Development of Restoring Rubber Additives for Aged Road Bitumen

Modern ideas about the aging process of road binders and the principles of restoring their properties and structure are given. Technology of production of standard restored road binders (bitumen and polymer modified bituminous materials) using devulcanized rubber crumb (RC) obtained by crushing spent tires, elemental sulfur, oil dispersing agents (asphalt from deasphalting tar and heavy gas oil catalytic cracking) and polymer-thermoplastic elastomer is proposed. In addition, this technology provides the skillful use of elemental sulfur, waste asphalt from the process of deasphalting tars, and straight-run tar that is in surplus at many refineries. The physical and chemical properties of the restored road binders were evaluated for compliance with the Russian and American standards.