Comparative evaluation for the effect of particles size of reclaimed asphalt pavement (RAP) on the properties of HMA

Abstract

The construction of highway pavement usually consumes a huge amount of aggregate and binder, and at the same time, big quantities of these materials are removed from the old and damaged roads. The disposal of these materials is costing money and effort. The current study aims to investigate the effect of particle size of RAP on the volumetric and mechanical properties of Hot Mix Asphalt (HMA). The study involved replacement of coarse aggregate and fine in wearing layer of the pavement by different percentages up to 40 %. The mechanical tests (Marshall Test and indirect tensile strength test) were conducted to assess the mechanical properties of the obtained mixes. Also, the economical evaluation was conducted to explain the effect of using RAP on the total cost of HMA. The results of the study showed that the replacement of fine aggregate with RAP can be adopted up to 20% of the total aggregate, while the replacement of coarse aggregate is conducted up to 40 % which represents the most coarse aggregate quantity in the mix. Also, the use of RAP in HMA can significantly reduce the cost of obtained HMA compared with that produces with virgin materials.