Effect of aggregate type on the fatigue durability of asphalt mixtures

Abstract

The effect of aggregate type on the fatigue behaviour of asphalt mixtures is an important variable for ensuring greater durability of pavements over time. This study presents the main results of an assessment of the effect of the physical properties of different aggregates on the fatigue behaviour of asphalt mixtures. Two fatigue tests were used for this study, one standardized and another developed recently which evaluates dissipated energy during the cracking of asphalt mixtures (EBADE® test). Three types of aggregates were used and adjusted to a semi-dense aggregate gradation: two of fluvial type (AF1 and AF2) and one from a quarry (AC). Two different shredding processes were used to obtain the aggregates. The results obtained show that there is a strong relationship between the shape and texture of the fine aggregates and the fatigue behaviour of the mixtures. It was also showed that the greater the thickness of the mixture in the pavement structure, the more influence these properties have. Likewise, the shape and texture of the fine aggregate influence the ability of asphalt mixtures to dissipate energy during fatigue damage.