EVALUATION OF PERCENTAGE FRACTURE AND GRADATION ON BEHAVIOR OF ASPHALT CONCRETE AND AGGREGATE BASE. EXECUTIVE SUMMARY

The results are reported of a study designed to develop a sound approach to the utilization of crushed aggregates in highway and airfield pavements, and provide a rational link between highway and airfield pavement designs and their utilization of crushed aggregates. The study consisted of two tasks. The first consisted of a literature review of current specifications used in Alaska and the Pacific Northwest followed by reviews of the literature pertaining to the effect of aggregate fracture and gradation on the behavior of both aggregate base and asphalt concrete materials. The second task consisted of a laboratory plan to evaluate the effect of aggregate fracture and gradation on the properties of aggregate base and asphalt concrete. The details are described of each of these tasks and the results are presented. The computer study used to analyze the results is also described. Recommendations are presented which are based on the study results and concern changes to the current design and specification procedures for the utilization of crushed aggregates.