Retreaded tires, tire swings, and even playground flooring are some common uses of recycled tires. And true to the nature of sustainability, tires that were once useless can be repurposed to make durable roads.  

Using a blend of old tires and rubble, a newly developed material has been found to be able to take the pressures of traffic. It’s actually more flexible than standard road materials, and thus less likely to crack. The mix of recycled concrete aggregate (RCA) and tire crumbs is suitable for use as a base layer, beneath the asphalt laid on top. RCA is already used in this way, but the addition of pieces of tire makes it even better able to cope with the elements.

Wasted tires are usually dispatched to landfill sites or incinerated, releasing more CO2 into the air and leading to chemicals leaching into the environment and affecting human health.

An Inventine Mixture

As a solution, an Australian based team of Engineers created a mix of old tire waste along with rubble from construction sites. Ultimately the researchers decided that 0.5 percent fine crumb rubber to 99.5 percent RCA was the sweet spot, maintaining the necessary strength whilst also keeping the two materials cohesive.Too much rubber, and the strength of the material started to decline.

Being tested and proven to have immense strength and flexibility to handle heavy traffic, this all-new construction material will cost less and will be more long lasting in terms of road durability. And the sooner this is put to use, the better, as the study authors note that 1 billion scrap tires are produced annually across the world, while construction, renovation and demolition waste accounts for half of the global waste total each year.

“Traditional road bases are made of unsustainable virgin materials – quarried rock and natural sand,” says civil engineer Mohammad Saberian Boroujeni from RMIT University in Australia. “Our blended material is a 100 percent recycled alternative that offers a new way to reuse tire and building waste, while performing strongly on key criteria like flexibility, strength, and permanent deformation.”

Forward-Looking Sentiments

In addition to becoming a milestone in recycling-related projects, the material is said to be precisely optimum for meeting the road safety standards. Cars will have a better grip on the road built with these waste materials.The researchers say, along with providing benefits of cheaper and greener roads construction, it also enabled us to build roads with fewer cracks in the longer run.

And not only did these engineers find an inventive way to reuse tires, but also wasted rubble materials, essentially tackling “two birds with one stone.” And this is exactly what researcher Boroujeni is saying: “Our blended material is a 100-percent recycled alternative that offers a new way to reuse tires and building waste while performing strongly on key criteria like flexibility, strength, and permanent deformation. As we push towards a circular economy that can eliminate waste and support the continued use of resources, our recycled blend is the right choice for better roads and a better environment.”

Sources: https://www.sciencealert.com/old-tyres-and-rubble-could-make-up-the-sustainable-roads-of-the-future

https://wonderfulengineering.com/researchers-discover-a-way-to-build-durable-roads-by-using-waste-tires/