Influence of Carbon Fibers on the Rutting Susceptibility of Sustainable HMA Mixtures with Untreated Recycled Concrete Aggregates

Abstract

This paper focuses on achieving sustainability to reduce the detrimental effect on the environment and the economic aspects by including several ratios of coarse recycled concrete aggregates (RCA) (25, 50, 75, and 100%) in asphalt mixtures. The methodology included testing all raw materials, the wheel tracking test to assess mechanical performance, and the Marshall design approach to determine the appropriate asphalt content. The outcomes demonstrated no discernible difference between the volumetric characteristics of the asphalt mixtures containing RCA and the control mix. Marshall's stability rose by 14.2% when 50% of the mixture contained RCA compared to the control combination. All combinations containing RCA were performed inferiorly to the control mixture regarding rutting. 19.63% was the greatest increase in rut depth for combinations made entirely of recycled concrete aggregate. Several percentages of 0.2, 0.25, and 0.3% carbon fibers(C. F.) were added to the total weight of the asphalt mixture to enhance rutting per-formance. Marshall's stability and resistance to rutting have significantly increased, attributable to the carbon fibers; nonetheless, the volumetric properties of the asphalt mixture have only slightly altered. The combinations with 0.3% carbon fiber reinforcement and 50% RCA showed the largest gain in Marshall stability, up 34.6% above the control mixture. The same combination had the strongest resistance to rutting, which was —39.08% higher than the control mixture.