Shear Behavior Of Fiber Reinforced Concrete Beams Reinforced With Basalt Frp Bars And Gfrp Stirrups

Abstract

Qatar suffers from a harsh environment in the form of high temperature that prevails almost all year round in addition to severe humidity and coastal conditions. This exposure leads to the rapid deterioration and the reduction of the life span of reinforced concrete (RC) infrastructure. With the developments in materials science, the advanced composites, especially fiber reinforced polymer (FRP) materials are becoming viable alternatives to the traditional construction materials. Having superior durability against corrosion, versatility for easy in-situ applications and enhanced weight-to-strength ratios compared to their counterpart conventional materials, FRPs are promising to be the future of construction materials. This study is focusing mainly on studying the shear behavior of basalt fiber reinforced concrete (BFRC) beams reinforced with basalt FRP bars and glass FRP (GFRP) stirrups. The experimental work comprises 14 beams of size 165 × 260 × 2000 mm. The beams were tested under four-point loading test by universal testing machine (UTM) until failure. The beams were reinforced with sand coated basalt FRP bars (BFRP) as a flexural reinforcement, in addition to the discrete, chopped basalt fibers, which were added to the concrete mix at two different volume fractions namely, 0.75%, and 1.5%. Two mixes with the aforementioned volume fractions were prepared and cured for 28 days before testing. The main parameters investigated in this study were the reinforcement ratio, the span to depth ratio and the volume fraction of basalt macro-fibers (BMF). Test Results showed a significant increase in the shear strength as the reinforcement ratio increases. In addition, using lower span to depth ratio resulted in an increase in the shear capacity. It has also revealed that using higher percentages of BMF enhanced the shear capacity, reduced the beam deflection, reduced the cracks width and propagation, and improve the beam ductility before failure.