基于多场耦合的富水软土基坑降水研究

Research on Dewatering in the Water-rich Soft Soil Foundation Pit Based on Multi-field Coupling

为了研究止水排水结构对基坑渗流情况的影响,文章以苏州市相城区X352县道改扩建工程三标隧道基坑为工程背景,运用数值模拟软件,以Richards方程为基本物理场,对不同排水条件下的基坑渗流情况进行建模分析。研究结果表明:降水井对基坑周围地下水进行排水时,前20 h渗流水压力会下降很快,20 h之后会逐渐趋于稳定,同时降水井数量增多会明显减小渗流水压力。地下水位线变化与水压力变化一致,前期下降较快,最快可达到1 m/h左右,3 d后位置逐渐趋于平缓。

In order to study the influence of water stop drainage structure on the seepage of foundation pit,the tunnel foundation pit of X352 County Road reconstruction and expansion project in Xiangcheng District,Suzhou city was taken as the engineering background.The seepage of foundation pit under different drainage conditions is modeled and analyzed by numerical simulation software,and Richards equation is taken as the basic physical field.The results show that:When dewatering Wells drain groundwater around the foundation pit,the seepage water pressure will decrease rapidly in the first 20 hours and gradually become stable after 20 hours.Meanwhile,the increase of dewatering Wells will significantly reduce the seepage water pressure.The variation of groundwater level is consistent with that of water pressure,and it drops rapidly in the early stage,reaching about 1 m/h at the fastest,and gradually flattens out after 3 days.