基坑开挖和堆载对邻近建筑物基础的影响模拟

A finite element numerical simulation analysis of effect on adjacent piles induced by excavation and soil surcharge

基坑开挖与堆载工程引起的土体位移对邻近建筑物桩基的影响越来越受到学者和工程师们的重视。依托上海某工程发生的楼房倒塌工程事故,利用二维数值分析方法,对基坑开挖和堆载造成的既有建筑物基础的影响进行模拟,分析了不同工况对既有建筑物桩身的水平位移的影响,并进行了评价分析。研究结果表明,基坑开挖时,基坑外侧一定距离施加荷载有助于控制挡土墙的水平位移;在既有建筑物一侧开挖基坑,而在另一侧堆载会使桩身中部弯矩增大,存在断裂风险。

The pile response to soil movements induced by adjacent excavation has attracted more and more attention of engineers and scholars.Based on an engineering accident of building collapsing in Shanghai,a simulation of the influence of the excavation and surcharge on the foundation of existing building is summarized by two-dimensional numerical analysis method.The effects of different engineering to pile’s displacement are investigated in detailed,and some suggestions for the design and construction are given.The study results show that:the displacement of the retaining wall can be advantageously reduced by the external loading,in addition,it will increase the bending moment in the middle of the pile and cause fracture risk with the increase of the external loading.