Tendering fibre reinforced asphalt: what to watch for?

For municipalities, provinces and other clients who want to include fibre reinforced asphalt in a tender, specific points of attention come into play. This article gives a practical checklist.

Why name fibre reinforcement explicitly in a tender?

Without a specific mention, contractors generally opt for the common, best-known solution — often polymer modified bitumen (PMB) or reinforcement mesh. If you want to make use of the advantages of fibre reinforcement (lower production temperature, better recyclability, lower environmental impact), it makes sense to include this as a requirement or award criterion.

Functional specification versus prescribing a fibre type

There are two approaches:

• Functional specification: you set out the desired performance requirements (for example a minimum ITS value, maximum production temperature, minimum service life, MKI score [environmental cost indicator]), and leave the market free to choose the means of achieving this. This fits the trend towards functional specification within tenders and gives room for innovation.

• Prescribing a fibre type: you specifically prescribe a fibre type or dosage. This gives more certainty about the end result, but limits the contractor's freedom and can reduce competition between bidders.

For most tenders, functional specification, supplemented with reference to proven practical results (such as the FIBRA research on the A73), is the most common and flexible approach.

Key points of attention

• Environmental performance substantiation. Ask the bidder to substantiate the environmental performance of the proposed mixture according to the applicable PCR Asphalt guideline and to record it in the National Environmental Database (NMD), so you can objectively compare fibre reinforced mixtures with PMB alternatives.

• Service life substantiation. Ask for substantiation of the expected extension of service life, preferably with reference to independent practical research rather than supplier claims alone.

• Production and processing experience. Ask the bidding asphalt plant to demonstrate that they have experience with homogeneously processing the fibre in question — for example through previous project references.

• Warranty and monitoring. As with other innovative mixtures, include warranty provisions on the service life to be achieved, and consider a monitoring obligation (such as visual inspection and skid resistance measurement) during the warranty period.

• CO₂ Performance Ladder and sustainability award criteria. Fibre reinforcement provides directly usable arguments for sustainability award criteria such as the CO₂ Performance Ladder, thanks to the lower production temperature and reduced reliance on PMB.

Common pitfalls

• Prescribing too tightly without market consultation, so that only one supplier can bid.

• Not paying attention to production experience, which can lead to poorer execution at an asphalt plant without experience in fibre dosing.

• Asking for insufficient substantiation of environmental and service-life claims, so that sustainability benefits cannot be objectively compared between bidders.

In conclusion

Successfully tendering fibre reinforced asphalt mainly requires clear, functionally formulated requirements regarding environmental performance, service life and production experience — with sufficient room for the market to give this shape in its own way.