Correlation of Fine Aggregate Imaging Shape Indices with Asphalt Mixture Performance

This study addresses the relationship between fine aggregate shape properties and the performance of hot-mix asphalt. Aggregate shape was expressed as three independent properties: form, angularity, and texture. Image analysis procedures and indices were developed to capture these properties. The indices were measured for 22 aggregate samples. The samples were related to the hot-mix asphalt rutting resistance measured under wet and dry conditions in the Purdue wheel-tracking device. Among the different aggregate shape properties, texture had the strongest correlation with rutting resistance. Resistance to rutting increased exponentially with an increase in aggregate texture.