Literature Review for Long Term Research on Bituminous Coarse Aggregate (0-1707-1)

The Soils and Aggregates Branch of the Construction Division of the Texas Department of Transportation (TxDOT) has the primary responsibility for overseeing aggregate quality issues. An overall process review of selected testing and monitoring protocols used within the branch is needed to ensure that the needs of TxDOT and the state of Texas are continuously met. Two key areas are addressed in this review: (1) a review and upgrade of the Aggregate Quality Monitoring Program (AQMP) and (2) a review and upgrade of the proposed Surface Aggregate Classification System. The assessment of the AQMP includes evaluation of other tests that might be required as replacements and/or supplements for the tests currently used to monitor quality. The study also includes an assessment of the frequency and protocol of testing and suggests changes where necessary. The Surface Aggregate Classification System evaluation will involve defining the best tests and protocols to ensure excellent wet weather skid properties (level 1) and to ensure excellent overall hot-mix quality (level 2) for a safe and durable hot-mix surface. The project also includes a long-term field-monitoring program to ensure that selected tests and protocols correlate with field experience.