In the scientific community, the possibilities of using plastic in road construction have also been studied for some time. German road construction expert Prof. Johannes Beckedahl, who worked for a long time at the University of Wuppertal, thinks it's basically good to think about "upcycling" plastic waste, but is skeptical about prefabricated solutions like those used by VolkerWessels. He doubts that a durable road construction is possible with modules. The modules would have to be laid on the base in such a way that the same storage conditions exist everywhere. Otherwise, each module or precast element would settle unevenly under use. With the consequence of possible fractures or step formations. Beckedahl, on the other hand, takes a more positive view of processing plastic waste into granules. "A correctly produced asphalt modified with plastic granulate or rubber granulate, for example from used tires, and its high-quality paving can be an advantageous and service life-extending alternative to conventional asphalts," says the expert. However, he said, the prerequisite is always that the formulation for a modified asphalt mixture is determined and tested in the laboratory so that the mixture is optimized for the intended use. The environmental compatibility of roads with modified asphalt could be problematic, Beckedahl finds. Abrasion on roads with plastic content, for example, could release microplastics.
Roads made of or with recycled plastic waste nevertheless have the potential in principle to make a significant contribution to sustainability. They can help to conserve resources in terms of materials and land on a large scale - and that all over the world, because there are roads everywhere and plastic waste is a resource everywhere. However, it is not yet possible to predict the extent to which this type of construction will become established and which type will then prove to be the best.