降雨条件下膨胀土地层基坑支护结构的变形分析

Deformation Analysis of Foundation Pit Retaining Structure of Expanded Soil Layer under Rainfall Conditions

由于受到降雨等天气的影响,膨胀土地层基坑的支护结构在开挖过程中形成一定的膨胀土附加应力场作用,导致支护结构出现一定程度的变形,降低了基坑支护结构的安全性。文章以合肥地铁5号线四川路站基坑工程为研究背景,运用Midas GTS/NX有限元软件对基坑开挖过程进行数值模拟计算,得到加载水平膨胀力作用下的桩体变形和支撑内力数值计算结果,再将其与现场监测数据进行对比,发现两者变化基本吻合,基坑支护结构在膨胀力的作用下变形值有一定程度的增加,为以后同类型的基坑支护结构设计提供了一定的参考。

Due to the influence of rainfall and other weather,the supporting structure of the foundation pit of the expanded soil layer forms a certain additional stress field of the expanded soil in the excavation process,resulting in a certain degree of deformation of the supporting structure,which reduces the safety of the foundation pit supporting structure.Taking foundation pit construction of Sichuan Road Station of Hefei subway line 5 as the research background,this paper numerically simulated the excavation process of the foundation pit by Midas GTS/NX finite element software and then obtained the numerical calculation results of pile deformation and internal force of support under the action of loaded horizontal expansion force.The obtained numerical calculation results were compare with the field monitoring data,finding that their changes basically coincided with each other,and the deformation value of the foundation pit support structure under the action of the expansion force increased to a certain extent,which provided a certain reference for the future design of the foundation pit support structure of the same type.