Influence of binary waste mixtures on road performance of asphalt and asphalt mixture.

The utilization of processed waste materials in road construction is of utmost significance from the environmental and economic viewpoints. In this paper, waste cooking oil (WCO) and ground tire rubber (GTR) were applied to modify the asphalt binder. Based on the optimal content of both modifiers, sixteen asphalt samples with different combinations of the two wastes were designed. Relevant tests including basic properties along with rheological behavior and chemical characterization were carried out on the modified asphalt. The results indicated that the modified asphalt with 20 wt % GTR and 2.5 wt %-5 wt. % WCO exhibited satisfactory high temperature resistance and low temperature rheological properties. The Fourier transform infrared spectroscopic investigation revealed that the presence of GTR increased the concentration of styrene and butadiene while the addition of WCO introduced fatty acids and esters to modified asphalt. Overall, the road performance studies demonstrate that modified asphalt mixture with 5 wt % WCO and 20 wt % GTR displayed a markedly improved anti-rutting properties, water stability and superior low-temperature performance compared to normal asphalt mixture. • The molecular structures of WTO/GTR-modified asphalt were analyzed. • Asphalt modified with an appropriate amount of GTR and WCO exhibited optimum properties. • GTR increased the concentration of functional groups in modified asphalt binder. • WCO introduced fatty acids and esters to modified asphalt binder. • WTO/GTR-modified asphalt mixtures showed a promising application in road industry. [ABSTRACT FROM AUTHOR]