eva‎luation of performance and selfhealing behavior in HMAs containing encapsulated sunflower oil

3/9/2023 12:00:00 AM

Selfhealing is an intrinsic behavior in asphalt mixtures which can be boosted by different methods. Encapsulation of rejuvenators is a novel approach to enhance selfhealing performance of asphalt mixtures by means of reducing the viscosity of bitumen and modifying rheological properties of asphalt mixtures. This approach could be used to heal the cracks developed by traffic loading and environmental stresses. The performance and healing behavior of of asphalt mixtures containing synthesized sunflower oil capsules was eva‎luated by different test methods at a variety of performance temperatures in this thesis. To this end dynamic creep, resilient modulus, indirect tensile fatigue and semi-circular bending tests were performed in HMAs containing 0.5, 1 and 2 percents of encapsulated sunflower oil. In order to eva‎luate the healing ability of the asphalt mixtures, 24-hour rest periods were applied on indirect tensile fatigue and semi-circular bending test specimens and different healing indexes were introduced. Besides, varying numbers of freeze-thaw cycles were induced to SCB test specimen to assess the fracture properties of asphalt mixtures containing different amount of encapsulated sunflower oil undergone multiple freeze-thaw damage cycles. The results from different performance tests show almost identical behavior in different mixtures and the results from healing tests show a complete boost in healing ability of mixtures containing encapsulated sunflower oil. The proposed approach in fatigue- healing test indicates that the total accumulated cycles of loading and healing index can be increased up to 23% and 30% respectively by adding 0.5% of sunflower oil capsules to asphalt mixtures. Likewise, the results from semi-circular bending tests at intermediate and low temperatures show that the encapsulated sunflower oil can expand performance life of asphalt mixtures and increase the healing index up to 25% by reducing and healing the damage impacts of freeze-thaw cycles.

كپسول حاوي روغن آفتاب‌گردان , خودترميمي , خستگي , شكست , مخلوط آسفالتي داغ

Encapsulated sunflower oil , Selfhealing , fatigue behavior , Fracture properties , Hot Mix Asphalt

Amirreza Rasoulzadeh Jambor

Mahmood Ameri - Neda Kamboozia