SOME PARAMETERS AFFECTING SHEAR BEHAVIOR OF HIGH STRENGTH FIBER REINFORCED CONCRETE BEAMS LONGITUDINALLY REINFORCED WITH BFRP REBARS

Abstract

This research studies the shear behavior of high strength fiber reinforced concrete beams longitudinally reinforced with Basalt Fiber Reinforced Plastic (BFRP) bars with and without stirrups. Eight high – strength reinforced concrete beams were tested. Steel fibers and stirrups were used either separately or together as shear reinforcement. The test variables were steel fiber content (Vf)% with and without minimum shear reinforcement. All beams were tested under a four point static loading up to failure to investigate the shear behavior of high strength fiber reinforced beams reinforced with BFRP rebars. The shear span-to-depth ratio (a/d) was kept constant at 2.5. Crack pattern and mode of failure, cracking and ultimate shear strength and mid-span deflection are presented to provide useful insights on the shear failure mechanism of such beams. The experimental study shows that addition of steel fiber improves cracking, ultimate shear strength and ductility of the tested beams, and transfers the mode of failure of these beams into a more ductile one. The test results were compared with different proposed equations and design guidelines. Imam M. A, gave a reasonable equation to predict the shear strength of fiber concrete beams reinforced with BFRP bars with or without stirrups. Also the proposed equation predicted relatively well the ultimate shear strength of the experimental results than other predictions.