Estimation of bonding quality between bitumen and aggregate under asphalt mixture manufacturing condition by thermal contact resistance measurement

Asphalt pavements are obtained after mixing aggregates and bitumen both preheated in a temperature range between 100 °C and 160 °C. The manufacturing temperatures are important to ensure good bitumen and aggregates bonding. However, the accurate evaluation of the bonding quality remains a challenge. A setup has been used to quantify the bonding quality between hot bitumen and granular substrate.The method is based on the determination of the thermal contact resistance (TCR) when hot bitumen is putted into contact with granular substrate. This TCR is assessed from solving inverse heat conduction problem and is interpreted as a bonding quality indicator. Results prove that the increase of component temperatures induces better bonding between bitumen and the substrate.