Predicting the dielectric properties based on micromechanical modeling for asphalt mastics

Investigating the dielectric properties of asphalt mastics is crucial for understanding the overall dielectric responses of asphalt mixtures. Analyses of the test results for asphalt mastics and evaluation of the existing models reveal that the classical models are inadequate for predicting the dielectric properties of asphalt mastics. This shortcoming is considered to originate from the inability of these models to account for the physical and chemical interactions that occur at the material interface. Therefore, in this study, a particle polarization mechanism with an electrically independent interface is explored, which takes into account the interface of composites and the size effect is intrinsically inherited. A micromechanical model for multi-phase matrix–particle composites that includes the interface effect is developed based on the proposed particle polarization theory, allowing calculation of the effective dielectric constant for multi-phase composites over a wide range of particle sizes. Compared with the overprediction of the classical models, the proposed model yields smaller predicted results that better match the actual measurement results. This is because the proposed model takes into account the influence of the interface effect on the overall dielectric responses of the asphalt mastic, and the interface effect weakens the polarization of the entire asphalt mastic.