Old Tires into New Roads: Save Cost and Cut Noise

Engineers are designing quieter streets by adding rubber “crumbs”, reclaimed from shredded tires, to the bitumen and crushed stone used to make asphalt.

Enough tires are recycled in America each year to produce 20,000 lane-miles of road pavement mix, enough to re-pave about 0.5% of America's roads, according to Liberty Tire Recycling, a Pittsburgh firm that handles around a third of America's recycled tires.(1)

It is now possible to make rubberized asphalt less expensively than the traditional sort because rubber can partially replace bitumen, the binding agent used to hold the crushed stones together in ordinary asphalt. Bitumen is derived from oil, which means its price has risen over the past decade alongside that of crude oil. (1)

Discarded tires are cheap and are likely to get cheaper. In rich countries, around one tire is thrown away per person per year. (1)

In Hawaii we burn tires at the AES coal plant. This is much better than dumping them in a landfill or wasting fuel to send them out of state. But we should be making new roads with them.

(1) The Economist, When the rubber hits the road, June 2012.