基于接触问题的桩土相互作用机理

采用子结构凝聚自由度法推导出桩土接触问题的非线性有限元平衡方程，引入接触问题的约束条件，并通过增广拉格朗日乘子法对约束条件进行处理，得到数值计算的迭代格式，进而对桩土相互作用进行非线性数值计算，结果表明：数值计算结果与实测结果吻合较好，接触问题的引入可以合理地解释桩土相互作用的机理问题。

Mechanism of pile-soil interaction based on contact

The non-linear finite element equilibrium equation based on the contact interface is build by thefinite element method of sub-structure using cohesion degree of freedom, contact constraint which is dealt with by the augmented Lagrangian multiplier method, and pile-soil interaction effect was calculated by nonlinear numerical calculation. Results show that the general trend of numerical results and the measured results are the same. The introduction of the contact problem can reasonably explain the mechanism of pile-soil interaction effect.