Shear Resistance Of Reinforced Concrete Deep Beams With Opening Strengthened By CFRP Strips

Abstract

Carbon fiber reinforced polymer (CFRP) as an external reinforcement is used extensively to address the strength requirements related to flexure and shear in structural systems. In this paper, the behavior and performance of reinforced concrete deep beams with opening strengthened with externally bonded CFRP strips failed in shear is presented. The experimental work includes testing eight reinforced concrete deep beams. The variables considered in the experimental study include the effect of fiber orientation (90º or 45º CFRP strips with respect to beam longitudinal axis), the effect of using longitudinal CFRP strips with vertical CFRP strips and effect of anchoring the vertical CFRP strips. Test results were discussed based on shear resistance – mid span deflection, strain in CFRP and maximum crack width of beams. Experimental results reveal that externally CFRP strips can significantly increase the ultimate shear capacity and limit the shear crack width and increase the stiffness of the deep beams with opening.