Dielectric model of asphalt pavement materials towards the future electrified road

The dielectric properties of asphalt mixture are crucial for future electrified road (e-road) and pavement non-destructive detection. Few investigations have been conducted on the temperature and frequency influencing the dielectric properties of asphalt pavement materials. The development of e-road requires more accurate prediction models of pavement dielectric properties. To quantify the influence of temperature and frequency on the dielectric properties of asphalt mixtures, the dielectric constants, dielectric loss factor and dielectric loss tangents of aggregate, asphalt binders and asphalt mixtures were tested over the temperature range of -30 to 60°C and frequency range of 200 to 2 000 000 Hz. The results showed that the dielectric constants and dielectric loss factors of aggregate, asphalt binders and asphalt mixtures vary linearly with temperature, while the growth rates vary with the frequency. A model based on nonlinear fitting was first presented to estimate the dielectric loss factor, and another prediction model of the dielectric constant of asphalt mixtures considering the temperature impact was proposed afterwards. Compared with classical models, the average relative error of the proposed model of the dielectric constant is the smallest and is less sensitive to the asphalt mixture. This investigation can cast light on the utilization of non-destructive pavement testing and is potentially valuable for e-road using the electromagnetic properties of asphalt pavement materials. This article is part of the theme issue 'Artificial intelligence in failure analysis of transportation infrastructure and materials'.