Abstract
Bitumen in asphalt concrete undergoes aging under the influence of atmospheric and climatic factors. As a result, the component composition of the bitumen changes, and individual fractions transform into one another. Consequently, the maltenes in the bitumen combine and transform into asphaltenes. An increase in the amount of asphaltenes in bitumen leads to a decrease in elasticity and an increase in brittleness. In this study, the effect of vegetable oil and 5W-30 and 10W-40 motor oils used as agents for restoring the physical and mechanical properties of aged bitumen grades BND 100/130 and BND 70/100 was investigated. The aging process was simulated in a special rotating thin-film furnace for 85 and 225 min. Functional groups in the restoring agents were determined using IR spectroscopy. The effectiveness of the restoring agents was confirmed by determining the physical and mechanical properties of bitumen before and after aging (softening point, needle penetration depth, plasticity, brittleness temperature, ignition temperature in an open crucible). The optimal amount of additives was 3-6 wt.%, and for deeply aged samples, 9-12 wt.%. The results demonstrate the potential of the studied agents for use in the restoration and recycling of road bitumen.