Abstract The breakage of segmented lining has become one of the common problems of shield tunnels. The breakage mechanism of segmented lining in shield tunnels was discussed using the finite element method based on fracture mechanics from three levels,i.e.,a single segment,two segments with a joint and the whole lining ring. The bearing capacity and the failure mode of a single segment were found to be mainly affected by the boundary conditions. The failure of joints was in the form of opening at one side and crushing at the other side and eventually leading to the destruction of whole lining ring. The continuous joint model was found to be close to the real situation in modeling the mechanic behavior at a low load condition. The disconnection of two segments at the joint at a high load,and even the ultimate bearing capacity condition were not able be to be captured in the simulation,neither the concrete crushing around the joint. Therefore,the modeling of joint is the key in order to more accurately predict the bearing capacity and deformation of a whole lining ring.
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