Experimental study on the bondline behavior between concrete and FRP materials

This paper aims to investigate the debonding mechanism of fibre reinforced polymer (FRP) materials externally applied to the concrete substrate. An experimental program has been performed on the unidirectional carbon fibre reinforced polymer (CFRP) laminates adhered to the concrete prisms in order to address some of the factors expected to affect the interfacial bond behaviour using single lap shear test. Although many researchers have investigated the bondline behaviour between FRP and concrete using single lap shear test set-up, the dependency of bond on the initial unbonded zone has not been studied. In this study, several experiments have been conducted to monitor the effects of the unbonded zone on the single lap shear test results. The results of maximum load versus slip and also shear stress distribution along FRP for each group of samples obtained by means of pre-installed strain gauges on the FRP are presented