The mechanical behaviour of steel fibre reinforced concrete

Abstract

The addition of steel fibres to concrete was first documented in the early 1870′s. In a normal reinforced concrete, the steel reinforcement are straight bars laid in the direction of the tensile force that is applied. In the case of the fibre reinforced concrete, the steel fibres are orientated in a random direction in the concrete matrix. Steel fibre concrete is expected to resist tensile cracking that may occur in mass concrete. This study investigates the flexural strength and the split tensile strength of concrete reinforced with fibres from steel wire rope. The steel fibre used is locally sourced and incorporated in the concrete mix by mass at percentages, 0.5%, 1.0%, 1.5% and 2.0%. A control sample with 0% steel fibre was used as the reference sample. The results show that the incorporation of steel fibre in the concrete matrix, increased the flexural strength across the percentages incorporation while the split tensile strength pattern of increased do not form a trend. The percentage increase/decrease in strength calculated in relation to reference sample at 28 days curing shows that positive effect of steel fibre on concrete is obvious more in improving the flexural strength rather than the split tensile strength. The optimum percentage of 1.5% steel fibre incorporated in concrete is recommended for flexural strength enhancement.