考虑承台刚度的复合桩基承载性状分析

Analysis on bearing capacity of piled raft foundation in consideration of rigidity of pile-cap

以桩筏基础为对象,考虑承台刚度的影响,将桩、土及承台视为一个相互作用的复合桩基体系,通过Goodman接触单元模拟桩土界面接触摩擦作用和土体的非线性特性,采用三维有限元数值方法对桩筏基础进行系统地分析,研究桩筏基础的承载机理。首先验证了Goodman接触单元模拟在桩土接触中的可行性,然后研究了桩筏基础中桩顶反力、桩身轴力及桩侧摩阻力的分布规律与特性,最后考虑了承台刚度对桩筏基础的影响,得出了一些有意义的结论,为复合桩基的理论分析及工程设计提供理论依据和借鉴。

In the piled raft, the pile, soil and pile cap were considered as an interacting foundation system in consideration of rigidity of pile - cap. In order to make a numerical simulation of the friction between the soil and the piles as well as nonlinear character of soil, the Goodman contact element is used. The piled raft and it＇ s bearing mechanism were studied by the three - dimensional finite element numerical analysis. At first, this article verifies the feasibility of applying the Goodman contact element into the pile - soil contact, then this essay summarizes the reaction force of pile block, axial force and side resistance of each pile, as well as the effect of piled raft in consideration of rigidity of pile - cap. Finally, some results would be profitable and helpful to the theoretical analysis and the engi- neering design.