北京地铁四号线隧道辐射井降水施工实践

在交通复杂、人口密集的城市中心区修建地下隧道,如何降低地下水,是影响施工的关键问题。文中以北京地铁四号线黄庄—中关村区间隧道施工降水为例,从辐射井降水原理着手,介绍了一套占地面积小、降水控制范围大、疏干效果好的施工降水方法。实践证明:竖井采用沉井工艺,水平井采用水力双壁钻杆反循环工艺,可达到快速高效降水的目的,且造价较井点降水节约30%。

Construction Practice of Tunnel Radiation Well Dewatering of Beijing Metro No.4 Line

Underground water reduction is the key issue for underground tunnel construction in urban central area with complex traffic and dense population.Taking tunnel dewatering construction in Huangzhuang-Zhongguancun Section of Beijing Metro No.4 Line as an example,this paper introduces a dewatering method with small land area,large control range and good draining effect from the principle of radiation well.It is proven from practice that shaft with sinking process and horizontal well with hydraulic double-wall drill pipe reverse circulation process can achieve rapid and effective dewatering and save 30 % compared with well point dewatering.