Research on the transverse collaborative working performance of hollow slab bridges enhanced by channel steel and prestressed CFRP tendons

The hinge joint is critical for the transverse connection of hollow slab bridges and is highly susceptible to damage due to increasing traffic volumes and vehicle loads. To enhance the transverse collaborative working performance (TCWP) of hollow slab bridges, a hinge joint reinforcement technique by installing transverse channels at the bottom of the hollow slab and vertical prestressed CFRP tendons in the hinge joints is proposed in this study. The enhancement effects of four types of reinforcement on the TCWP of hollow slab bridges were investigated through scaled-down model tests and numerical simulations. The test results showed that compared to other reinforcement methods, RHS-C-C-60 (combined reinforcement of channel steel and prestressed CFRP tendon) demonstrated the best TCWP enhancement, as evidenced by the most uniform distribution of lateral load distribution (LLD) and rebar strain. The force characteristics of the bolts and channel steel were optimized using localized thickening of the channel steel through numerical simulation. The numerical results showed that the prestress reduced the maximum stress in the channel steel and the axial tension in the bolts on both sides of the CFRP tendons under the localized thickening measurement. The research presented in this paper provides a valuable reference for the reinforcement of hinge joints in hollow slab bridges.