Skeleton Filling System Evaluation Method of Asphalt Mixture Based on Compressible Packing Model

Abstract

Asphalt mixtures are composed of skeleton aggregate and filling mortar. Skeleton stability and mortar filling state are of great significance to asphalt mixture performance. First, the aggregate in asphalt mixture is classified into main skeleton aggregate, disruption aggregate, and filling aggregate according to the packing theory and the function of aggregate. The compressive packing model (CPM) is employed to calculate the packing volume and void ratio of multisize aggregates, then the calculation method of the disruption factor and filling factor is proposed and the disruption factor and filling factor of nine kinds of asphalt mixture are calculated. Finally, the main skeleton aggregate distance and mortar area are extracted from the cross section of asphalt mixture through industrial computed tomography (CT) and digital image processing technology. The results demonstrate that the disruption factor exhibits a good correlation with the main skeleton aggregate distance, and the filling factor has a good correlation with the mortar area, which confirms the effectiveness of the disruption and filling factor proposed in this paper.