Effects of Compactor Types on Aggregate Orientation of Asphalt Mixtures

Abstract

More than 90% of Malaysian roads are constructed using asphaltic concrete. However, previous investigations of asphaltic concrete have mainly concentrated on the macroscopic properties of the composite materials based on the assumption that the mixtures are homogeneous and isotropic. This paper applies a digital image processing technique to compare the orientations of coarse aggregate particles in asphaltic concrete compacted using Marshall, Servopac and Presbox compactors. The results illustrate that the Servopac compactor produces specimens where the aggregates are more randomlyoriented. However, the Presbox compactor produces specimens that are most randomly oriented at 100% geometrically cubical shape (GCS) aggregate content. Further analysis shows that compaction method has significant effect on aggregate orientation while GCS aggregate content shows otherwise.