Properties of reclaimed asphalt pavement with Bio-Heating Oil as a rejuvenator considering ageing

This paper studies the use of Bio Heating Oil (BHO), a waste derived from biodiesel production, as the rejuvenator of aged bitumen of reclaimed asphalt pavement (RAP). The BHO was added to the blend during the asphalt concrete mixing process (dry process). The study assessed whether BHO is suitable to rejuvenate a high percentage of RAP (60 % or 80 %) to produce hot- and warm-mix asphalt concrete adequate for medium/low-traffic roads. The analysis involved the laboratory evaluation of volumetric and Marshall properties and the assessment of mechanical performance. The study also evaluated workability in a gyratory compactor, rutting resistance using wheel tracking tests, and resistance to water damage by indirect tensile strength testing. Because durability after long-term ageing may be an issue for the studied mixtures, the laboratory testing program assessed stiffness and resistance to fatigue cracking in four-point bending tests performed before and after applying a pre-validated ageing protocol to the specimens. The study also evaluated slabs' texture depth and skid resistance with and without ageing. The findings confirm that hot-mix and warm-mix asphalt concrete with 60 % and 80 % RAP, respectively, and 10 % of BHO by mass of bitumen fulfil the requirements for use in medium/low-traffic roadways regarding water sensitivity, stiffness, resistance to permanent deformation and fatigue, and surface performance, even after long-term ageing.