A New Technique for Constitutive Modeling of SFRC

The application of steel fiber reinforced concrete (SFRC) is continuously increasing; however its potentials are limited due to the lack of universally accepted and reliable design guidelines. The main reason for that is a complex issue of quantifying the tensile stresses, called as residual stresses (σfr), which a cracked section is able to carry due to concrete interaction with fibers. This paper deals with a determination of the stress-crack opening (σfr-w) relation of tensile SFRC. The inverse technique was proposed for determination of σfr employing the experimental data from three-point bending tests on notched beams. Attained residual stress-crack opening relations were compared with the post-cracking behavior, defined using RILEM technique. It was observed, that the inverse technique, proposed by the authors, is an accurate method for determination of the residual stresses of SFRC in tension.