软土地区基坑支护安全性分析与评价研究

Safety Analysis and Evaluation of Foundation Excavation Support in Soft Soil Area

为了研究软土地区不规则形状基坑支护及施工安全性问题,以上海市黄浦区某基坑场地为例,基于场地工程地质特征进行支护及施工方案设计,综合选取了钻孔灌注桩+三轴水泥土搅拌桩止水的支护形式,并从时空效应考虑采用分区开挖支护的方式,最后使用有限元模拟软件对基坑支护施工对周边环境的影响程度进行分析。研究结果表明:分区开挖结合钻孔灌注桩+三轴水泥土搅拌桩止水的支护形式可以很好的控制基坑变形及降低对相邻建筑物、管线的影响程度,预测变形值均在规范的允许范围内,但在施工期间须加强监测工作。

In order to study the problem of irregular shape foundation excavation support and construction safety in soft soil area,a foundation excavation site in Huangpu District of Shanghai was taken as an example. The support and construction scheme design was based on the geological characteristics of the site engineering,and the bored pile was selected comprehensively. + Triaxial cement-soil mixing piles are used to stop water,and the method of zoning excavation and support is considered in terms of spatio-temporal effects. Finally,finite element simulation software is used to analyze the influence of foundation excavation support construction on the surrounding environment. The results of the study indicate that the form of support for excavation combined with cast-in-situ bored piles + triaxial cement-soil mixing piles can effectively control the deformation of the foundation excavation and reduce the influence on the adjacent buildings and pipelines. The deformation values are predicted. Within the allowable scope of the regulations,but monitoring must be strengthened during construction.