Serviceability and Ultimate Load Behavior of Concrete Beams Reinforced with Basalt Fiber-Reinforced Polymer Bars

The flexural properties of eight 200 x 300 mm (8 x 12 in.) concrete beams reinforced with basalt fiber-reinforced polymer (BFRP) reinforcing bars were investigated. The beams were reinforced with four different sizes of BFRP (10, 13, 16, and 25 mm). The flexural reinforcement ratios rho(f) ranged from 1.43 to 10.70 times the balanced ratio rho(fb). The beams were divided into three categories with low, moderate, and high rho(f). As expected, all the beams failed by crushing of the concrete in the top compression fiber. Higher rho(f)/rho(fb), to some extent, has a better effect on reducing the deflection than increasing the beam's ultimate strength. The strain compatibility equation per ACI 440.1R-06 was conservative in predicting the ultimate flexural strain in the BFRP bars and the ultimate moment capacity. The effective moment of inertia (I-e) prediction model recommended by ACI 440.1R was the least conservative among other models when compared with the experimental I-e.