Comparative cracking resistance‐cost study for the hot mix asphalt (HMA) mixtures made of natural and recycled asphaltic materials

Abstract

Cracking performance of control and RAPed hot mix asphalt (HMA) mixtures was studied under low and medium temperatures. The effects of recycled asphalt pavement (RAP) content (0 and 50%), compaction method, and temperature (−20, 0 and +20°C) on KIf and KIIf were investigated. Cracking resistances of both modes showed similar trends. The fracture toughness of RAPed mixture at +20°C was higher than the control mixture. However, at −20°C, KIf and KIIf obtained from the RAPed mixture were about 22% lower than control mixture. A cost analysis was performed to compare the manufacturing costs of both mixtures. Accordingly, the cost of HMA mixture containing 50% RAP was 26% less than the control mixture. The proposed life‐cost index in the RAPed mixture was 10, 25, and 100% greater than the control mixture at −20, 0, and +20°C, respectively. Temperature and RAP content had the most important impacts on fracture toughness and cost, respectively.