Dynamic Performance and Damage Assessment of Tunnel Infrastructure under Surface Rock Blasting

Underground tunnels are essential to urban transportation networks but can be affected by surface explosions during construction. Tunnel damage depends on factors such as blast distance, TNT weight and layout, tunnel structure, and rock properties. Understanding tunnel performance under such conditions is crucial for blast-resistant design. This study uses 3D finite element models with a coupled Eulerian–Lagrangian solver to simulate explosive loads. The models are validated against experiments on reinforced concrete slabs and soil under air and surface blasts. The study details nonlinear material properties for rock, concrete, and blast loads then examines tunnel strain responses, dynamic performance, and cumulative damage under different blast scenarios. The findings offer valuable insights for managing rock blasting activities near tunnels.