ABSTRACT
ABSTRACT: It is well documented that performance of asphalt mixture is related to aggregate structure. The Dominant Aggregate Size Range-Interstitial Component (DASR-IC) model provides a framework of gradation-based parameters and associated criteria to link gradation characteristics and volumetric properties to aggregate structure, mixture properties, and field performance. Primary interlocking of coarser aggregate is characterized by DASR parameters, which have been used to establish performance-based criteria based on extensive field rutting data. Studies have also shown that mixtures with acceptable DASR criteria may result in acceptable cracking performance, indicating that IC characteristics strongly influence fracture resistance. Therefore, IC parameters have been used to establish and evaluate preliminary criteria for optimal cracking performance based on limited data. This paper presents the basis and early results for the evaluation and, if necessary, modification of IC criteria, through an extensive laboratory experiment. The challenge was to realistically isolate the effects of the IC, given that all DASR-IC components are interrelated. The results to date indicate that IC parameters have a strong effect on damage rate and fracture energy in a manner consistent with expected trends.
