Research into compaction homogeneity of asphalt concrete by applying image analysis

Abstract

A compacted bituminous mixture is commonly regarded as an isotropic material when considering both mechanical and structural properties. The work covers structural examinations of bitumen mixtures focused on assessment of an inherent anisotropy of a viscoelastic composite material. The results of compaction homogeneity examinations of the asphalt mixture of an asphaltic concrete type are presented herein. The examined samples were taken from a road pavement in parallel and perpendicular directions to the road surface. Particles orientation of a mineral aggregate skeleton and homogeneity of their distribution were examined. On the basis of performed examinations it was concluded that the asphalt mixture of an asphaltic concrete type shows certain inherent anisotropy of structure. It has been shown that together with an increase in size of coarse particles their amount in asphaltic concrete diminishes and heterogeneity of their distribution in a structure of mixture increases.