Application of Activated Carbon on Induced Heating-Healing Characteristics of Aged Mixes

Aging phenomenon reduces the flexibility of asphalt pavements. Excessive loading and environmental conditions make asphalt mixes more prone to cracks/micro-cracks initiation and propagation. Cracks/micro-cracks in asphalt mixes can be healed through an induced healing process. Flowing and crack filling capability of asphalt binders play an important role in induced healing efficiency. This paper investigates the effects of different aging level on induced  heating-healing characteristics of asphalt mixes under microwave radiation. Asphalt mixes were modified applying activated carbon to enhance its electromagnetic sensitivity. To compare heating absorption, cubic samples were fabricated at different aging levels. In addition, breaking-healing cycles through indirect tensile (IDT) test was applied to evaluate the effect of aging on induced healing process. Results revealed that microwave heating rate of asphalt mixes decreased as the aging level increased. In addition, aging has adverse effects on induced healing efficiency of asphalt mixes. The experimental testing results indicated that the devastating influence of breaking healing cycles was increased as the aging levels increased, which was more pronounced at higher aging levels.