A state-of-the-art review: Shear performance of the concrete beams reinforced with FRP bars

FRP-reinforced concrete widely used in engineering with excellent salt resistance is a potential alternative to steel-reinforced concrete in harsh environments. This paper reviews a comprehensive overview of the shear performance of the concrete beams reinforced with FRP bars on shear failure characteristics, factors affecting the shear capacity, calculation of shear capacity, shear durability, fire resistance, and future research needs. The results indicated that the low elastic modulus and the reduction of mechanical properties in the bending portion of the FRP stirrups make it difficult to limit the cracking of the concrete, resulting in an insufficient shear performance and a significant size effect of the beam. Fibers can effectively improve the post-cracking shear performance of the different types of concrete. Also, replacing FRP stirrups with FRP strips and FRP grids is a potentially feasible method to improve the mechanical properties of FRP stirrups at the bending portion. Moreover, the use of ECC, FRP grid, and TRC to strengthen and skin the bottom and sides of the beam and the application of prestressing are potential ways to reduce the size effect and improve the shear capacity. Furthermore, artificial intelligence technology and self-learning are recommended to be carried out while continuously replenishing the database dynamically to provide data support for the study of the shear resistance of concrete members reinforced with FRP bars. Finally, the quantitative relationship between material degra-dation and component mechanical performance degradation needs further research.