Steel fibre concrete is a composite material where steel fibres are added to the concrete mix to maintain or increase the tensile strength of the concrete after cracking. Steel fibre is used in concrete structures to replace or reduce the traditional reinforcement.

Nowadays, the use of fibre-reinforced concrete has expanded somewhat. In addition to surface floors, reinforced concrete can also be used for:

• in slabs supported on piles,
• slab and strip foundations,
• in between,
• seintes.

The use of fibre-reinforced concrete makes the construction process of floors much faster, as there is no need for the operations associated with the installation of reinforcement. It also ensures that the reinforcement is always in the right place and the risk of reinforcement failure is minimised.

Macropolymeric fibres, also called plastic fibres and synthetic fibres, are an alternative to steel fibres or conventional reinforcement. The CO2 footprint of macrofibres is significantly smaller compared to steel. It is very important to understand the principles of how macrofibres work and how they differ from steel fibre reinforcement. Macropolymer fibres behave somewhat differently compared to steel fibres. We have described this in more detail in the article “Macrofibres vs Steel fibres”.

Applications of macropolymer fibres
Macrofibres are mainly used in soil-supported slabs where stresses are not very high. Another common reason to use macrofibres is an aggressive environment. Macrofibres do not corrode and are more resistant to chemical attack than steel. The third application is in structures where dielectricity is important. The flow conductivity of macrofibres compared to, for example, armour is practically non-existent.