The University of Melbourne has helped an ambitious manufacturer to develop highly permeable pavements from recycled tyres to improve water supplies and reduce pollution.
Porous Lane has developed its environmentally-friendly pavements in consultation with a range of relevant parties including Councils, urban planners, Tyre Stewardships Australia and Sustainability Victoria.
The first product was trialled at a carpark in South Australia in 2019 and research found the site needed less maintenance than traditional methods while improving cost efficiency, traffic loading and water infiltration.
About three old tyres were used per square metre, to remove more than 1000 tyres from landfill in one project.
A geotechnical engineer from the University, Mahdi Disfani, said the collaboration with industry was key to its success.
“The reason we’ve had so much momentum is because we involved everyone and listened to them,” Disfani said.
“For example, our product was developed in the lab but it has to be laid outside, so we learned a lot about the procedure that councils’ contractors use on site.”
The need for more permeable pavement is to reduce polluted stormwater runoff which can carry microplastics and heavy metals into waterways.
Also, by taking the water away from where it falls, aquifers are insufficiently replenished by rain, reducing the health of trees and plants.
Thirdly, impermeable pavements can increase the risk of flash flooding, damaging property and eroding soils.
Research from the University found that a specific 50/50 ratio of tyre to rock aggregates was best suited to pavement applications.
“With a lot of recycled products, it can be a struggle just to achieve the expected performance,” Disfani said.
“So, when we tested the mixture in the lab under pavement conditions and saw its performance was significantly higher than expected, it was really exciting.”