盾构长距离下穿湖底的设计方案研究

Study on the Design of Long Distance Tunneling under Lake

苏州轨道交通1号线星港街站～会展中心站区间隧道长约2 350 m,其中约1 850 m下穿金鸡湖,是苏州地区第一条湖底盾构隧道,同时也是目前国内最长的湖底盾构隧道。该区间隧道所处的地层为含有微承压水的粉细砂地层,且隧道最小覆土厚度仅为7.4 m,隧道结构与防水设计难度高,施工风险大。结合该工程,对地铁区间长距离下穿水域的设计方案进行了探讨。

The distance between Xinggang road station and Exhibition Center station on Suzhou subway line 1 is about 2 350 meters,among which 1850 meter goes under Jinji Lake.It is the first shield tunnel under lake in Suzhou as well as the longest shield tunnel under lake in China.The soil layer within the section is made of micro water bearing fine sand with a minimum earth covering of only 7.4 meters.Great difficulties and risks are involved in the design and construction of tunnel structure and water prevention.In light of the project,design program for long subway tunnel under water is discussed.