2/21/02

Jim Killian, 334/844-2509

AU TRANSPORTATION PEAK PROMINENT IN ASPHALT PERFORMANCE TESTING

AUBURN -- Last Sunday's high-profile NASCAR race at Daytona International Speedway featured celebrity drivers whizzing around the famed high-banked oval at nearly 200 mph, running flat-out for 500 miles.

But it was just another routine day hundreds of miles away in East Alabama, where drivers of 152,000-pound trucks plodded along at 45 mph on a 1.7-mile oval test track, putting in their usual 16-hour, thousand-mile day.

This less glamorous track, where vehicles run six days a week, week-in, week-out, is operated by the National Center for Asphalt Technology, a research center in Auburn University's Samuel Ginn College of Engineering.

"Our goal has been the safety, comfort and longevity of our asphalt highways," NCAT director Ray Brown says. "The NCAT test track represents one of the few efforts in the history of highway research to duplicate the real-life wear and tear on asphalt roadways in a scientific manner that yields real data."

The center's ultimate goal is to save municipal, state and federal government agencies billions in tax dollars as the result of better-built asphalt roads. Alabama alone has more than 11,000 miles of roads paved in asphalt.

At the same time, the track is also testing tires, lubricants and components such as axles, as well as comparing such items as manual and automatic transmissions and new technologies that may be introduced into future cars and trucks.

Trucks began rolling down the track near AU in September, 2000, and will continue through November in the first cycle of testing. Each truck pulls three trailers that are loaded to a calibrated weight of 20,000 pounds per axle.

As they move around the track, the trucks pull their loads over 46 different types of asphalt surfaces, each 200 feet long and representing testing surfaces from nine states that range from Florida in the South to Oklahoma and Indiana in the West and in the Midwest. The Federal Highway Administration is also a participant in the research.

"All of the surfaces are doing reasonably well," Brown says. "They represent a wide range of asphalt mixes, all laid down to the specifications of the host states, under the supervision of their officials, and with the actual materials they use, which was trucked in."

Brown says early data indicates that modified asphalt mixes that include polymers can significantly reduce damage to asphalt highways, particularly in terms of rutting - the name given to the cross-sectional depression that follow tire tracking along some highways.

The cost of adding such polymers is about 15 percent more than normal asphalt mixes, Brown says. Currently, such mixes are used where traffic counts determine that they would be useful.

Additional data indicates that porous asphalt may be safer and quieter than other, non-porous surfaces, Brown adds, noting that the more open surfaces act in a manner similar to acoustical tile in ceilings to keep dampen noise levels.

"Some states are spending millions of dollars putting up noise abatement walls where interstate corridors run through cities," Brown says. "There is a large savings potential here, as well as an opportunity to control the esthetics of these corridors in a more pleasing manner."

These porous asphalt mixes also allow water to drain through the surface layer, reducing wheel splash and increasing visibility as a result.

Brown said he looks forward to the transportation conference that NCAT will host at Auburn in November to report results from the first round of testing to track sponsors, academicians, and research scientists and engineers.

"We're confident that we can telescope some 15 years of actual road use into this two-year testing cycle and come up with data that will lead to better, safer, longer-lasting highways," he added.

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CONTACT: Brown, 334/844-6244.

(Click here for more information on AU's Peaks of Excellence program in transportation.)