PRODUCTION OF THERMOSTABLE ROAD BITUMENS BY THE METHOD OF "OXIDATION-COMPOUNDING"

The paper proposes a technology for producing petroleum road bitumen by compounding deeply oxidized bitumen with tar, pre-oxidized to various temperatures, in order to produce binders stable to the processes of thermo-oxidative aging. The rate of technological and chemical aging of tar and bitumen has been studied. It was found that tar is most susceptible to technological, and bitumen to chemical aging. It is shown that the use of tar pre-oxidation technology is a promising direction in bitumen production in the production of standard grades of bitumen binders. The obtained compounded bitumens have high extensibility values at 250C and maximum tensile force, which characterizes their high cohesive properties, as well as high values of the needle penetration depth at 00C and low brittleness temperatures, which indicate good low-temperature properties of bitumen. It has been revealed that the use of oxidized tar with a softening point of 360C during compounding with deeply oxidized bitumen can achieve the minimum values of softening temperature change after aging and obtain standard bitumen grades BND 70/100 and BND 100/130 according to GOST 33133-2014. The resulting compounded bitumen is less susceptible to destructive and thermo-oxidative aging processes and can be effectively used for paving