Mechanical properties of cold mixed asphalt

Abstract

The mechanical and performance characteristics of cold mix asphalt derived from straight-run bitumen blended with dissolved polythene were assessed to determine the engineering, environmental, and economic feasibility of a re- cently developed product for pavement maintenance. The cold mix asphalt binder was created by treating a portion of straight-run bitumen with chemically dissolved polythene waste sachets at a temperature of approximately 80°C, employing an alkaline emulsifier, chemical surfactant, and water. The formulation for the cold mix asphalt involved 35% coarse aggregates, 65% fine aggregate, and 10% mineral filler, with an optimal binder content of 8.3%. Standard laboratory Marshall tests, static loading/unloading in both laboratory and field settings, and real-time traffic loads were applied to the cold asphalt mixes to establish comparative performance. The Marshall Stability, flow, and density of the experimental cold mix asphalt were determined as 5.08 kN, 4.0 mm, and 1.98 g/cm3, respectively. In compari- son, the corresponding values for the other three commercially available cold asphalt mixes ranged from 0 to 4.27 kN, 0 to 5.5 mm, and 1.60 to 1.85 g/cm3. The rate of deformation of experimental cold mix with respect to time and traffic load respectively 0.0086mm/week and 0.00877mm/standard 80 kN standard axle, which are more favorable than the corresponding values for the commercial mixes.