Relationship of Adhesion Performance between Asphalt Binder Using Solvent Elution Method and Crushed Pebbles Asphalt Mixture

Abstract

Abundant crushed pebbles are used as substitutes for high-quality aggregate to solve the shortage of asphalt pavement aggregate in Tibet. However, since crushed pebbles belong to acid aggregates with a smooth surface, the adhesion between them and asphalt binder and its improvement measures need further study. Thus, the solvent elution method was used to verify the adhesion between the asphalt binder and various aggregates, and the microscopic changes of the eluted asphalt binder were analyzed by Fourier transform infrared (FTIR) and gel permeation chromatography (GPC). The results show that the freeze-thaw splitting strength ratios of various asphalt mixtures with crushed pebbles were all above 80%. The addition of mineral powder enhanced the absorption from resins and asphaltenes in the aggregate’s surface. Also, the joint action of cement and antistripping agent improved the absorption capacity of aggregates to molecules. Furthermore, there was a significant correlation (r>0.5) between the weight average molecular weight and performance indexes of asphalt mixture, indicating that the solvent elution method has certain guiding significance for the study of adhesion between the asphalt binder and aggregate.