Effects of steel fibre-aggregate interaction on mechanical behaviour of steel fibre reinforced concrete

This work investigated the effects of fibre type, dosage and maximum aggregate size on the mechanical behaviour of concrete reinforced with steel fibres. Hooked-end steel fibres with 50 and 60 mm length and aspect ratios (length/diameter) of 45, 65 and 80 were used with maximum sizes of coarse aggregate of 10 and 20 mm. The same mix proportions of concrete were used throughout the investigation. Flexural testing of 600 mm square panels was performed. Subsequently, cores were taken from these panels and X-ray computed tomography was used to analyse the positioning of fibres in hardened concrete. The experimental results show that the performance of steel fibre-reinforced concrete improved drastically when compared to plain concrete without fibres. Longer, thinner fibres and smaller aggregates were noted to give the best results.