地铁车站不同工况减压降水对环境的影响

Analysis of environment impact by dewatering confined water in different programs of subway station

为了研究不同工况下基坑降水对周边地下水位变化和地表沉降的影响,采用"现场抽水试验—水文地质参数反演—数值模拟计算"的一体化手段,运用MIDAS/GTS数值分析软件,对苏州地铁4号线某车站基坑降水建立了三维有限元分析模型,模拟计算不同的降水方案设计下所产生的基坑外地下水位变化和地表沉降,并对其进行对比分析。结果表明,不同的降水施工工况对周围环境的影响大小不一,在进行降水设计时需对不同降水工况设计下的环境影响进行预测和评估,使降水对周围环境影响最小,以实现降水方案设计的最优化。

To analyze the change of the groundwater level and land subsidence outside the foundation pit caused by dewatering in different conditions, the integrated mean of＂field pumping tests-the inversion of hydrogeological pa-rameters-numerical simulation＂ was adopted. The 3-D finite element analysis model of the deep pit dewatering of one station of Suzhou Metro Line No. 4 was established by using MIDAS/GTS to simulate and calculate the change of the groundwater level and land subsidence caused by different dewatering programs. The results show that the in-fluence on the surrounding environment caused by different dewatering programs is inconsistent, which should be predicted and assessed to minimize the effect of the surrounding environment to achieve the optimal design of dewa-tering program.