Road to success: Queensland trial proves potential of recycled heavy-duty tyres

By Emma Lucey 27 February 2025

A Sunshine Coast trial project has confirmed the successful use of off-the-road (OTR) tyre-derived crumb rubber in bitumen-made roads, leading to more durable, longer-lasting roads.

Recycled rubber from passenger car, bus, and truck tyres has been used in road construction for decades, providing a scientifically tested, safe and environmentally responsible way to dispose of these tyres. For the first time, however, a trial has proven the potential of heavy-duty, OTR tyres for the same application. 

The tyres in question are built to handle the extreme requirements of large machinery and vehicles, such as trucks, bulldozers, tractors, and mining equipment. They are significantly larger and more durable than regular passenger car tyres, and because of their size and design, they are not easy to recycle.    

In Australia, 130,000 tonnes of OTR tyres are discarded each year, with 79 per cent coming from the mining industry and 11 per cent from agriculture, according to Tyre Stewardship Australia. Less than 15 per cent of OTR tyres are recovered across the country, making them a resource that is often wasted. Australia has significant room to improve when it comes to OTR tyre disposal, especially when compared to countries like Denmark (recycling 100 per cent), Canada (87 per cent), and France (78 per cent). These countries have tackled the problem, although the question of what to do with these tyres is still present in many countries around the world.  

Project goal 

OTR tyres are commonly buried 'in-pit' on mining sites, wasting the valuable materials they are made from and posing long-term environmental risks. However, recycling these tyres into useful products, such as crumb rubber for road construction, creates sustainable solutions for industries to reduce their waste and avoid the use of virgin materials in new projects. 

The primary goal of the Sunshine Coast project was to answer questions around the feasibility and benefits of using OTR crumb rubber in road construction. One of the most critical questions: can OTR crumb rubber replace traditional crumb rubber in bitumen blend and asphalt mixes? The materials were tested under real-world conditions to see how they performed in various aspects of road durability and wear. 

Key findings 

One of the most exciting results of the trial was that the modified bitumen, which included OTR crumb rubber, showed greater resistance to aging when exposed to UV radiation. Roads made with this material were more elastic, even after long-term exposure to harsh sunlight and weather. This meant the roads were less likely to crack, increasing their longevity and overall durability compared to roads made with conventional bitumen. 

Another significant outcome was the demonstration of the circular economy model. By sourcing used OTR tyres from a local quarry, processing them through a local business, and using them in council road projects, the Sunshine Coast trial effectively created a closed-loop system. This approach maximised the use of local resources, reduced waste, and cut down on transportation emissions. 

This trial is a prime example of how local councils, industries, and businesses can work together to create sustainable solutions. By turning challenging waste materials into high-value construction materials, the project showed the environmental impacts of such materials can be reduced while also creating economic opportunities for local communities. 

The positive results from this project show that using OTR tyre-derived crumb rubber in road construction is not only feasible but beneficial too. As more councils explore this sustainable option, we could see a future where recycled tyres are widely used to improve road infrastructure across the country. This trial proves that small changes at the local level can lead to a significant impact on reducing waste, creating sustainable jobs, and building better roads for the future.