Performance evaluations of HMA containing reclaimed asphalt pavement and reclaimed asphalt shingles

The use of recycled materials in the form of Reclaimed Asphalt Pavement (RAP) and Reclaimed Asphalt Shingles (RAS) in Hot Mix Asphalt (HMA) has become regular practice; however, when compared to the supply of these materials their use is still conservative. Comparative studies on the performance effects are needed to propose guidelines for the handling, processing, and incorporation of RAS and high RAP into mix design procedures. Presented here are results of examining lab produced HMA containing RAS and RAP. The RAS study indicates no significant difference in the stiffness in RAS vs. RAP mixes across most temperatures, and that similar cold temperature performances can be expected. The high RAP study indicates that while RAP content affects HMA stiffness, aggregate and virgin binder selections may also have an effect on the amount that RAP content will impact the properties of a mix.