STUDY OF PHYSICO-CHEMICAL PROPERTIES OF ROAD BITUMEN ORB 70/100

Abstract

The practice of motor roads operation in the Republic of Kazakhstan shows that the durability of asphalt concrete pavements on them is much lower than the standard terms. Therefore, maintaining roads in a condition that meets the requirements of traffic flows is impossible without the use of new, progressive materials and technologies. The main factor influencing a sharp decrease in the service life of road surfaces is the use of low-quality bitumen as a binder in asphalt concrete mixtures, since microcracks develop mainly in its film. In this paper, the physical and mechanical properties of bitumen grade ORB (oil road bitumen) 70/110 of the Atyrau oil refinery were studied. To improve the operational characteristics of bitumen, modification with polyethylene and polystyrene waste was carried out. It is shown that after the addition of modifying additives, the main indicators of bitumen improved. For polyethylene: the depth of needle penetration decreased from 70 to 61 mm, the extensibility decreased by 52 cm, which indicates an improvement in the plasticity and elasticity of bitumen, the softening temperature along the ring and ball increased from 49 to 59 °C, which leads to to reduce the tendency of bitumen to deformation, and the brittleness temperature is within the normal range - not less than -20 °C. In the case of using polystyrene, the penetration characterizing the bitumen hardness decreases from 70 mm to 61 mm; the extensibility increases by 10 cm, which indicates an improvement in the elasticity and strength of bitumen, due to the presence of the resulting structural network. The softening temperature increases, which leads to an improvement in the heat resistance and viscosity of bitumen.