Towards an Experimental Protocol for the Study of Induction Heating in Asphalt Mastics

The development of asphalt mixtures with improved electrical and thermal properties is crucial in terms of producing suitable mixtures for the induction heating without losing their durability. The main scope of this research is to evaluate experimentally the impact of filler-sized electrically conductive additives on the induction heating efficiency and the rheological performance of asphalt mixtures. Within this framework, an experimental assessment protocol of structural and non-structural important parameters of induction heated asphalt mastics – asphalt mixtures without stone aggregates and sand – was developed. It was observed that by adding iron powder as filler-sized conductive additive to asphalt mastics the electrical and thermal properties improve. Moreover, the rheological investigations of different conductive asphalt mastics show the importance of adding iron powder after replacing the amount of mineral filler in order to maintain the workability of mastics. The micro-morphological observation of asphalt mastics using scanning electron microscopy illustrates the impact of filler-size particles – minerals and conductive additives – on the skeleton of asphalt mastics.