PREDICTION OF CRACK-INDUCED DEBONDING FAILURE IN R/C STRUCTURES FLEXURALLY STRENGTHENED WITH EXTERNALLY BONDED FRP COMPOSITES

Abstract

Crack-induced debonding failures are observed to be very dominant and sometimes unpreventable in concrete members strengthened with externally bonded FRP composites. Many research efforts have been concentrated on developing the debonding predictive models and different models have already appeared in some design guides and codes. However, most models are either lacking of comprehensive under-standing of failure mechanisms (empirical models) or too complex for use in practice. As a complement to our preliminary proposal which has been adopted and included in the current JSCE guideline, this pa-per presents a theoretically reasonable and analytically feasible methodology on how to predict the debonding failure induced from intermediate flexural cracks in FRP strengthened R/C beams. The predictions based on the present analytical model are compared to 180 experimental data collected from existing literature and a close agreement has been obtained.