Durability Studies on Fly Ash Stabilized Reclaimed Asphalt Pavement Materials

Reclaimed asphalt pavement (RAP) has predominantly been on the global research focus because of its cost effectiveness as well as sustainability. Lack of proper design guidelines being main reasons, a limited amount of research findings are put into practice. In addition, age hardening of the asphalt coating present over the RAP, affects its long term performance. To confidently use the RAP in flexible pavements, it is essential to evaluate the durability and long term performance of RAP mixes besides for their strength and stiffness properties. The current study aims at evaluating the durability and long term performance of the selected RAP-VA mixes with alkali activated fly ash as a stabilizer. The mixes were selected based on the target unconfined compressive strengths (UCS) specified by the Indian Roads Congress (IRC) guidelines. The RAP-VA mixes were subjected to alternate wet-dry cycles and the weight loss after 12 cycles was measured. The weight loss is found to be within the permissible limits of 14% by weight. Retained UC strength after 12 cycles, for each mix, were also evaluated to know the effect of moisture variation on the strength and was observed that the strength loss was very minimal