Numerical Modelling and Experimental Validation of FRCM-Reinforced Concrete Beams Using Macro-Modelling Techniques

Fibre reinforced cementitious matrix (FRCM) systems are composite materials that are increasingly used for retrofitting masonry and reinforced concrete structures. Their behaviour does not depend only on the mechanical properties of the fibres and the matrix. Therefore, it is essential to perform tensile tests on FRCM coupons, as well as additional tests to investigate whether the interaction between the FRCM system and the substrate can be considered a perfect bond. The aim of this paper is to numerically simulate the behaviour of concrete beams retrofitted with two FRCM composite systems assuming perfect bond. The results of the numerical simulations were compared with experimental data, and it was observed that the adopted models successfully capture the cracking behaviour of both the concrete and the FRCM, as well as overall structural response of the specimens. The main finding was that the behaviour of concrete beams retrofitted with FRCM can be effectively estimated using a macro-modelling approach in numerical simulations. The ultimate load obtained experimentally is between 2% and 20% higher than the numerical value. This is safe and accurate enough for engineering purposes.