Fracture Behaviour of Steel Fibre Reinforced Rubcrete

Abstract

Discussions on the failures in quasi-brittle materials like concrete provide a better understanding of its response to loadings when it is presented with the backdrop of fracture mechanics. Rubcrete is a term used to denote a concrete in which mineral aggregates are replaced by crumb rubber. An idea about the energy utilised to open the unit area of a crack surface can be obtained by using Fracture Energy (Gf). Results of experimental investigations on M40 grade concrete with steel fibres and crumb rubber to determine the Gf as per RILEM TC50 FMC is presented in this paper. The rubcrete variants considered in this paper include M40 grade concrete in which fine aggregates are replaced by 5, 10, 15 and 20% with crumb rubber. The steel fibre reinforced concrete variants have steel fibre proportions of 0.25, 0.5, 0.75 and 1% of the total volume of the mix. Steel fibre reinforced rubcrete mixes have a rubber content of 15%. It can be concluded that, with the addition of steel fibres of about 1% by the total volume of the mix, the Gf increases by 51% and 84% for the ordinary concrete and the rubcrete specimen, respectively.