Efficient asphalt recycling in Switzerland

September 2023

Switzerland is built, at least as far as the road network is concerned. Therefore, despite recycling, significantly more asphalt is produced today than can be reinstalled in new roads. Empa researcher Martins Zaumanis has set himself the goal of increasing the recycled content of asphalt - with adapted production methods and simple instructions. Two test sections with recycled asphalt in Uster and on the Lukmanier Pass are promising.

In Switzerland, the growing amount of old asphalt in landfills is a problem that is now being addressed through innovative research. The “HighRAP” project, led by Martins Zaumanis and in collaboration with authorities and industry partners, aims to maximise the use of recycled asphalt in road construction.

Challenges and solutions
Waste asphalt is a challenging resource. Its binder, bitumen, ages and stiffens over time, making it difficult to use. In addition, old asphalt is often a mixture of different road layers and time periods, which affects its homogeneity. Zaumanis’ research project offers solutions here. Specialised testing methods and a newly developed computational model make it easier to reuse old asphalt.

Practical tests and applications
The project has already proven its practicality in two pilot projects. In Uster, it was possible to incorporate up to 50% recycled asphalt into the road surface without sacrificing performance. Even on the climatically challenging Lukmanier Pass, asphalt with high recycled content was successfully used. These results encourage the expanded use of recycled materials.

Forward-looking research
The project not only offers practical solutions for road construction, but also sheds new light on the possibilities of using recycled material efficiently and sustainably. Martins Zaumanis is confident that his research will help to significantly reduce the amount of used asphalt in landfills.

With the “HighRAP” project, sustainable road construction in Switzerland is taking off. New methods, political will and successful practical tests make a future with less waste and more recycling in road construction seem realistic.

More articles