Many factors, such as traffic, drainage, structure and climatic variations, impact the field performance of asphalt concrete. However, asphalt concrete performance has been more accurately predicted when laboratory material properties are known, so ASTM International Committee D04 on Road and Paving Materials has approved a new standard, ASTM D7460, Test Method for Determining Fatigue Failure of Compacted Asphalt Concrete Subjected to Repeated Flexural Bending. Under the jurisdiction of Subcommittee D04.26 on Fundamental/Mechanistic Tests, ASTM D7460 will include  information that can be used to judge the variation of fatigue testing results and will provide testing laboratories with a better method for determining the test failure point than has been previously available.

Richard W. May, consultant and D04 member, says that the new standard is the best and most appropriate material testing approach for estimating the longitudinal fatigue cracking performance of an asphalt concrete mixture, subjected to the tensile strain levels experienced in a specific pavement cross-section.

May notes that interested parties are invited to contribute to future revisions of ASTM D7460, as well as to participate in future round robin testing that will be needed to develop an estimate of multilaboratory precision.
              
For technical information, contact Richard W. May, consultant, Wichita, Kan. (phone: 316-841-7501; rmay25@cox.net). Committee D04 meets Dec. 9-11 during the December committee week in Miami Beach, Fla. For meeting or membership information, contact Daniel Smith (phone: 610-832-9727; dsmith@astm.org).

Release #8062/Sept08