NEW ROADS WITH END-OF-LIFE TYRES

Using end-of-life tyres in roads is not new, it has been tried and tested since the 1960s and proven to increase performance and durability. What is new is the 422 asphalt specification, tested on roads in Bendigo, Victoria – which improves performance at a cheaper price.

In Australia, 450,000t of tyres reach their end of life each year, yet only 14 per cent of these materials are recovered and used locally. Some of which are recovered into roads, providing increased performance qualities, creating longer road pavement life and reducing maintenance compared to neat bitumen roads.

The higher road performance is owing to the rubber from used tyres in the bitumen, creating a stiffer binder with elastic characteristics. Roads built with rubber crack less, have improved skid resistance, less road rutting, perform better in high temperatures and have reduced shape loss.

Looking for ways to reduce road construction costs, while still getting the performance benefits of rubber in roads, Tyre Stewardship Australia (TSA), Boral, the City of Bendigo and the Department of Transport Victoria (DoTV) have partnered to test the new, and more cost-effective, 422 asphalt specification.

Boral’s National Technology Manager, Ryan Jansz, said, “The use of crumb rubber has been part of asphalt road specifications in Victoria, and even internationally, for many years.

“But what is unique about the new 422 asphalt specification is that it allows a more affordable product to be developed for local councils and road owners with modest budgets, while still achieving a performance benefit often exceeding that of originally intended treatment.”

Boral has produced two mixes of the new 422 asphalt specification, tested on roads of Heyington Place, Kooyong Close and Sunrise Courts in the City of Bendigo in early 2021.

One year on, inspections have confirmed the demonstration roads are performing well.

Lina Goodman, CEO of Tyre Stewardship Australia, said, “It’s just another reason local councils across Australia should get on board. Getting the valuable resources out of used tyres and creating better-performing roads is now more affordable too.”

Now with the new, cheaper 422 asphalt specification, using crumb rubber in roads is more accessible for councils.

It is also recovering the materials from an end-of-life product and turning it into a new value-added solution, delivering circular economy principles.

“We are seeing an emerging movement of local councils using tyre-derived material in their roads and infrastructure, and by doing so, saving on greenhouse gas emissions. Why wouldn’t every council jump on board?,” Ms Goodman said.

TSA is working with local councils, connecting them to the various uses of crumb rubber already being utilised across the country.

Email an expert at TSA about harnessing the benefits of using crumb rubber in road and infrastructure projects: getonboard@tyrestewardshipaustralia.org.au