Experimental and Theoretical Investigation on Shear Strengthening of RC Precraced Continuous T-beams Using CFRP Strips

Carbon fiber reinforced polymer (CFRP) sheets are externally bonded to reinforced concrete (RC) members to provide additional strength such as flexural and shear strength. It has been widely accepted that carbon fiber reinforced polymers (CFRPs) can be used effectively to strengthen reinforced concrete (RC) members. This paper is intended to study and use externally bonded CFRP strips to repair and strengthen RC continuous T-beams, as well as investigating the influence of material (CFRP) on repair of shear defect on RC continuous T-beams. This defect will be repaired using different CFRP strips under sustained loading. Total of three RC continuous T-beams with identical sizes of 150x320x3650 mm, flange width of 400 mm and flange thickness of 120 mm were used, and the orientation involved 0/90 degree and 45/135 degree in 3 sides wrap schemes. All beams were tested under sustained loading. Tests result showed the effectiveness and shear capacity of the CFRP strengthened specimens. The shear enhancement of the CFRP strengthened beams varied between 26.57% and 38.56% over the control beam. This study confirms that the CFRP strip technique significantly enhances the shear capacity of reinforced concrete shear beams.