Abstract:

Based on the research of large diameter slurry shield tunneling practice in Beijing railway underground diameter line project, this paper analyses and summarizes the key technologies of slurry shield tunneling, including cutting tools and geological adaptability of cutting tools, maintenance and repair of cutter head under hyperbaric condition, environmental protection of slurry treatment system, control of settlement of buildings and environmental impact in CBD, etc. The research and application of above technologies demonstrate that air cushion slurry shields have such advantages as high safety, good adaptability to water rich strata, small ground subsidence, controllable ground subsidence and low impact on the environment, etc. and that they can be used in long deep tunnels in complex geological conditions. 

Key words: Beijing Railway Underground Diameter Line, slurry shield, slurry treatment, ground deformation control, shield maintenance and repair, geological adaptability