柔性群桩与地基相互作用的非线性分析

对桩侧土采用非线性荷载传递函数 ,桩端土采用线性荷载传递函数 ,同时考虑桩周土所分担的荷载对桩基荷载传递规律的影响 ,首次将增量荷载传递矩阵法与微分方程的近似解法———子域法相结合 ,推出了刚性承台下柔性群桩与地基非线性相互作用的系列近似解析算式。得出了如下结论 :刚性承台下 ,中桩、承台边缘桩及角桩的桩侧摩阻力沿深度的分布规律不完全相同 ,且各桩侧摩阻力发挥的程度也不一样 ,角桩侧摩阻力发挥最大 ,边中桩次之 ,中桩侧摩阻力发挥最小。

NONLINEAR ANALYSIS OF THE INTERACTION KETWEEN FLEXIBLE GROUP PILES AND THE SURROUNDING SOIL

Using a nonlinear load transfer function for the side soil and a linear load transfer function for the end soil of a pile, this paper introduces a method combining the incremental load transfer matrix method and the approximate analytical differential equation solution method. The proposed method provides a new approach for analyzing the nonlinear interaction between a flexible pile group under rigid platform and the surrounding soil. It is found that, under rigid platform, the longitndinal distributions of the skin frictions are different for the middle pile, side piles and corner piles,and the degree of effectiveness of the skin friction is largest for the corner piles,second for the side piles,and smallest for the middle pile.To verify the results, a static load test on a nine-pile group under a rigid platform is conducted.It is found that the results from the proposed method match very well with the test results and are better than those from the finite element method.