CONTRIBUTION OF EXTERNALLY BONDED CFRP TO THE SHEAR CAPACITY OF RC BEAMS

Abstract

Rehabilitation of deteriorated and aged structures with fiber reinforced polymer has been proven as a successful technique due to its outstanding properties such as resistance to corrosion and high stiffness-to-weight ratio. The purpose of this study is to investigate the contribution of the externally bonded carbon fiber reinforced polymer to the shear capacity of the reinforced concrete beams. For this purpose, three reinforced concrete beams strengthened with carbon fiber reinforced polymer in form of side bonded sheet was investigated. The experimental program consisted of three beam specimens that were strengthened with carbon fiber reinforced polymer. One of the beam specimens was not reinforced with transverse steel reinforcement, while the other two were reinforced with stirrups at 200 and 100mm spacing. The strain of the transverse steel reinforcement and the externally bonded CFRP was recorded and compared. In addition, shear capacity predicted by code provisions was compared to the test results. It was indicated that the presence of the transverse steel reinforcement would reduce the contribution of the CFRP to the shear capacity. In addition, the investigated code provisions underestimate the shear capacity of the RC beams strengthened with CFRP

Keywords

• CFRP,Shear strengthening,Shear capacity,FRP,Side bonding

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