Morphological Study of Coarse Aggregates Using Image Analysis

A newly developed digital image-analysis method was used to characterize the morphological characteristics of coarse aggregates. Regression analyses found that the imaging morphological characteristics of coarse aggregates correlated well with results of other indirect characterization tests such as the test method for index of particle shape and texture (ASTM D 3398); the test method for uncompacted void content of coarse aggregate as influenced by particle shape, surface texture, and grading (modified ASTM C 1252); and the test method for unit weight and voids in aggregate test (ASTM C 29). The imaging morphological characteristics of coarse aggregates also correlated well to the effects of coarse-aggregate properties on hot-mix asphalt concrete mixtures. This research offers a new approach for evaluating coarse-aggregate characteristics of asphalt-concrete mixtures and demonstrates use of an emerging technology for pavement engineering.