Experimental study on interfacial tensile bonding performance of pre-heated CFRP-concrete under fast load

Tensile tests of 90 pre-heated CFRP - concrete specimens were conducted under fast load. The influences of three critical parameters on tensile bonding strength were investigated, including loading rate, concrete strength and heating temperature. According to the formula for dynamic tensile strength of concrete suggested by European code CEB-FIP1990 and the formula for the reduced axial tensile strength of concrete after elevated temperature, a model for estimating the interfacial tension bonding strength after elevated temperature was developed and verified. The limit temperature for repair and rehabilitation of concrete component after fire was suggested in terms of different strength grades to concrete. Results show that the tensile bonding strength increases with the increase of loading rate and concrete strength. In the range of 20℃ to 500℃, the interfacial tensile bonding strength significantly decreases with the increasing heating temperature, but no remarkable decrease is observed over 500℃.