South Africa’s first road made from a mixture of recycled tyres and asphalt has been hailed a success, and it may be the start of a new road structure for the country.
In November 2019, the Council for Scientific and Industrial Research (CSIR) in partnership with Much Asphalt, the largest commercial asphalt producer in southern Africa, constructed a 200-metre road in Roodepoort. It is made up of a blend of recycled waste tyre crumbs and a blend of cheap micro fillers, which are inexpensive locally mined products.
The location of the trial section, starting from the weigh bridge of the Much Asphalt Roodepoort branch to the public road tie-in on the approach to the site, was selected specifically to allow ease of continual performance measurement while having up-to-date details on the type and amount of traffic that moves across the section.
The use of waste plastic in road construction is not new. The technology has been used both in Africa and internationally, including Australia, Canada, Ghana, India, Kenya, the Netherlands, New Zealand, Nigeria, the United Kingdom and the United States of America.
However, the South African road construction industry is governed by strict national standards and specifications to ensure the performance of road pavements.
The CSIR has been focusing on locally available alternative additives that would be much cheaper than the conventionally imported additives, as well as creating sustainable use of recycled materials that have an economical benefit for the industry, while resolving an environmental challenge for the country.
Saied Solomons, Sabita CEO says, “Unless we are targeting the specific waste problem that we have in South Africa, there is no other need to use plastic material in our roads. It is also not sensible to use recycled plastic that is already recyclable in plastic. This is the general view of the asphalt road industry, which is also participating in this project.”
To date, the road has no edge breaking and no permanent deformation is present on the surfacing, making it a successful trail run.
Georges Mturi, senior researcher and manager of CSIR’s Advanced Material Testing Laboratories, says the new invention will be promoted into national standards in the construction industry, and he hopes that the road authority will also embrace it in future.
Picture: Facebook / Council for Scientific and Industrial Research