A unified computer-automated system was designed and developed for characterizing the shape of fine and coarse aggregates. The unique features of the system and the experimental design considerations are described. These considerations are related to the required image resolution, field of view, and lighting scheme. The unique features of the system include the ability to analyze fine and coarse aggregates and to quantify texture, angularity, and the three dimensions of form. The developed system is used to measure aggregate shape properties for a wide range of fine and coarse aggregates, and the results are compared with hot-mix asphalt laboratory performance. The analysis shows that the developed procedure yields detailed information on shape properties of aggregates in a short time. The measurements have very good correlation with the resistance of asphalt mixes to permanent deformation measured in the laboratory using different wheel-tracking devices.
Abstract