Abstract: The theory of vibration of pile foundation in layered soil is applied to the analysis of vibration of a single pile in liquefied soil. The dynamic interaction between pile and soil is described by Winkler spring-damper model. The amplification factor of the displacement at pile’s head under earthquake excitation is obtained by initial parametric method and transfer matrix method, in which the liquefied phenomenon of soil is considered. The result indicates that the softening coefficient, thicknesses of soil layers, flexural stiffness and mass density per unit length of the pile have great influence on amplification factor of the displacement at pile’s head.

Key words: vibration and wave, vibration of single pile, liquefied soil, transfer matrix method, softening coefficiency

摘要： 将层状土中桩基振动相关理论扩展应用到考虑土层液化的桩基振动的研究，借助于Winkler弹簧-阻尼器模型描述液化土和非液化土与桩基之间的动力相互作用，利用初参法和传递矩阵法得到了地震激励作用下考虑土层液化的桩基桩顶位移放大因子。结果表明，液化后的土层软化系数、土层厚度、桩身抗弯刚度和桩身线质量密度等对考虑液化的桩基振动特性有较大的影响。

关键词: 振动与波, 单桩振动, 液化土, 传递矩阵法, 软化系数