Abstract:

The adaptive design of doubleshield TBM in Qingdao Metro Line No.2 is carried out to fit the special construction condition of urban metro tunnel with rock geology. The module design is used; the auxiliary gripper is equipped on front shield matching with stabilizer; the segment is transported to segment erector by crane; the shuttle conveyor is used for mucking of backup system; and the laser guiding system with double laser targets is adopted for smallradius boring. By adopting the abovementioned technologies, the TBM assembling, launching, boring, mucking, station passing through, smallradius boring and TBM disassembling in tunnel have been successfully finished; therefore good application effect has been achieved. The feasibility of the doubleshield TBM used in Qingdao metro tunnel has been verified by analyzing boring parameters of TBM, deformation of lining and settlement of ground surface.

Key words: doubleshield TBM, metro tunnel, modular design, auxiliary gripper, segment hanging system, shuttle conveyor, laser guiding system