ASPHALT-CONCRETE MIX PREPARATION PROCESS Russian patent published in 2002 - IPC

FIELD: manufacture of road-building materials. SUBSTANCE: bitumen is combined with mineral materials, treated by modifying composition consisting of ethylene/polypropylene rubber and polypropylene or polyethylene at weight ratio from 98:2 to 50:50, in the form of 1.5- 5.0-mm granules in amounts 1.5 to 5.0% of the weight of bitumen. The latter can be preliminarily supplemented by 0.5- 1.0 wt parts of cationic surfactant or its mixture with product of polymerization of unsaturated hydrocarbon C5-C9 fractions per 100 wt parts of bitumen. EFFECT: improved crack resistance and waterproofness and increased longevity of asphalt-concrete. 2 cl, 1 tbl, 5 ex