An Investigation of the Electrical Conductivity of Different Stone Mastic Asphalt Mixtures

In the recent years, many researches have been carried out on the prevention of icing with electrically conductive asphalt pavements on highways and airports. Although there have been many studies on electrical conductivity in asphalt mixtures, gradation in conductive stone mastic asphalt mixtures has not been studied in details yet. The main purpose of this study is to, for the first time, investigate the effect of aggregate gradation variation on the electrical resistivity and the temperature change of the electrically conductive stone mastic mixtures. In this study, the samples of the conductive stone mastic asphalt (SMA) mixture were produced in three different aggregate gradations (1A, 2A, and 8S) and used with a 5 mm length and 0.2% by weight Carbon Fiber (CF) as conductive component. The Marshall design was performed on the series (1A, 2A, and 8S). The series were made by volume resistivity, temperature changes under constant electrical voltage. Ultrasound transmission velocity was determined by the two-electrode method, and the results were compared. It was concluded that the change in aggregate gradation has a significant effect on the electrical conductivity properties of conductive SMA. The denser the gradation of the stone mastic asphalt mixture, the better the electrical conductivity will be.