基坑开挖时邻近桩基性状的数值分析

基坑开挖时尤为关注的问题是土体侧向移动对邻近桩基的不利影响，土体的侧向移动使邻近桩基产生侧向位移和附加应力及弯矩，甚至可能使上部建筑物功能失效。采用土工有限元软件Plaxis 8.2对内支撑排桩支护基坑开挖过程进行数值模拟，分析了基坑开挖时对邻近桩基的各种影响因素，包括单排桩、双排桩在不同开挖深度、支护桩的刚度、桩基刚度、桩基距基坑开挖面距离、桩身的约束和桩长条件下桩身水平位移和弯矩的变化特性。

Numerical analysis of pile response due to braced excavation-induced soil lateral movement

The issue to which should be play attention is the detrimental effect of excavation-induced soil movement on adjacent piles. The additional deflections and bending moments of the pile shaft are generated due to soil lateral movement. This may lead to their superstructures distress or failure. The geotechnical finite element numerical analysis software Plaxis 8.2 is used to simulate the process of excavation; and the effects of many factors on the behaviors of adjacent piles are investigated, including excavation depth, stiffness of diaphragm wall, stiffness of pile, net distance between excavation and pile, constraint conditions of pile head, length of pile. The behaviors of lateral displacements and bending moments of piles are studied in detail.