Asphalt binders’ property play a crucial role in enhancing the performance and durability of asphalt pavements, making their properties a subject of continual research and development. Asphaltenes, known for its complex molecular structures, have been identified as key components influencing the performance of asphalt binders. This study explored asphaltenes, sourced from Alberta oil sands, as an additive for modifying asphalt binder, utilizing an asphalt binder derived from crude oil. The objective was to evaluate the rutting resistance property of asphalt binders modified with an optimal concentration of 12 % (by weight of binder) asphaltenes. Multiple stress creep recovery (MSCR) test was used to evaluate the rutting resistance property of both unmodified and asphaltenes-modified binders using a dynamic shear rheometer (DSR). The MSCR results demonstrated that asphaltenes-modified binder had reduced non-recoverable creep compliance (𝐽𝑛𝑟). Lower 𝐽𝑛𝑟 values suggest an improved resistance to rutting in the binder post-asphaltenes introduction. The 𝐽𝑛𝑟 values of the asphaltenes-modified binder were consistently below 0.5 kPa-1 which is the requirement for extremely heavy traffic conditions. In addition, the reduction in stress sensitivity after asphaltenes modification highlighted the stabilizing influence of asphaltenes. Hamburg wheel-track (HWT) test was also conducted at an extreme high temperature of 60 °C to investigate the rutting and moisture damage resistance of the mixes before and after asphaltenes modification. A 2.8 times lower rut depth was observed for asphaltenes modified mix with a rutting resistance index (RRI) of 16,457. Additionally, asphaltenes-modified mix did not show any sensitivity to the moisture damage with the absence of stripping inflection point (SIP). These findings underscore the promising potential of asphaltenes in sustainable asphalt binder modification. This study contributes to the ongoing efforts to develop sustainable and high-performance asphalt materials, with the potential to extend the service life of asphalt pavements and minimize maintenance costs.
Keywords: Binder Additive, Asphaltenes, Asphalt Binder Modification, Rutting Resistance, Moisture Sensitivity.
