Impact of warm-mix asphalt technologies and high reclaimed asphalt pavement content on the performance of alternative asphalt mixtures

Abstract

The use of Warm-mix asphalt (WMA) and reclaimed asphalt pavement (RAP) technologies provide an environmentally-friendly and cost-effective approach to produce new asphalt mixtures. This study's primary objective is to examine the mechanical performance of asphalt mixtures containing RAP using various WMA technologies. In this study, the impact of utilizing 0%, 25%, and 35% RAP contents on the performance of varying WMA mixtures against rutting, fatigue cracking, and moisture damage are evaluated. For this purpose, the rutting performance of the asphalt mixtures and recovered binders were investigated using a loaded wheel tracker (LWT) and multiple stress creep recovery (MSCR), respectively. Further, asphalt mixtures and recovered binders' cracking performance were evaluated using Semi-Circular Bending (SCB) and linear amplitude sweep (LAS) test, respectively. The findings indicated that WMA mixtures containing 35% RAP have an enhanced performance against permanent deformations. Besides, the cracking resistance is improved by incorporating a higher percentage of RAP and WMA technologies. Overall cracking resistance performance of WMA-RAP mixtures is observed to be better compared to HMA-RAP mixtures. Additionally, the LAS test outcomes show that incorporating RAP materials and WMA technologies is associated with improved fatigue life of the WMA-RAP mixtures.