Physical and mechanical characteristics of new basalt-FRP bars for reinforcing concrete structures

• Physical and mechanical characterization of newly developed basalt FRP bars for concrete members.
• Durability of BFRP bars in harsh alkaline conditions simulating the concrete environment.
• Discussion of BFRP characterization and durability results and compare them against the requirements of FRP standards.

This paper introduces an experimental study that investigated the physical, mechanical, and durability characteristics of basalt fiber-reinforced polymer (BFRP) bars. Durability and long-term performance were assessed by conditioning the BFRP bars in an alkaline solution simulating the concrete environment (up to 3000 h at 60 °C) to determine their suitability as internal reinforcement for concrete elements. Thereafter, the properties were assessed and compared with the unconditioned (reference) values. In this study, three types of BFRP bars were investigated. The test results revealed that the BFRP bars had good mechanical behavior and could be placed in the same category as grade II and grade III GFRP bars (according to tensile modulus of elasticity). Their tensile strength, however, was higher than that provided by CAN/CSA S807-10 for CFRP bars. On the other hand, the BFRP bars showed poor alkali resistance and exhibited a remarkable reduction in mechanical properties due to the resin–fiber interface issues, which needs to be remedied to achieve the desired durability characteristics.