Adhesion of Asphalt to Natural Aggregates and Sanitary Ceramic Waste

Materials (Basel). 2025 Mar 7;18(6):1201. doi: 10.3390/ma18061201.

Abstract

Research was conducted to improve our knowledge pertaining to the physical processes happening at the interfaces between solids (i.e., asphalt and aggregate) and to determine the appropriate choice of asphalt as well as additives to enhance the longevity of bituminous and mineral mixtures. The lowest mean contact angle CA with asphalt at 140 °C was obtained for dolomite and asphalt 50/70 + W (45.0°) and was 29.5% lower than the highest obtained for granodiorite and asphalt 45/80-55 (63.8°). The lowest SFE value was obtained for dolomite aggregate, it was 14.3% lower than the highest value and amounted to 47.68 mJ/m2. In the case of waste ceramic aggregate, the lowest mean asphalt detachment stress (0.77 MPa) was obtained using 45/80-55 modified asphalt without adhesives, at 120 °C, and it was 69.2% lower than the highest value (2.50 MPa) obtained when using samples with 45/80-55 + W modified asphalt at 160 °C. Statistically, the temperatures of both the asphalt and aggregate had the most considerable influence on the asphalt-to-aggregate adhesion, as measured by the contact angle of the aggregate with the asphalt, as well as the pull-off. The employed aggregate, as defined by its roughness characteristics, was also of importance, but to a lesser degree. The type of asphalt had the smallest impact on adhesion, but it is crucial to remember that the viscosity of asphalt is strongly influenced by temperature.

Keywords: adhesion; asphalt; roughness; sanitary ceramic waste aggregate; surface free energy.