PERFORMANCE-BASED SEAL COAT ASPHALT SPECIFICATIONS. INTERIM REPORT

The Texas Department of Transportation is moving to adopt the requirements and nomenclature of the asphalt binders developed for the Strategic Highway Research Program's (SHRP's) Superpave design system for hot-mixed asphalt concrete. Under the present specifications, this would require the Department to maintain, test, and support two separate specifications for basically the same material, since the SHRP study did not include asphalt binders used for seal coats. This study successfully determined that the asphalts presently being used in Texas can meet the PG, or Superpave, grading system. The findings were based on official samples of material being used in the Department's program, though additional work must be undertaken to determine that these materials are being matched with the locations (environmentally as well as physically) to yield the most satisfactory product.