Numerical Modeling Approach Taking Into Account the Influence of Delamination for Performance Capacity of Reinforced Concrete Beam Strengthened In Bending By CFRP

Reinforced concrete members strengthened in bending by externally bonding of Carbon Fiber Reinforced Polymer ( CFRP) may present several failure modes: failure of material or failure of the interface between concrete-CFRP. Nevertheless, experience gained from testing confirms that in most cases delamination prevails over the other possible rupture modes. Delamination in CFRP strengthened sections is difficult to model because it involves multiple parameters such as FRP stiffness, adhesive material properties, presence of cracks in concrete, among others. A simplified numerical model to predict flexural capacity of reinforced concrete beam strengthened by CFRP at failure is presented in this paper. The experimental validation is presented as well. Based on the result of the proposed model, an equation for the prediction of ultimate flexural capacity to prevent CFRP debonding is proposed.