The effect of the force between rings of large-diameter shield tunnels on the segmental cracking in weak stratum

Large-diameter shield tunneling in weak strata has the risks of segment floating, segment cracking and seepage, affecting the durability of the tunnel structure. In this paper, the statistical analysis of the cracks of a large-diameter shield tunnel segment was carried out, and the thickness of the force transmission liner was studied. The experiment showed that the average number of cracks per ring was the smallest when using a 3mm liner. Based on the structural characteristics of the segment, four types of stresses, namely simple support of segment boss, double-sided cantilever, single-point cantilever and two-point cantilever, and it is verified through on-site statistics, which has certain guiding significance for crack prevention.