Shear transfer in CFRP strengthened reinforced concrete

Shear-friction capacity of reinforced concrete strengthened with carbon fibre-reinforced polymer (CFRP) materials was investigated through a series of experiments on initially uncracked push-off specimens. The specimens were designed to fail at a known shear plane in order to isolate the effects of the internal steel and the additional CFRP shear reinforcement. Two internal steel ratios were considered to represent reinforced concrete according to current as well as historic design codes. The effective contributions of externally bonded CFRP composite sheets and those using internal CFRP bars as additional shear reinforcement were studied. The experimental investigation focused on the effects of varying anchorage length as well as various CFRP ratios crossing the shear plane on the ultimate shear capacity of the CFRP strengthened push-off specimens. The experimental results demonstrated a significant increase in shear strength due to the application of CFRP materials as additional shear reinforcement. However, this increase in shear-friction capacity was highly variable and dependent on the strengthening solution used. © 2013, NetComposite Limited