Flexural Performance Study of Basalt-Fiber-Reinforced Polymer Bar Basalt-Fiber-Reinforced Concrete Beams

Abstract

The utilization of Fiber-Reinforced Polymer (FRP) rods to strengthen concrete beam structures can enhance their ultimate load-carrying capacity and mitigate steel reinforcement corrosion damage. However, a prominent issue with BFRP (Basalt FRP) rod reinforcement in flexural members is its lack of yielding behavior, which can lead to catastrophic brittle failure without any preventive measures. Therefore, this study aims to enhance the ductility of concrete by introducing a specific quantity of basalt fiber, thereby reducing the hazards associated with the brittle failure of this composite structure. This experiment focuses on two main variables: the inclusion rate of basalt fiber and the type of longitudinal reinforcement and conducts four-point static bending tests on four BFRP bar BFRC (Basalt-Fiber-Reinforced Concrete) beams. Results showed that the inclusion of fibers resulted in a delayed initiation of vertical cracks and a reduction in the severity of beam failure, thereby enhancing structural safety and reliability. When the basalt fiber inclusion rate was 0.2%, the cracking load and ultimate load of the beam increased by 18.42% and 8.27%, respectively. Furthermore, compared to traditional RC beams, BFRP bar BFRC beams showed a 58.27% increase in ultimate load capacity. A cracking moment calculation model for BFRP beams is proposed and subsequently validated through the utilization of existing experimental data.