ABSTRACT
The use of economical and environment-friendly recycled asphalt materials is now popular for asphalt pavement construction. Reclaimed Asphalt Pavement (RAP) and Recycled Asphalt Shingles (RAS) are used in Hot-Mix Asphalt (HMA). However, as higher amounts of RAP/RAS material are being promoted, the potential for premature pavement distresses especially cracking is increasing. In this research, four Recycled Superpave mixtures (SR) with varying RAP and RAS contents have been evaluated. Two of these mixtures contained 10% RAP and 5% RAS, while the other two contained 25% RAP but no RAS. Illinois semicircular bending and Florida indirect tension tests were performed to assess mixture cracking and fracture behavior. The test results show that mixtures containing 10% RAP and 5% RAS have relatively low fracture energy and flexibility index but higher resilient modulus. However, creep compliance and energy ratio of these mixtures are lower. Mixtures containing 10% RAP and 5% RAS are also stiffer, more prone to cracking, and they tend to absorb less fracture energy. Mixtures with 25% RAP and without any RAS showed the opposite behavior.
