柔性承台下群桩及刚性桩筏基础的竖向振动分析

Analysis of axial vibration of pile groups with flexible caps and pigid riled-raft foundations

基于简化的群桩动力计算模型,采用有限元子结构方法和薄层法,提出了与工程实际情况更为接近的完全埋入、部分埋入群桩和刚性桩筏基础的计算方法。分析了层状地基中不同激振频率条件下,承台板厚度、桩间距对于群桩动力阻抗的影响,研究了不同承台板厚度条件下群桩阻抗的分布规律。通过与传统刚性承台下群桩动力特性的比较分析,验证了本模型的合理性。

In this paper,a simplified analytical method is developed for the axial harmonic response of totally embedded,partially embedded pile groups and rigid piled-raft in layered soil deposits.Based on BDWF model,finite element sub-structure method is used to setup the dynamic model of cap-pile groups which can precisely simulate kinetic interaction and inertial interaction.A comprehensive parameter study focuses on the influence of caps' height and pile spacing on pile groups dynamic response,and then points out the definition of rigid cap in practical design.The solution of present method is compared with that of traditional simplified method(rigid and massless cap solution),and it is demonstrated that the present method can predict the pile groups dynamics response more reasonable and reliable.