Bond properties between GFRP bars and hybrid fiber-reinforced concrete containing three types of artificial fibers

Abstract This study investigated the bond properties and stress-slip relations between glass-fiber-reinforced plastic (GFRP) bars and hybrid fiber-reinforced concrete (HFRC) containing carbon, aramid and polypropylene fibers, and explored the effects of fibers-volume fraction, bar diameter, anchorage length and surface configuration. A total of 48 samples, including 36 HFRC samples with embedded GFRP bars and 12 ordinary concrete (OC) samples with embedded GFRP bars, were manufactured and subjected to pullout tests. The test results indicated that the bond behavior between the GFRP bars and HFRC was significantly improved by the cooperative effects of the carbon, polypropylene and aramid fiber. A bond-slip constitutive model for the GFRP bars embedded in both HFRC and OC was established and had a good agreement with the testing results.