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This research studies the shear behavior of concrete beams reinforced with hybrid-wires FRP bars with minimum stirrups. Eight shear beams were tested under a four-point static load up to failure. The beams were divided into three groups according to different parameters: the type of main reinforcement (steel bars, glass fiber reinforcement bars and hybrid wires bars), the ratio between the area of steel wires to the total area of the main reinforcement bar, which consists of steel wires and GFRP (25%steel wires, 50%steel wires and 75%steel wires) and the steel fibers volumetric ratio (0.4%, 0.8% and 1.2%). The experimental study shows that using hybrid wires bars as main reinforcement to overcome low modulus of elasticity of FRP bars leads to improve cracking, ultimate shear strength and ductility of the tested beams, and transfers the mode of failure of these beams into a more ductile than FRP beams. It is important to note that; increasing the ratio of steel wires to the total area of the main reinforcement bar from 25% to 75% leads to increase the ultimate shear capacity by approximately 64%. A high value of shear strength is obtained when the ratio is increased to reach 75%, and it can be used as main reinforcement instead of steel reinforcement. Furthermore, increasing the steel fiber content from zero to 1.2% volume fraction produces an increase in shear capacity and improves the mode of failure. |
