Numerical Investigation of the Segmental Lining Performance for a Shield Tunnel

The performance of segmental linings in China's Yellow River Crossing Tunnel is studied as a case study, and a complete three-dimensional numerical model is developed for the segmental joint to perform a bending test and reproduce the joint rotational performance. Besides, an improved three-dimensional solid-spring model together with a straightforward two-dimensional beam-spring model are presented for the segmental lining to take the influences of the joint into account. The bending test shows that the rotation stiffness of joints presents complex and nonlinear characteristics. The segmental lining simulation reveals that the segmental joint has little impact on the axial forces of the lining. However, the bending rigidity of the segmental lining corresponding to the joint location is weakened, which leads to discontinuous stress distribution, decreased bending moments and increased deformations. According to the comparison, the proposed three-dimensional solid-spring model excluding contact has the advantage of mesh generation, and it is capable of reproducing the three-dimensional segmental lining effects. The proposed two-dimensional beam-spring model combined with the calculation methods of all the spring stiffnesses is an effective and further simplified method for the segmental lining modeling, which incorporates the influences of the joint and staggered format.