NUMERICAL METHODOLOGY FOR THE PREDICTION OF THE LOCAL BOND-SLIP LAW FOR CONCRETE ELEMENTS STRENGTHENED WITH FRP

The characterization of an accurate local bond-slip model is one of the fundamental challenges in modelling fibre reinforced polymer (FRP) strengthened reinforced concrete (RC). This paper presents a novel method for developing and validating an accurate bond-slip model. It utilizes a numerical procedure based on the finite difference method and incorporates a metaheuristic optimization algorithm, so that no specific bond-slip law shape is needed. The presented methodology also enables modelling tests with premature failure before reaching the maximum load. The obtained results confirm the accuracy of the methodology. Due to space limitations, only results related to NSM specimens are presented.