Abstract:
Taking the engineering example of the interval tunnel of Xiang′an Administrative Center Station and Pubian Station of Xiamen Metro Line 3 under-passing utility tunnel of drainage culvert and pipeline trench, the Midas-GTS finite element software is adopted to simulate the structure deformation and ground surface settlement response characteristics of the utility tunnel during shield tunnel construction. Effective technical measures for controlling existing structure deformation and ground surface settlement are proposed. Research results show that for the pipeline trench going first parallel to then above the tunnel, maximum deformation occurs on left side of the left and right lines of the tunnel; while for the culvert straddling symmetrically above the tunnel, maximum deformation occurs in the middle of the left and right lines. Within certain range of shield arriving and departing from the structure, ground surface differential settlement rate demonstrates sudden change; the time point T1 when surface sudden increase deformation occues can be used as the key time node for settlement control.