Effect of copper slag and reclaimed asphalt pavement on the skid resistance of asphalt mixes

This study describes the findings of an experimental work conducted on asphalt mixtures incorporated with copper slag (CS) and reclaimed asphalt pavement (RAP). CS and RAP are considered waste materials and these waste materials create enormous environmental issues. Their use in the highway construction sector will resolve the landfill problems associated with them. In this study, nine types of asphalt mixtures were prepared with different proportions of CS (0-15%) and RAP (0-30%). These mixes were tested for frictional characteristics under various conditions. The incorporation of CS improved Marshall stability and skid resistance of asphalt pavements. Mix 3 (0%RAP, 15%CS) showed the maximum skid resistance in dry conditions. The increase in skid resistance may be attributed to the high angularity, density, and friction angle of CS particles. However, the incorporation of RAP decreased skid resistance. The CS-RAP mixes also contribute to green technology as waste materials reduce the need for virgin aggregates in the road construction sector. The statistical analysis performed showed that the results are highly significant except in icy conditions where results obtained are insignificant.