Finite Element Analysis for the Behavior of Reinforced Concrete T-Section Deep Beams Strengthened with CFRP Sheets

This paper presents a numerical investigation for the behavior of simply supported T-section deep beams, which strengthened with Carbon Fiber Reinforced Polymer (CFRP) sheets. The used specimens were (1.8 m length), (450 mm width and 100 mm depth) flange dimensions, and (180 mm width and 360 mm depth) web dimensions. The specimens were divided into four groups. Mainly, the difference between specimens in each group is in the main reinforcement details. The control group consisted of six beams unstrengthen with CFRP, the other groups were similar to the control group but externally strengthened with CFRP sheets, which were (0.131 mm) thickness. In detail, the second group was strengthened with CFRP sheet at the bottom surface of the web. The third group was strengthened horizontally with CFRP sheets at both sides of the specimen's web. The last group was strengthened with three sheets of CFRP; one at the bottom face of the web and the others at the web sides. The results show that using CFRP at the bottom slightly increased the ultimate strength and changed the failure mode from flexural to shear. Using CFRP at the sides significantly increased both flexural and shear strength, while using CFRP at the sides and bottom of the web did not significantly enhanced the ultimate strength in comparison with using CFRP at the sides only.