Description
Asphaltenes are major constituents of asphalt binders that are insoluble in alkanes. However, till date, very limited research studies have made use of asphaltene as an indicator to investigate the aging properties of asphalt-rubber (AR) binders and mixtures. The main objective of this study was to analyze the effect of short-term and long-term aging properties on asphalt binders and mixtures with asphaltene proportion as a performance indicator. The novel approach taken in this study was first of its kind since it synergized asphalt binder fundamental properties and aging performance criteria with the asphalt mixture performance analyses. Experimental investigation in this study encompassed evaluation of virgin VG-30 and crumb rubber modified CRMB-60 asphalt binders, and corresponding dense-graded asphalt mixtures prepared with these binders at short- and long-term aging conditions. A total of 498 test data points were accrued during the binder and E* dynamic modulus test mixture testing program for further analyses. Based on the asphaltene extraction and E* dynamic modulus tests on asphalt binders and mixtures respectively, it was concluded that rubber-modified binder is definitely a better performing material. It is envisioned that this study will definitely help understand and analyze aging behavior of asphalt binders and mixtures from rational perspective. Additionally, with the inclusion of E* as a mixture performance assessor, this study will certainly find a place to be an integral part of flexible pavement design guidelines focusing on long-term aging performance criterion.
