桩-土三维等厚度接触单元模型及其工作性状

本文根据桩侧土的剪切非线性性质，推导了桩-土三维等厚度接触单元的单元刚度矩阵，并以某工程实际的层状地基为例，研究讨论了在竖向荷载作用下桩长、桩端土层压缩模量及桩体弹性模量等因素对此等厚度接触单元工作性状的影响。结果表明，本文所采用的接触单元模型能够很好地模拟在竖向荷载作用下桩与桩侧土体之间滑移破坏的发展情况。

Pile-soil 3-D constant thickness contact interface element model and its characteristics

The element stiffness matrix of pile-soil 3-D constant thickness contact interface element is deduced according to the non-linear stress feature of the soil surrounding the pile.A layered foundation is used as an example to discuss the effect of pile length, compressive module of pile bottom soil and pile elastic module on the features of the contact interface element. The results show that the contact interface element can simulate the development of the slip between piles and surrounding soils under vertical load.