Axial response of fibre reinforced concrete tension members

Abstract

The first sign of tension failure in reinforced concrete is the cracking of the concrete as it reaches its tensile strength. Although the concrete does not carry any tensile load at the crack it does continue to carry load between the cracks. This concrete contribution to the member's stiffness is referred to as tension stiffening. Fibre reinforced concrete is plain concrete with the addition of discontinuous fibres. The addition of steel fibres to the concrete mix allows the concrete to carry some of the load at the cracks. This additional source of strength increases the tension stiffening of the concrete resulting in a tougher member. Several small scale tests were carried out to investigate the behaviour of fibre reinforced concrete. The results show that fibre reinforced concrete exhibits significantly smaller crack widths than plain concrete and as a result more cracks form resulting in reduced crack spacing. Overall, this research project will show that the addition of steel fibres to the concrete mix enhances the performance of concrete.