Experimentally observed behaviour of CFRP sheet strengthening across a shear plane

This paper presents the shear transfer capacity and failure modes of reinforced concrete (RC) push-off specimens strengthened with externally bonded carbon fibre-reinforced polymer (CFRP) sheets. A series of experiments conducted on ten uncracked specimens investigates effectiveness of CFRP as additional shear reinforcement and whether or not the commonly assumed addition of concrete, steel and CFRP shear resistances is appropriate. The key parameters in this investigation considered varying percentages of external CFRP and internal steel reinforcement across the shear plane as well as varying ratio of the bonded area to the force in the CFRP reinforcement. The experimental results demonstrated that the shear strength of the push-off specimens improved due to the application of the CFRP reinforcement and that this enhancement of shear capacity varies in the range of 23% to 84% over the unstrengthened specimens.