南京长江隧道到达井基坑降水设计与施工

南京长江过江隧道梅子洲明挖段基坑主要包括引道段和盾构到达井,基坑规模大,地下水丰富,地质条件复杂,使得该基坑降水成为整个过江隧道众多关键技术之一。本次在抽水试验基础上设计了基坑降水方案,考虑到周边环境简单,采取了＂坑外降水为主,坑内降水为辅＂的降水方式,实际结果表明：降水方案合理可行,未对周边环境造成过大的影响。

Design and Construction of Dewatering in Foundation Pit of Vertical Shaft in Nanjing Changjiang Tunnel

The foundation of Meizizhou open excavation section mainly consisted of approach channel and shield excavation well.Due to the large-scale excavation,abundant groundwater and complex geological conditions,dewatering in foundation pit became one of many key technologies.Because of the simple circumjacent environment,the scheme of dewatering in foundation pit was designed based on the pumping test.It was proved that the scheme was rational and feasible without unfavorable influence to the environment.