Long-term skid resistance of asphalt surfacings and aggregates’ mineralogical composition: Generalisation to pavements made of different aggregate types

Abstract

The work presented in this paper aims to find the relationship between the types of coarse aggregates used in asphalt mixes and the long-term skid resistance capacity of the resulting pavements. It builds on previous work which proposed a relationship between the mineralogical composition of aggregates and the skid resistance of asphalt surfacings in the long-term. Here, the focus of the inquiry is shifted from an asphalt surface of one type of aggregate to a mix of several types of aggregates. Polishing tests and friction measurements were performed in the laboratory on different pavement samples, followed by a mineralogical analysis of the coarse aggregates of these samples to define a new parameter termed “Averaged Aggregate Hardness Parameter”. The results found that this parameter correlates well with the long-term skid resistance. Finally for practical use, the paper proposes analytical formulas to link the new pavement hardness parameter with the long-term skid resistance of pavements.