Laboratory Evaluation for Rutting Performance Based on the DASR Porosity of Asphalt Mixture

Abstract

ABSTRACT Researchhas shown that gradation characteristics determine whether the aggregate structure in asphalt mixture results in good performance. A recent study indicated that large enough aggregates should engage dominantly to form an aggregate structure that can resist deformation; also, a new approach identified the porosity of the Dominant Aggregate Size Range (DASR) as the key parameter that determines whether or not a particular gradation results in a suitable aggregate structure. This paper presents a laboratory experiment to evaluate the DASR porosity in terms of its ability to identify unsuitable aggregate structures. Eight dense-graded Superpave mixtures were designed using two aggregate types (limestone and granite). For each aggregate type, mixtures with varying DASR porosity were produced and tested to evaluate laboratory rutting resistance. Test results indicated that the new approach successfully separated mixtures according to their observed laboratory rutting performance, indicating that DASR porosity can serve as an effective parameter to evaluate aggregate structure.