1. Tianjin Research Institute for Water Transport Engineering, M.O.T., Tianjin 300456, China; 2. CCCC-Tianjin Port Engineering Institute Co., Ltd., Tianjin 300222, China; 3. Key Laboratory of Geotechnical Engineering of Tianjin, Tianjin 300222, China; 4. Geotechnical Research Institute, Hohai University, Nanjing 210098, China
Abstract：Shield tunneling in soft clay will inevitably lead to the disturbance of soil strata. The deformation caused by this disturbance and the resulting persistent deformation have been the research focus. The finite difference program FLAC3D is empbyed to accurately simulate the excavation process in soft soils. The consolidation deformation caused by the excess pore water pressure dissipation in the tunnel after a considerable period of formation of tunnel stratum is a major factor. The consolidation settlement is about 15% of the total settlement. The scope of soil subsidence induced by the consolidation is 1.4 times that by traditional undrained analysis methods.
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