Analysis of pile behaviour in liquefying sloping ground
Analysis of pile behaviour in liquefying sloping ground
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DOI：
10.1016/j.compgeo.2009.08.001
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发表时间：
2010
影响因子：
5.3
通讯作者：
D. Liyanapathirana;H. Poulos
中科院分区：
文献类型：
--
作者：
D. Liyanapathirana;H. Poulos
本文概述了一种基于有限元方法研究倾斜地基中桩的性状的数值方法，它包括两个主要步骤。首先，采用基于有效应力的应力路径模型进行自由场地基响应分析，得到地基位移以及土层深度范围内退化土体的刚度和强度。然后对桩进行了动力分析。桩土界面处土的相互作用系数和极限侧压力由孔压累积引起的土体刚度和强度退化计算，远场土体由自由场地基响应分析计算的位移表示。将自由场地基响应分析中采用的应力路径模型预测的土的孔压产生和液化强度分别与模拟倾斜和水平地基条件下的松散砂土进行的一系列简单剪切试验进行了比较。此外，用于分析桩性状的数值程序也已使用离心机数据进行了验证，在横向扩展的倾斜地基中观察到了土壤液化。结果表明，尽管新方法相对简单，但仍能很好地估计桩的工作性状。
In this paper, a numerical procedure based on the finite element method is outlined to investigate pile behaviour in sloping ground, which involves two main steps. First a free-field ground response analysis is carried out using an effective stress based stress path model to obtain the ground displacements, and the degraded soil stiffness and strength over the depth of the soil deposit. Next a dynamic analysis is carried out for the pile. The interaction coefficients and ultimate lateral pressure of soil at the pile–soil interface are calculated using degraded soil stiffness and strength due to build-up of pore pressures, and the soil in the far field is represented by the displacements calculated from the free-field ground response analysis. Pore pressure generation and liquefaction strength of the soil predicted by the stress path model used in the free-field ground response analysis are compared with a series of simple shear tests performed on loose sand with and without an initial static shear stress simulating sloping and level ground conditions, respectively. Also the numerical procedure utilised for the analysis of pile behaviour has been verified using centrifuge data, where soil liquefaction has been observed in laterally spreading sloping ground. It is demonstrated that the new method gives good estimate of pile behaviour, despite its relative simplicity.