Bond Strength of Basalt FRP Bars with Different Surface Treatments to Plain and Fiber-Reinforced Concrete

Abstract

The current study presents an investigation on the influence of the surface texture of the reinforcing bar and the addition of macro fibers to concrete on the bond strength of basalt fiber reinforced polymers (BFRP) bars. Two types of BFRP bars were tested, one with a sand-coated surface and the other with a ribbed surface. In addition, a plain concrete mix was prepared as a reference to evaluate the effect of adding basalt (B) and polypropylene (PP) fibers to the concrete mix. The testing results showed that the ribbed BFRP bars resulted in a significant enhancement in the bond strength over the sand-coated BFRP bars. The average bond strength in the ribbed bars was recorded as 37.17 MPa, whereas it was recorded as 16.44 MPa in the sand-coated bars. Also, the addition of PP fibers to concrete revealed a slight increase in bond strength of 6.5% compared to plain concrete. On the other hand, the addition of B fibers decreased the bond strength by 11% compared to the plain concrete samples.