Wetting Model of Asphalt on the Aggregate Surface and Its Effect Factors

Abstract

Wetting is the process where asphalt infiltrates into the aggregate surface, which is important for the bonding between asphalt and aggregates. In this paper, the aggregate surface textures were simplified to V shape, and a wetting model was established to research the effects of initial temperature and cooling rate of asphalt and aggregate surface texture sizes on the wetting process. The results show that the asphalt infiltrates into the aggregate surface texture faster in the preliminary stage and slower in the later stage. Cooling rate and lower initial temperature of asphalt affect the surface tension and viscosity, resulting in a longer wetting process, but the effects of cooling rate could be ignored in actual practice. The relationship between the infiltration ending time and surface texture size was established, and it is found that the infiltration ending time is essentially proportional to the texture depth squared and inversely proportional to the texture width.