Climate-neutral and circular by 2030: the role of fibres

Rijkswaterstaat has a clear ambition: to build, manage and maintain fully climate-neutral and circular by 2030, using 50% less primary raw material. This target is being pursued along two tracks: extending service life while retaining the value of existing assets, and developing new climate-neutral and circular materials. Fibre reinforcement of asphalt and concrete touches on both tracks at once. In this article we show how.

Two routes to the same goal

Within its Climate-Neutral and Circular programme, Rijkswaterstaat works along four tracks: technology, governance, contracting and financing. For the construction site and construction logistics of building, management and maintenance projects, the aim is a 100% CO₂ reduction and an 80% NOx reduction, partly through the switch from fossil-fuelled to non-fossil-fuelled equipment.

For fibre reinforced mixtures, the first track — service life extension — is particularly relevant. The longer a road surface or concrete structure lasts without maintenance, the less often new primary raw materials are needed. This is precisely where fibre reinforcement proves its value.

Service life extension: the core of the business case

Research into fibre reinforced asphalt (the European FIBRA project, carried out with, among others, Rijkswaterstaat and BAM) showed that manufacturers of commercial fibres claim a service life extension of the road surface of at least 50%, with an extension of the service life of the asphalt layer itself of up to 200%, depending on fibre type and application. Less maintenance means less milling, less transport of new material and less traffic disruption — factors that all feed directly into the CO₂ footprint of a project.

The same logic applies to fibre reinforced concrete. By limiting crack formation and increasing flexural tensile strength, a structure stays intact for longer without steel corroding or concrete needing to be replaced.

Fewer primary raw materials through fibres instead of PMB

A second route runs via material choice. Traditionally, asphalt has been reinforced with polymer-modified bitumen (PMB) or with reinforcement mesh. PMB, however, is harder to recycle than standard penetration bitumen, and reinforcement mesh requires a separate work step with additional material and machinery. Aramid fibres added to standard penetration bitumen offer an alternative: the asphalt becomes stronger, remains readily recyclable, and no separate layer or work step is needed.

Gains can also be made in terms of energy consumption. Fibre reinforced mixtures with penetration bitumen can be produced at a lower temperature than mixtures with PMB — around 20°C lower in practical tests on the A73. A lower production temperature means less energy consumption at the asphalt plant and less emission of substances harmful to workers' health during application.

A practical calculation example: CO₂ savings through fibre reinforcement

In a recent project — the foundation for tree and flower planters — traditional steel reinforcement was replaced with fibre reinforcement. The result: a net saving of 1,500 kg of reinforcement steel, equivalent to a CO₂ reduction of 98% compared with the original steel solution. The entire design could be converted to fibre reinforcement within two days, including approval from the local council.

This kind of calculation example is exactly what clients need in order to factor fibre reinforcement into their own CO₂ Performance Ladder and tender criteria. Where steel has a relatively high production footprint (extraction, smelting, transport), the production of synthetic fibres is considerably less burdensome per kilogram of reinforcement capacity delivered.

Emission-free construction: making the combination

Fibre reinforcement becomes even more powerful in combination with emission-free equipment on the construction site. In a recent project for a temporary construction road, a base and binder asphalt layer with aramid fibre reinforcement was laid emission-free — a concrete step towards the RWS ambition for climate-neutral construction logistics. The combination of a longer service life (less future equipment needed) and emission-free construction (less emission now) reinforces itself.

What does this mean for your project?

For municipalities, provinces and contractors working towards the RWS 2030 target, fibre reinforcement is one of the most readily available instruments:

• No waiting for new technology: fibre reinforcement can already be deployed with existing production and processing equipment.

• Measurable CO₂ gains: both through material savings (less steel, less PMB) and through lower production temperatures.

• Alignment with existing standards: the results are well substantiated within the CO₂ Performance Ladder and the new PCR Asfalt 2026 for environmental performance calculations.

In conclusion

Rijkswaterstaat's ambition to work climate-neutral and circular by 2030, using 50% less primary raw material, is a substantial challenge. Fibre reinforcement of asphalt and concrete offers a concrete, directly applicable contribution: longer service life, less steel and PMB, lower production temperatures and measurable CO₂ reduction per project.

• Dutch Fiber Trading, project case studies (dftrading.eu/projecten)