Changes of physical properties of asphalt aggregates by heat. A laboratory study

Asphalt mixtures can meet with several different temperatures during their life cycle. The effects of high temperatures on asphalt aggregates have not been examined in detailes yet. Two temperatures were choosen (240 degrees C and 480 degrees C) to be examined. Aggregates meet with 240 degrees C temperature in case of mastix asphalt, and 480 degrees C temperature during asphalt binder analysis. High temperatures cause changes in the physical properties of aggregates that are commonly used in asphalt mixtures. To asses these changes 11/16 mm fractions of three different types (andesite, basalt and dolomite) of Hungarian aggregates were tested in the laboratory by submitting the samples to heating at 240 degrees C and at 480 degrees C. The loss of masses, and particle size distributions coloures and colour differences were recorded and compared. The physical parameters have shown that aggregates behave differently after burning on different temperatures and uniform trends could not be discovered between the type of aggregate, the mechanical properties and thermophysical behaviour of aggregates.