引水隧洞的浅埋暗挖法施工

The Method of Tunnel-undercutting with Shallow Overburden for Constructing Water Diversion Tunnel

南水北调中线北京城区段引水隧洞总长12.64 km,设计流量30 m3/s。工程具有以下特点:①隧洞通过Ⅴ类松软地层;②隧洞上覆盖层簿,仅为8 m～12 m;③洞线上城区建筑物密集;④洞线周围地下管网密集。针对上述情况,工程采用了浅埋暗挖法施工。文中具体介绍了施工方法及施工安全监测。

The total length of the water diversion tunnel in Beijing urban section of middle main line of South-to- north Transfer Projet is 12.64km. Its design discharge is 30 m^3/s. This project has following features： （1）The tunnel passes through soft and weak strats of V grade,（2） The overburden above tunnel is thin, only from 8m-12m,（3） The urban＇s buildings are dense above the tunnel line, （4） The underground pipes are concentrative around tunnel. Aiming at the actual project situation, the method of tunnel-undercutting with shallow overburder for construting this water diversion tunnel is adopted. In the paper the concrete construction method and construction safety su- pervision are introduced.