基于FLAC^(3D)的太原车站基坑变形影响因素研究

Research on Deformation Factors of Foundation Excavation in Taiyuan Subway Station Based on FLAC^(3D)

针对太原地铁首开工段明挖基坑所存在的地质条件复杂、漫滩特征显著、开挖面积大、施工工况复杂等问题,采用FLAC3D数值模拟的方法对车站开挖全过程进行仿真,研究了该种河漫滩地质条件下不同支护参数(插入比、钢支撑间距、预应力设置值)对太原漫滩地区明挖基坑的影响规律:墙后地表变形表现为明显的凹槽形,整体沉降量偏小;基坑变形随着插入比的增加而减少,但其减小速率逐渐变缓;基坑变形随钢管撑间距的增大呈近线性增大的趋势;预应力的提高对减小基坑变形影响甚微。

In order to solve problems of open-dug foundation excavation in beginning process of Taiyuan subway station with complex geological conditions,floodplain,and large excavation area and complex construction conditions,FLAC-（3D） is used in the whole process of deep foundation excavation.Features of foundation excavation under different supporting parameters such as in floodplain area are found as following：ground surface deformation behind enclosure wall shows concave type with little settlement,the deeper the insertion is,the smaller and slower the deformation of foundation excavation is.The deformation of foundation excavation tends to be linear larger,along with the increase of steel support space.Prestress improvement has few influences on deformation of foundation excavation.