Prediction of Post-Cracking Behaviour in SFRC Elements Under in-Plane Stresses

In recent years, the use of steel fibre reinforced concrete (SFRC) has increasingly spread in several engineering fields. However, the use of this composite material requires an adjustment of the computational tools normally adopted in current design, as well as a review of the implemented constitutive relationships, which are usually referred to ordinary plain or reinforced concrete. In this paper, this problem has been tackled by means of a numerical procedure, based on nonlinear fracture mechanics concepts, which allows to correctly simulate the fibre contribution, especially in the post-cracking stage. More in detail, a macroscopic model (named 2D-PARC), already developed for ordinary RC structures, has been extended to SFRC elements subjected to plane stresses, by taking into account realistic semi-empirical constitutive laws for concrete, steel fibres and ordinary reinforcement. The effectiveness of the proposed approach has been verified through comparisons with significant experimental full-scale tests available in technical literature concerning SFRC beams, with or without traditional reinforcement.