某深厚软土地层基坑支护方案优化研究

Study on Optimization of Foundation Pit Support Scheme in Deep Soft Soil

依托珠三角地区某深厚软土地层基坑工程案例,在采用排桩入岩方式基础上进行优化,探究排桩不入岩+裙边加固支护方式对基坑变形的影响。选取基坑中部具有代表性的一段,利用MIDAS/GTS NX有限元软件建立三维计算模型,对比排桩水平位移、坑底隆起、周边地表沉降、工程造价与施工难度,得出结论:排桩不入岩+适当深度的裙边加固能有效减少排桩水平位移、坑底隆起、周边地表沉降;加固深度超过一定范围后,对减小基坑变形效果不明显;优化方案工程造价和施工难度与原方案相仿,可为类似工程设计提供参考。

Based on the case of a deep soft soil foundation pit project in the Pearl River Delta region,this paper optimizes the method of row piles into the rock,and explores the effect of the row piles into the rock+skirt reinforced support method on the foundation pit deformation.A representative section in the middle of the foundation pit was selected,and a three-dimensional calculation model was established by using MIDAS/GTS NX finite element software to compare the horizontal displacement of row piles,uplift of the pit bottom,surrounding surface settlement,engineering cost and construction difficulty.Piling without rock and proper skirt reinforcement can effectively reduce horizontal displacement of piles,uplift of pit bottom,and surrounding ground settlement.After the depth of reinforcement exceeds a certain range,the effect on reducing deformation of foundation pit is not obvious;The cost and construction difficulty of the optimization scheme project are similar to the original plan,which can provide reference for similar engineering design.