The adsorption of seven single model species representative of functionalities prevalent in asphalt on siliceous and calcareous aggregates was examined. The seven model species were ranked based on their langmuir monolayer adsorption amounts as well as their adsorption amounts on one or two grams of aggregates. The aggregates used were gravels, limestones, and greywacke. Benzoic acid showed the greatest affinity for the aggregates tested. In addition, the adsorption and desorption behavior of three asphalts with substantially different chemical compositions was determined on a single siliceous aggregate. Differences observed in their behaviors may be attributed to differences in their chemical compositions. The adsorption and water desorption behavior of an ar-4000 asphalt was also determined on threedifferent aggregates: limestone, gravel, and greywacke. Substantialdifferences in the amount adsorbed and desorbed as well as the shapes of their adsorption curves were observed. Limestone adsorbed the most asphalt and retained the largest amount of asphalt after desorption by water. Limestone desorbed the most asphalt in the presence of water, and greywacke desorbed the least. The precoating of antistripping agent on greywacke resulted in less asphalt desorption by water in comparison with coadsorbing antistripping agent with asphalt or with no antistripping agent being present in the system. This paper appears in transportation research record no. 1323, Asphalt mix materials 1991
Abstract