Cohesive zone approach to the cyclic response of cracked concrete beams reinforced with externally bonded FRP plate.

AbstractTo predict the cyclic response of concrete strengthened with FRP, this paper presents a new analytical solution, which uses the cohesive zone model (CZM). Based on the CZM, for intermediate crack-induced debonding, with intermediate flexural cracking of concrete beams repaired with FRP plate, the deteriorative effect of cyclic loading on the adhesive joints (interface) is investigated. To accomplish this aim, a cyclic damage process is coupled with a CZM to predict the cumulative damage evolution along the FRP-to-concrete interface as a function of the number of cycles. Comparing the results from the present model with those found in the literature shows that the constitutive model is able to accurately predict the overall cyclic loading response of concrete strengthened with FRP composites. The main advantage of the proposed model is that it gives the variation of the mid-span deflection, damage development, and interfacial stress distribution with increasing load cycles, and number of loading cycles. We conclude that cyclic degradation of the component materials significantly reduces the resistance and lifespan of the repaired structures. [ABSTRACT FROM AUTHOR]