Steel fibre reinforced concrete began in the late 19th century, and among the first application was the patching of bomb craters in runways during World War II.

Today, steel fibres are frequently utilised to reinforce concrete in replacement of traditional steel fabric reinforcement, where it is intended for control of early thermal contraction and shrinkage cracking.

Concrete is a brittle material, and whilst strong in compression, it is particularly weak when subject to tensile stresses created when external loads are exerted. Fibres can be added to concrete on a conveyor, which allows homogenous dispersal throughout the mix, creating 3-dimensional reinforcement. Individually providing anchorage in the concrete, steel wire fibres can enhance this brittle matrix, giving a ductile material with a high load-carrying capacity.

There are two mechanisms of steel fibre concrete. Firstly, as the fibres are randomly distributed in the mix, they intercept early age micro-cracks, inhibiting their tendency to form into larger cracks. The fibres bridging these cracks will provide considerable residual load-carrying capacity, allowing a possible reduction in slab thickness and creating improved concrete crack-control properties.

This enhanced ductility is governed by 'Re,3' values of steel fibre performance in flexure, determined from a 3rd-point simply supported beam test. As fibre dosages increase so do these values, indicating greater concrete toughness. As well as material cost savings due to slab thickness reduction, by replacing traditional steel fabric reinforcement with steel fibres, an economic solution can be achieved further by a reduction in set-up time.

Using a suitable fibre at high dosages, enhanced crack-distribution characteristics can be utilised to allow large area (up to 2,500m²) 'jointless' panels to be cast, reducing the need for potentially troublesome induced stress relieving joints.

Further technical benefits include increased abrasion, impact and fatigue resistance, as well as greater protection of weak areas of the slab, such as the joint arris.

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