Integrated High-Performance Concrete Beams Reinforced with Hybrid BFRP and Steel Bars

Abstract

The flexural behavior of concrete beams reinforced with a combination of basalt fiber–reinforced polymer (BFRP) bars and steel bars is investigated herein. Five hybrid BFRP and steel bar RC beams, one pure BFRP-RC beam, and one pure steel-RC beam, were designed based on the principle of equal stiffness and subject to four-point bending tests. The main study parameters included the bar type, ratio of the steel reinforcement area to the BFRP reinforcement area (As/Af), and BFRP bar diameter. The results of the four-point bending tests showed that the hybrid-RC beams had a lower ultimate load and larger ultimate deflection with the increase in As/Af. The tested beams had similar stiffnesses before yielding; the five hybrid-RC beams exhibited an obvious postyielding stiffness as well, which contributes to a higher reserve in both strength and deformability. Comparisons between the experimental values and predicted values of ultimate capacity, deflection, and crack width using design models are also presented herein.