Steel fibres or synthetic macro fibres? How to choose the right reinforcement
Both replace traditional mesh reinforcement — but when do you choose steel and when synthetic? A comparison on performance, cost, handling and CO₂.
Anyone looking to realise a concrete floor or pavement without traditional mesh reinforcement soon arrives at fibre reinforcement. The two dominant flavours: high-tensile steel fibres and structural synthetic macro fibres. Both are CE-certified under EN 14889 and both replace reinforcing steel — but the trade-off differs per project.
When steel fibres?
Steel fibres such as our MPZG HT+ series deliver the highest flexural tensile strength and ductility per kilo. For heavily loaded structures — tunnels, foundations, floors with high point loads — they are often the logical choice. At 10–35 kg/m³, the dosage is higher than for synthetic fibres, but the price per kilo is considerably lower.
Do watch the boundary conditions: steel fibres can become visible at the surface and are susceptible to corrosion in aggressive environments.
When synthetic macro fibres?
Synthetic macro fibres such as TwistR® are gaining ground in floors, cycle paths and yard pavements. At 2–6 kg/m³ the dosage is low, the fibres do not corrode, and the CO₂ footprint is up to 98% lower than with traditional steel reinforcement. On projects such as the NDSM shipyard and the cycle path in Wijckel, the business case has by now been amply proven: up to 46% lower costs.
In acid- or alkali-exposed environments (agricultural floors, greenhouses), a polyolefin fibre such as the Wiking 4050 TR is even the only durable option.
In practice: run the numbers
The right choice follows from the design and the costs. With our savings calculator you compare the cost of traditional steel reinforcement with TwistR® fibre reinforcement for your specific project in a minute. For bespoke advice, our technical advisers are on hand.