Repair and Reinforcement of Concrete Bridges Based on Cement-Based Composite Materials

At present, epoxy resin is almost used as a binder in bridge reinforcement, but there are some drawbacks due to the huge difference in mechanical properties and temperature incompatibility between it and concrete. Cement-based composites show obvious multi-crack cracking characteristics and strain hardening behavior in the process of stress and have better mechanical properties and durability than traditional cement materials, and have been successfully used in many practical projects. In this paper, the cement-based composite material is used as the concrete beam member of the bridge deck continuous material, and its mechanical properties are characterized and compared with the traditional cement slurry material properties. The results show that the ductility of cement-based composites is significantly affected by the fiber content. When the volume ratio is less than or equal to the critical volume rate, the ductility increases gradually with the increase of fiber content. The maximum value of the plastic strain at the initial crack is greater than that of the concrete beam member using cement mortar as the bridge deck continuous material, and the crack resistance of the bridge deck continuous structure is significantly improved. The addition of cement-based composites can significantly increase the cracking load of the test beams. Under the same load conditions, the crack resistance of the continuous structure of the cement-based composite bridge deck is better, and local cracking is less likely to occur.