Evaluation of fatigue damage and healing of asphalt mastics for different filler contents

Fatigue damage and healing are two very important characteristics for designing asphalt concrete (AC). Fatigue damage degrades material properties, whereas healing recovers the material properties at rest periods after damage. Mastic is a blend of asphalt binder and fine aggregates (fillers) and is a component of AC composite. Fatigue damage and healing mostly occur in the asphalt binder and mastic. This study evaluates the effect of the fines and binder grade of mastic on the fatigue damage and healing of mastic. A total of six mastics (with different binder grade and asphalt-filler ratio) are tested to determine fatigue damage and healing. It is found that fatigue resistance increases up to the addition of 20% fines in the mastic. Addition of fines more than 20% decreases the fatigue resistance. A physicochemical model is used to predict healing in mastic. Healing decreases with the addition of fines in the binder and higher binder grade.