Rutting performance of asphalt mixtures containing treated RCA and reinforced by carbon fibers

Abstract

This study examined the rutting performance of hot asphalt mixtures containing treated RCA and reinforced by carbon fibers. The methodology involved substituting RCA instead of coarse virgin aggregates in the several percentages (20, 40, 60, 80, and 100%) that were treated by being submerged for 24 hours in an acetic acid solution with a concentration of 0.1M. Carbon fibers were added in several percentages of 0.15, 0.25, and 0.35% by the entire weight of the mix to produce cylindrical specimens (4×2.5 inches) for evaluating the Marshall and volumetric properties, and rectangular slabs (30×40×5 cm) for evaluating rutting resistance. The study finds, that incorporating RCA and carbon fibers did not substantially affect the volumetric characteristics of asphalt mixtures, but Marshall's stability increased. The combination containing 60% RCA and 0.35% carbon fibers showed the greatest increase in Marshall stability, which was 35.81% over the control mixture. The addition of RCA led to a reduction in the rutting performance, whereas the addition of carbon fibers increased it, as seen by a decrease in rutting depth. The combination incorporating 40% RCA and 0.35% carbon fibers exhibited a minimum rutting depth of 40.64% lower than the control mixture. The combination incorporating 20% RCA and 0.35% carbon fibers exhibited the maximum level of dynamic stability, which was 1.64 times greater than the control mixture.