Crack Propagation and Failure Analysis of Tunnel Lining Structures Under Several Conditions Using Peridynamic Method

Tunnel linings are critical components of underground infrastructure but are prone to cracking under complex, nonuniform loads. This study develops a nonlinear dual-parameter bond-based peridynamic (DB–PD) model to simulate crack initiation and propagation in concrete tunnel linings subjected to bias pressure, vault voids, pre-existing cracks, and varying lining thicknesses. The proposed model incorporates normal and tangential bond deformations, enabling accurate representation of the deformation and fracture behavior of concrete linings under tensile–shear and compressive–shear loading. The model is verified through tensile and four-point bending benchmarks and validated against a scaled bias-loading experiment. Numerical results reproduce the experimentally observed crack patterns and load–displacement responses. Parametric analyses reveal that bias angle, defect geometry, and lining thickness significantly influence failure mode and crack distribution.