Liquid asphalt used in road construction has an updated way to be graded for resistance to: high-temperature rutting, low-temperature cracking, and durability over a range of temperatures and traffic loads thanks to an new standard put out by ASTM International. Labeled D8239, the specification uses the multiple stress creep and recovery test to rate performance levels.

"This standard will be used by pavement materials and design engineers to ensure pavements will last as long as intended," says ASTM International member Bob Kluttz of Kraton Polymers. He adds that contractors, agencies and third-party test laboratories will also use the standard to conduct quality assurance testing. The specification has an equivalent tandard (M332) published by the American Association of State Highway and Transportation Officials.