For over 20 years, binding agents for road construction have increasingly been modified with new polymers. These can be sustainably replaced by rubber powder made from recycled old tyres, which is perfect for modifying road construction bitumen and asphalt in accordance with E GmBA. Adding five to ten per cent recycled rubber powder to the binder improves road quality, lowers maintenance costs and helps to reduce road noise.
Asphalt consists of approx. 95 % of aggregate and 5 % of binder, usually bitumen, the thick, black residual product from petroleum refining, which is characterised by its high viscosity. The binder bonds the stone material and gives the road its characteristic black colour.
Proven technology for the sustainable optimisation of road quality
The addition of recycled rubber powder (normally less than 1 mm) sustainably improves the quality of roads. Rutting is prevented, as is cracking due to climatic influences. The rubber modification of asphalt and bitumen extends the temperature window within which roads are elastic and therefore resistant to the effects of heat and cold.
Rubber-modified asphalt also pays off economically
This results in significantly lower maintenance costs and roads need to be closed less frequently for maintenance work. The additional costs for the asphalt modification are more than offset by the savings in maintenance.
In addition, rubber-modified asphalt enables the production of porous asphalt mixtures that are particularly suitable for reducing road noise. All EU member states now have action plans to prevent traffic noise, in which porous asphalt is an important instrument.
For test purposes, Kurz Karkassenhandel equipped its premises with rubber-modified asphalt in 2020, which is subjected to high levels of stress from the manoeuvring and shearing movements of heavy container vehicles. "After almost nine months in use," says Hanna Schöberl, Managing Director of Kurz Karkassenhandel, "the asphalt still looks like new. We don't see any signs of wear or ruts and will only use the open-pored rubber asphalt in future."
The use of recycled rubber powder from used tyres as a substitute for mostly imported virgin polymers also makes an important contribution to achieving the goals of the Green Deal, helps to reduce CO2 emissions and makes the EU less dependent on imports of scarce raw materials. Rubber asphalt made from used tyres is a forward-looking solution, especially as it can even be recycled itself.
