HILTON HEAD ISLAND, S.C—Barriers still exist to the expanded use of rubber-modified asphalt, despite the proven benefits of the technology, according to a speaker at the 32nd Clemson University Global Tire Industry Conference.
“One of the best ways to deal with scrap tires is to put them back into the road,” said Richard Gust, president, national accounts for Liberty Tire Recycling.
The idea of modifying asphalt with scrap rubber was advanced in Europe as early as 1938, and in 1949 an asphalt-rubber mix was used on an experimental stretch of road in Akron, according to Gust.
The commercial application of rubber-modified asphalt began in Arizona in the mid-1960s, and since then the technology has more than proven itself, he said.
Rubber-modified asphalt is safer and more durable than conventional asphalt, reduces both noise and costs, and is environmentally responsible and sustainable, according to Gust.
Nevertheless, many state highway departments are still leery of rubberized asphalt, and the reasons are somewhat complicated, he said.
In the 1960s and for years afterward, Gust said, rubberized asphalt technology was covered by a patent, which effectively prevented its expansion from Arizona. But even after the patents lapsed, major problems arose.