Peridynamics Simulation of Cracked Tunnel Linings Reinforced with FRP

In order to study the crack-resistance performance of fiber-reinforced composite (FRP) reinforced tunnel cracked lining, based on the peridynamics theory, a peridynamics simulation method for FRP reinforced concrete structures is established by introducing the interface weakening criteria. Four-point bending tests of FRP reinforced concrete beams are conducted to verify the simulation method. The problem of FRP reinforced tunnel cracked lining is modeled and analyzed to explore the influence of FRP reinforcement width and layers on the reinforcement performance of various cracked linings. The results indicate that: Interfacial debonding is the main failure mode of FRP reinforced cracked lining. The width and number of layers of FRP reinforcement are positively correlated with the reinforcement performance. Nevertheless, when the reinforcement width exceeds 2/3 of the arch bottom and the number of layers exceeds 2, the structural reinforcement performance does not significantly improve. In addition, the distribution and depth of cracks have a significant impact on the reinforcement performance of FRP, and the reinforcement effect of mid-span cracks is significantly better than that of eccentric cracks. Moreover, when the height ratio of mid span cracks is 1/5, the global damage index of FRP reinforcement lining decreases by 40.3%, significantly improving the crack resistance performance of the structure.