Modulus of asphalt mastics and mixtures incorporating solid waste fillers: micromechanical modelling and experimental evaluation

This study aims to investigate the modulus of asphalt mastics and mixtures with solid waste fillers through integrated micromechanical modelling and experimental investigation. The results indicate that five classical models exhibit lower prediction accuracy for the modulus of asphalt mastic containing solid waste fillers compared to those with mineral fillers, owing to the stronger particle interactions of solid waste fillers. To better account for the stronger particle interactions of solid waste fillers, a modified Ju-Chen model (MJCM) was developed by solving the composite system's radial distribution function. The MJCM demonstrated superior prediction accuracy for the mastic modulus, particularly at high filler concentrations, with an average coefficient of determination of 0.994 at a filler volume fraction of 0.55. Furthermore, by integrating the MJCM with a two-step homogenisation method, a predictive framework was established that accurately correlates the dynamic modulus of asphalt mixtures with their composition across the entire frequency range.