Mix design analysis on steel fiber reinforced concrete

This paper presents a mix design experimental analysis on the steel fiber reinforced concrete. Two types of fiber were analyzed with variations in fiber content and in concrete compressive strength. The main objective, in the first part of the paper, was to obtain correlations between the fiber content and toughness indexes, which could be used as a tool to the fiber proportioning aiming to satisfy the roughness requirements. The exponential model showed the best results for the regression between fiber content and toughness indexes. A mix design methodology, based on these results and other valid rules as Abram's Law, is presented with an example. This methodology was conceived in order to be suitable whatever are the raw materials used, and the toughness and strength requirements. The variation on the compressive strength shows an important interaction with the fiber performance and the toughness indexes, and this must me be taken in account in the steel fiber reinforced concrete mixture proportioning.