Performance Studies and Future Directions for Mixes Containing RAP and RAS

US Transportation Collection2015PDFTech ReportJensen, DarrinZhou, FujieTexas Transportation InstituteTexas. Dept. of Transportation. Research and Technology Implementation OfficeUnited States. Department of Transportation. Federal Highway AdministrationTexas Transportation InstituteTexasReclaimed asphalt pavementsRecycled materialsResearchShingles0-6738In the last several years, reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) have been widely used in asphalt mixes in Texas. The use of RAP/RAS can significantly reduce the initial cost of asphalt mixtures, conserve energy, and protect our environment. However, there are always two main concerns: variability of RAP/RAS and durability (or cracking) of RAP/RAS mixes. Past studies in Texas have clearly indicated that both RAP and RAS have acceptable variability following the best practices for handling RAP/RAS. This study focused on the durability problems of RAP/RAS asphalt mixes. Specifically, the major objectives of this study were to: 1. Evaluate the impact of RAP/RAS used in hot-mix asphalt and warm-mix asphalt (WMA) on durability/performance problems of the mixes through laboratory evaluation and field survey. 2. Evaluate the impacts of RAP/RAS mixes\u2019 performance and identify approaches for improving the durability problems in terms of mix design. 3. Investigate the cost-benefit ratio of RAP/RAS mixes.97