquefiable ground, a series of shaking table tests is conducted, in which the acceleration response, strain response and horizontal displacement of the station structure itself are tested. And the pore water pressure, acceleration and seismic subsidence of the foundation soil are also measured. This paper mainly analyzes the dynamic response rules of the foundation soils under the influence of liquefaction effect and it also summarizes the development law of pore water pressure for liquefaction ground around station. Moreover, seismic subsidence characteristics as well as the dynamic soil pressure on the side walls are concluded. The results indicate that the structure has an obvious effect on the distribution of the pore water pressure field. At the same depth of soil, the peak of the pore water pressure of each measured point near the structure is less than that far from the structure. The dissipation rate of the pore water pressure is gradually slowed down from bottom to top. The structure has a movement upward relative to the foundation in the process of earthquake; and the floating phenomenon is obvious under strong ground motion. The dynamic earth pressure of the side walls is decreasing with increased depth; and the earthquake characteristics have a significant influence on the dynamic earth pressure.