Effect of different types of fine aggregates on fatigue resistance and self-healing of fine aggregate asphalt matrices

Fatigue cracking is one of the most common types of distress in asphalt pavements. Each asphalt concrete (AC) constituent and its interactions are relevant to characterize the resistance to fatigue cracking of the ACs. Also, for the selection of materials, it is essential to consider not only the capacity of the material resist to fatigue cracking but also its ability to heal. Materials owning self-heal properties can enlarge the ACs fatigue life. Many former studies investigated the self-healing of bituminous materials at the binder level. However, this material property can be dependent on the binder-aggregate interactions. Thus, the current work aims to evaluate the influence of using different fine aggregates on the fatigue cracking resistance and self-healing capacity behavior of fine aggregate matrices (FAMs). First, granite, basalt, and mica schist aggregates were subjected to physical, morphological, and mineralogical characterization. Then, three FAMs were fabricated with the same asphalt binder and these different fine aggregates. To evaluate the fatigue cracking resistance and self-healing capacity of the FAMs, frequency sweep and time sweep tests were conducted. The simplified viscoelastic continuum damage (S-VECD) theory was used to interpret the results of those tests. The mineral composition of the aggregates impacted the stiffness and the fatigue life of the FAMs. However, there was no significant influence of the aggregates on the self-healing capacity of the FAMs, since there was no significant increase in the fatigue life of the materials after the resting periods in the time sweep tests.