中文摘要：

利用薄层元素法和有限单元法,对层状地基中桩筏基础的动力阻抗进行了分析。比较了桩筏基础和群桩、筏板基础的水平阻抗、竖向阻抗以及摇摆阻抗,并讨论了地基的层状结构对桩筏基础的动力阻抗的影响。结果表明：桩筏基础的水平阻抗和筏板基础的比较接近,而竖向阻抗、摇摆阻抗和群桩的比较接近。地基的层状结构使得桩筏基础的阻抗发生波状变动,在低频区域表现为刚度增大,阻尼减小。

英文摘要：

Dynamic impedance functions of a pile-raft foundation in layered soil are studied by using the thin layered element method and the finite element method. The horizontal, vertical and rocking impedance functions of the pile-raft foundation are compared with those of a pile group and raft foundation. The effects of layered soil on the impedance functions of the pile-raft foundation are also analyzed. The results show that the horizontal impedance of the pile-raft foundation is approximate to that of the raft foundation, but the vertical and rocking impedance are approximate to those of the pile group. The layered soil causes undulations in the impedances of the pile-raft foundation, which are characterized by the increase in the stiffness and the decrease in the damping in the low-frequency range.