ABSTRACT
To investigate the effect of fines on the aging of bitumen, a set of fourteen different mastics was prepared and aged with a modified Rolling Thin Film Oven Test. The unmodified paving grade bitumen of 70/100 penetration was used. The bitumen was extracted both from the unaged and aged mastic and analyzed with Dynamic Shear Rheometer and Fourier Transform Infrared (FT-IR). The fines were analyzed for the Loss on ignition, as well as by the FT-IR. The extracted bitumen was found to be softer than the original one in some of the blends, implying rejuvenation. However, based on aggregate analysis, the precipitation of bitumen into the aggregate fines during extraction was noticed. Conversely, for some bitumen specimens, the FT-IR spectra revealed the presence of fines, which in many cases convoluted the area of sulfoxides peak. The rejuvenation observed by rheological testing was the effect of extraction artifacts rather than deoxidation.
