一、前言 土—桩—基础—结构系统的地震相互作用分析可以按下列三步依次进行: (1)求不计上部结构惯性的基础运动。这一所谓的基础输入运动包括平移分量和旋转分量; (2)确定桩帽平移、旋转和平移旋转耦合振动的动力阻抗函数(弹簧、阻尼器); (3)计算支承在上述弹簧、阻尼器上的上部结构的地震反应,其基底输入为由第一步所获得的基础运动。 对于上述分析的每一步骤,都已提出了多种可供选择的计算方法,包括有限元 I. INTRODUCTION Earthquake-pile-foundation-structure system seismic interaction analysis can be carried out in the following three steps in sequence: (1) The basic motion of inertia of the superstructure is not calculated. This so-called basic input motion includes a translational component and a rotational component; (2) A dynamic impedance function (spring, damper) that determines the translational, rotational, and translational rotational coupling vibrations of the pile cap; (3) Calculation support on the aforementioned spring, damper On the seismic response of the superstructure, its base input is the basic movement obtained from the first step. For each step of the above analysis, a variety of alternative calculation methods have been proposed, including finite element