Enhancing the Bond Durability of Basalt Fiber Reinforced Polymer Bars Using Basalt-Macro Fiber Reinforced Concrete

Abstract

This paper presents a study about the bond durability of basalt fiber reinforced polymers (BFRP) bars embedded in concrete incorporating basalt macro fibers (BMF) when conditioned in harsh saline environment at 60 °C. A total of 24 pullout specimens were tested to investigate the influence of concrete type (plain concrete and fiber reinforced concrete) and duration of conditioning (30, 60 and 90 days). The basalt-macro fiber reinforced concrete (FRC) incorporated BMF at 0.5% fiber volume fraction. The BFRP bars used had helically wrapped surface treatment. Moreover, the bond durability was assessed based on bond-slip behaviour, bond degradation, and service life predictions of bond strength retentions after 50 years of service life. The experimental results revealed that BFRP bars embedded in basalt macro FRC showed higher bond stiffness compared to those embedded in plain concrete. Additionally, BFRP bars embedded in basalt macro FRC showed slower bond degradation than their counterparts embedded in plain concrete. Finally, FRC increased the bond strength retentions of BFRP bars based on 50 years’ service life predictions when compared to plain concrete.