Cost-Effective Use of Reclaimed Asphalt Mixtures with Various Rubber Modification Technologies for Pavement Maintenance Applications

Abstract

The use of sustainable materials in road construction has been gaining popularity to provide a better future for the next generations. This study investigates the possible use of two common sustainable road construction materials, recycled asphalt pavement (RAP) and recycled tire rubber (RTR), for pavement maintenance applications. Mixtures were produced either with combined RAP and RTRs or 100% RAP with petroleum-based (RAP-A) and bio-based (RAP-B) rejuvenating oils. Because pavement maintenance applications such as pothole patching have traditionally been performed with cold mixtures (CM), a typical cold patching mixture was also investigated along with six hot asphalt mixtures. RTR mixtures were produced using different rubber modification technologies. They were manufactured using crumb rubber wet (WET), crumb rubber dry (DRY), devulcanized rubber (DEV), and crumb rubber terminal blend (TB) technologies. Each RTR-modified mixture included 40% RAP and approximately 12% rubber content by weight of the binder. The performance of the mixtures was compared using dynamic modus (DM) testing for linear viscoelastic characterization, flow number (FN) testing for rutting potential, and tensile strength ratio (TSR) testing for moisture susceptibility. The cost-effectiveness of different mixtures was performed using the life cycle cost analyses (LCCA) approach for bituminous materials. The results showed that any recycled hot-mix asphalt outperformed the CM. The 100% hot RAP mixture with petroleum-based rejuvenator performed as well as any combined RTR-RAP mixtures, and it became the most cost-effective alternative for pavement maintenance applications.