水平层状饱和场地地震响应分析的等效线性化方法

采用饱和土层和半空间精确的动力刚度矩阵，建立了求解P波、SV波斜入射情况下水平层状饱和场地地震响应的一维等效线性化分析方法。将饱和场地退化至干土场地进行方法验证，并将该文结果与二维有限元程序FLUSH结果进行对比，验证了该文方法的准确性。以天津市区某典型饱和场地为例，分别比较了P波和SV波入射情况下饱和场地线性、非线性地震响应之间的差别，以及饱和场地、干土场地非线性地震响应之间的差别，并讨论了入射角度和透水条件等因素对地面运动加速度峰值的影响，总结了饱和场地非线性地震响应的一些基本规律。

EQUIVALENT LINEAR ANALYSIS OF SEISMIC RESPONSE OF HORIZONTALLY LAYERED FLUID-SATURATED POROELASTIC HALF-SPACE

By adopting exact dynamic stiffness matrices of a fluid-saturated soil layer and a half-space, an 1-D equivalent linear analysis method is proposed to solve the seismic response of a horizontally layered fluid-saturated poroelastic half-space due to the incident of inclined P and SV waves. By degenerating saturated soil to dry soil, and by comparing the degenerated results with those by 2-D finite element program FLUSH, the accuracy of the method is verified. Through taking a typical fluid-saturated site in Tianjin city as a numerical example, this paper compares the linear and nonlinear seismic responses of the site, and the nonlinear seismic responses between a fluid-saturated site and a dry site due to the incident of P and SV waves, and discusses the effects of incident angle and permeable boundary conditions on the peak ground acceleration of the fluid-saturated site. Some basic laws about the nonlinear seismic response of a fluid-saturated site are summarized.