基于FLAC3D的地铁车站深基坑变形规律分析

Research on deformation law of subway station foundation pit based on FLAC3D

运用FLAC3D有限差分软件模拟合肥市地铁2号线天柱路车站深基坑工程的施工,通过不同工况下计算结果与实测数据的对比分析,发现深基坑的挖深不断增大,围护结构的水平位移也不断增大,且最大水平位移出现的位置逐渐下移,呈两端小,中间大的"抛物线"形分布,基坑周边地表沉降近似呈"凹槽形"分布。虽然数值模拟计算结果与实测结果在数值上存在一些偏差,但总体变化规律基本相同,可初步验证FLAC3D模拟能够对基坑开挖前的围护结构设计以及施工监测方案的制定提供参考依据。

bIn this paper, the FLAC3D finite difference software is used to simulate the construction of deep foundation pit of Ti- anzhu road station of Hefei Metro Line 2, compared the calculation results under different conditions with the measured data. With the excavation depth of deep foundation pit increased, the horizontal displacement of retaining structure increase gradual-ly, and the maximum horizontal displacement moves down gradually, which has the feature of ^parabolaw shape distribution： small at both ends, big at the middle. Approximately rtgroovew distribution of surrounding ground settlement outside the pit. Al-though the results of numerical simulation and measured results has some deviation in value, the overall change law is basically the same, which shows that FLAC3D numerical simulation could be used to provide reference to the design of pre-excavation retaining structure and the formulation of monitoring programs to provide reference.