Abstract
The actual problem of the oil refining industry is to improve the process of oxidation of heavy oil residues and the properties of oil bitumen. One way to solve the problem is to add modifiers. The addition of modifiers leads to an intensification of the oxidation process and an increase in the characteristics of the bituminous binders. The work aims to study the effect of adding rubber crumb on the process of vacuum residue oxidation and the properties of the obtained rubber-bitumen binders (RBB). The influence of the size of crumb rubber and its content, the mixing stage and oxidation modes on the properties of rubber-bitumen binders are determined. Vacuum residue from the Omsk oil refinery was used as a raw material, which was modified with crumb rubber with a dispersion of 0.6‒1.0 mm and less than 0.6 mm. The novelty of the research is the addition of crumb rubber to the vacuum residue and the oxidation process to obtain bitumen. The product of vacuum residue oxidation for 2 h at 260 °С with preliminary mixing of 2 wt.% crumb rubber with particle sizes less than 0.6 mm at 180 °С and additional mixing of 8 wt.% crumb rubber after oxidation corresponds to the brand of rubber-bitumen binder RBB 60/90. The rubber-bitumen binder is characterized by high elasticity and low Fraas point. Рrepared аsphalt concrete mixture based on RBB corresponded to type B according to physical and mechanical parameters. The complex shear modulus of the samples decreases with the temperature increase. Short-term aging resulted in increased shear modulus for all samples.