Abstract:

In order to study the influence of jacking pipe on the existing sewage pipe, taking the No. 1 large rectangular jacking pipe at Shangdu Road Station of Line 4 of Zhengzhou Rail Transit. The finite element analysis model of the rectangular jacking pipe is established based on the Cambridge model; and the surface subsidence variation law of typical longitudinal section and cross-section in the influence range of jacking pipe construction is studied in the process of pipe jacking. The calculation results show that: (1) The overall effect of jacking pipe on surface deformation is settlement. (2) The combined action of lateral friction resistance of jacking pipe machine and jacking force of excavation section will cause surface uplift in a short time, and the uplift range is within 15-30 m behind excavation section. (3) The sewage pipeline mainly affects the distribution of the horizontal stress of the soil mass in the upper range of the tunnel side, and its influence on the horizontal stress of the soil mass in the tunnel depth range can be ignored, but it greatly reduces the vertical stress of the soil mass between the sewage pipe and the pipe joint, with a reduction range of 100 kPa.

Key words: rectangular jacking pipe, monitoring, settlement, jacking force, lateral friction resistance, finite element simulation