Implications of physico-chemical interactions in asphalt mastics on asphalt microstructure

Asphalt binder and filler blend to form asphalt mastic, which constitutes the effective adhesive film in asphalt concrete. Pavement performance can be improved through better engineering of the mastic, which requires a fundamental understanding of the interaction between asphalt and filler. Physico-chemical interactions result in adsorption of polar fractions of the asphalt onto filler surfaces, leading to the formation of an interphase layer on the surface of particles and modifying the asphalt binder matrix. This study seeks to investigate the effects of physico-chemical interaction on binder matrix microstructure using Atomic Force Microscopy (AFM) and qualitatively relate microstructural findings to macroscopic rheology.