为了深入研究基坑开挖过程中超挖厚度的不同对基坑围护结构的内力和位移及周边环境的影响,运用岩土有限元软件Midas GTS模拟了在不同超挖厚度下深基坑开挖过程,从而得到在不同超挖厚度下基坑围护结构内力、变形及地表沉降的分布规律。计算和分析结果表明超挖厚度对基坑围护结构的内力和位移及地表沉降产生了较大影响,尤其是围护结构水平位移及地表沉降;在超挖的影响下桩和锚索不能同时起到维护的作用,使得超挖下桩后土体变形较大,基坑的稳定性处于不利的状态。研究结果将有助于提高深基坑设计水平,为类似工程的设计、施工和研究提供必要参考。

In order to study the influence of over-excavation thickness on internal force and displacement of retaining structure as well as surrounding environment, we simulate the excavation process of deep foundation pit by using Midas GTS software, hence obtaining the distributions of internal force of retaining structure, deformation and subsidence in the presence of different over-excavation thicknesses. The analysis results show that over-excavation thickness has big influence on internal force and displacement of retaining structure and ground subsidence, especially on horizontal displacement of retaining structure and ground settlement. Furthermore, affected by over-excavation, the maintaining effects of pile and anchor could not act in the same time, and soil deformation under the pile is big, which is unfavorable to the stability of foundation pit. Through the research, we can improve the design of deep foundation pit, and the results can be referenced for the design, construction and research of similar projects.