Never mind what some state highway officials say: Asphalt rubber's track record in six states demonstrates it's a proven technology. The time has come that such officials—and politicians who don't want to pay the higher bill—accept that in some circumstances, asphalt rubber is the answer. And that's beyond the fact it's a way to reduce the scrap tire pile.
The material costs roughly $270 per ton, compared with $140 for conventional asphalt. That means it won't always be cost-effective on rural roads that receive little traffic, or in areas without major extremes in temperature.
But in areas where pavement cracking and deterioration is a problem because of heavy traffic, high heat or extreme cold, asphalt rubber seems to do the trick, if state highway engineers in California, Arizona, Florida and elsewhere are to be believed. Asphalt fortified with crumb rubber is particularly effective in preventing reflective cracking—in which a new pavement develops cracks identical to those on the surface underneath—as well as giving a smoother ride and dampening noise.
Asphalt rubber also is proving more versatile than some in the highway community have claimed. Far from being strictly a ``Sun Belt'' phenomenon, the material has proven useful in experimental projects in the high, snowy elevations of Lake Tahoe and the Sierra Nevadas.
Furthermore, while the ``wet process'' technology championed by the Rubber Pavements Association remains the vast favorite, other methods also are proving their worth. Florida uses a different rubber-to-asphalt ratio than the RPA recommends, with excellent results. Highway engineers in Southern California, meanwhile, praise both the generic dry process developed by Barry Takallou and the ``terminal mix'' process from Wright Industries in Texas.
Asphalt rubber isn't ``the solution'' to the scrap tire issue, but it can and should be a contributor to mitigating the problem.