Correlation of Fine Aggregate Imaging Shape Indices with Asphalt Mixture Performance

TLDR

The study investigates how fine aggregate shape properties affect hot‑mix asphalt performance. The authors quantified aggregate form, angularity, and texture using image‑analysis indices on 22 samples and correlated these metrics with rutting resistance measured by a Purdue wheel‑tracking device under wet and dry conditions. Texture exhibited the strongest positive correlation with rutting resistance, with resistance increasing exponentially as texture increased.

Abstract

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.