Performance evaluation of basalt fibre-reinforced polymer rebars in structural concrete members–a review

The corrosion of steel reinforcement has become a critical problem in reinforced concrete (RC) structures and has led to shortening the service life of the structures. Due to the non-corrosive characteristics of basalt fibre-reinforced polymer (BFRP) rebars, to replace steel reinforcement with BFRP rebars in RC structures, researchers have focused their attention on investigating the performance of BFRP rebars in various concretes. Reinforcing of concrete elements is one of the most important applications in the construction of RC structures. Bond, flexure, and shear are important structural parameters that affect the performance of RC members significantly. Therefore, the objective of this paper is to summarize and analyse the reported findings of the bond strength, bond durability, flexural, and shear performance of BFRP rebar in various RC members. BFRP rebars exhibited almost similar bonding behaviour with better durability performance compared to steel reinforcement and other fibre-reinforced polymer rebars. The RC beams with pure BFRP rebars exhibited large wider cracks and higher deflections due to a lower Young’s modulus of BFRP rebars. To overcome these effects, approaches like hybrid reinforcement, pre-stressing of BFRP rebars, introduction of ECC layers in tension zone, and application of steel fibre-reinforced concrete have been investigated and the test results were satisfactory. BFRP rebars provided smaller amount of shear strength as a stirrup member in RC beams. ACI 318-92 guidelines recommend designing the pure BFRP RC beams as over-reinforced sections to reduce deflections, large and wider cracks of the beams. Further research on BFRP structural elements is required to develop practical design standards and guidelines.