Characteristics Analysis of the Whole Process of Segment Circumferential Joint Dislocation during the Construction Period of Shield Tunnel

In the process of shield tunnel construction, the segment will appear under the action of external load joint opening and dislocation, in which the larger circumferential joint dislocation may cause water seepage and leakage of the segment adverse disease. Real-time monitoring of the ring joint dislocation is realized by tilting sensors connected in series to a wireless gateway, and the ring joint dislocation monitoring data are divided into the shield tail stage, grouting stage and stabilization stage according to the construction characteristics of the shield tunnels. Through the spatial and temporal characterization of the dislocation of the segment ring joint at different stages, the main conclusions are as follows: during the gradual contact between the segment and the tail of the shield, the axial load distribution of the segment along the tunnel is not uniform, resulting in the dislocation of the ring seams of the segment in the tail of the shield, relative to the dislocation of the segment in the tail of the shield along the radial axis of the tunnel to the center of the circle. The dislocation of the circumferential joint of the segment in the grouting stage is mainly caused by the loading difference of the neighboring segment rings. The dislocation in the tail of the shield is basically linear during the assembly period, and the dislocation can be controlled by considering the increase of the un-retracted jacking force. These findings can provide data support and verification for the analysis of ring dislocation mechanism and control research.