Shaking Table Test and Theoretical Analysis of the Pile-Soil-Structure Interaction at a Liquefiable Site
Shaking Table Test and Theoretical Analysis of the Pile-Soil-Structure Interaction at a Liquefiable Site
复制标题
液化场地桩-土-结构相互作用的振动台试验及理论分析
DOI：
10.1002/tal.1513
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Lu Zheng
中科院分区：
文献类型：
--
作者：
Li Peizhen;Yang Jinping;Lu Zheng
桩基础广泛应用于高层建筑的支撑，桩将地基荷载传递给承载力和刚度较高的土层。这一过程改变了地震活跃区，特别是在可液化场地的桩-土-结构系统的动力特性。通过对高层建筑群桩基础液化土的振动台试验，研究了群桩基础液化过程及桩、土、结构的动力响应。土壤由两层组成：上层为粘土层，下层为饱和砂土。这些层被放置在一个柔性容器中，该容器由埃尔森特罗地震事件和上海基岩波在不同水平激发。试验结果表明，随着输入加速度幅值的增大，孔压比逐渐增大。液化砂土对高频振动有滤波作用，对低频振动有放大作用。随着激振力的增大，桩身接触压力和应变幅值增大，峰值加速度放大系数减小。桩-土-结构相互作用结构的地震反应一般小于刚性基础结构的地震反应。
Pile foundations are widely used to support high‐rise buildings, in which piles transmit foundation loads to soil strata with higher bearing capacity and stiffness. This process alters the dynamic characteristics of the pile–soil–structure system in seismically active areas, especially at a liquefiable site. A series of shaking table tests on liquefiable soils in pile group foundations of tall buildings were performed to evaluate the liquefaction process and dynamic responses of the pile, soil, and structure. The soil was composed of two layers: the upper layer was a clay layer and the lower layer was saturated sand. These layers were placed in a flexible container that was excited by El Centro earthquake events and Shanghai Bedrock waves at different levels. The test results indicate that the pore pressure ratio is gradually enhanced as the amplitude of the input acceleration increases. The liquefied sand has a filtering effect on the vibration with a high frequency and an amplified effect on the vibration with a low frequency. With increased excitation, contact pressure and strain amplitudes of the pile increase, whereas the peak acceleration magnification coefficient decreases. The seismic responses of a structure with pile–soil–structure interaction are generally smaller than those on a rigid foundation.