The power tunnel of Tibet road in Shanghai is the most difficult pipe-jacking project in Chinawith long distance and large diameter. The tunnel crosses through Suzhou river, underground pipelines and areaof dense buildings, especially the underground passage of subway and the existing subway line 2, so it's vitalimportant to protect the surrounding environment when the pipe-jacking is constructed. The deformation ofground surface and the existing tunnels during the construction of curved pipe-jacking is studied with 3D finiteelement methods. First, the calculated results are analyzed and compared with the measured data in site to verifythe correctness of the 3DFEMmodel. Second, there are many factorswhich can affect ground displacementwhencurved pipe-jacking is constructed. Among these factors, slurry sleeves' qualities, soil pressure on the face ofpipe-jacking, slurry injection pressure and earth resistance are discussed on the basis of finite element simulation.Then, the deformation of existing tunnels of subway line 2 is studied. Finally, the ground displacement formulaof curved pipe-jacking is discussed.The results show that the continuity of slurry sleeves and the pressure of theface are very important factors to ground surface deformation during the construction of curved pipe-jacking.The ground displacements induced by curved pipe-jacking are not larger than those of linear pipe-jacking if theslurry sleeves around pipe are good and continual. Because of additional earth resistance, the maximum of theground surface deformation perpendicular to pipe axis is at the side of the center of the pipe-jacking curve, andthe distance of deviation depends on the radius of pipe-jacking curve.
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