A new research project from Tyre Stewardship Australia (TSA) and RMIT University will evaluate the performance of crumb rubber in asphalt made from old car tyres.
The project, co-funded by TSA, RMIT and the Victorian Department of Transport, will evaluate to what extent and in what proportion – when mixed with truck tyres, for instance – passenger car tyres can be recycled in road asphalt pavements.
RMIT University’s Filippo Giustozzi said the project would look to address barriers to the increased consumption of recycled Australian passenger tyres in the growing road sector for crumb rubber.
“Currently, most crumb rubber asphalt and sealing use recycled tyres from trucks almost exclusively. That’s because truck tyres have a higher content of natural rubber, thus better chemical compatibility with bitumen,” he said.
Giustozzi added that most recycling infrastructure in Australia is currently set up to process truck tyres into crumb and granule because the market for passenger tyres is so small.
“Through this research project, we want to objectively ascertain whether there are any performance differences between passenger and truck tyres in asphalt road applications,” he said.
“We will use passenger car tyres – or a combination of truck and passenger tyres – to produce crumb rubber mixes with five to 20 per cent rubber.”
According to TSA CEO Lina Goodman, Australia generates the equivalent of 56 million used car tyres every year. Around 30 per cent of those end up in landfill or are stockpiled, with 85 per cent recovered and exported.
“This evidence-based research will allow the road industry to respond to the increasing push of the Australian Government for recycling more while ‘exporting’ less,” Goodman said.
“Through partnerships like this research project with RMIT and Department of Transport, TSA is constantly looking to find innovative and sustainable ways to push towards a circular economy that can eliminate waste and support the continual use of resources, including the best recycled blends for better roads and a better environment.”
The research project is believed to be the first of its kind testing crumb rubber from passenger car tyres in bitumen and asphalt in Australia.
The study, which begins this week, will run bitumen lab testing until July 2021, with asphalt testing completed a year later.