Laboratory Investigation and Numerical Modelling Effect of Carbon Nanotubes on Hot Mix Asphalt Permanent Displacement

One of the primary causes of asphalt pavement deterioration is rutting; in contrast, one of the most effective methods to address this type of damage is the use of additives and quality evaluation during the design stages. In this research, laboratory testing and modeling using Abaqus software were employed to validate the laboratory results and predict and assess the potential for rutting. Carbon nanotubes (CNTs) were selected as an additive due to their exceptional mechanical properties and molecular interactions with bitumen. These nanotubes were used to modify the bitumen for the preparation of laboratory samples. The laboratory results from the Marshall quotient, resilient modulus test indicated that the addition of CNTs enhances the mixture’s resistance to permanent deformation, even at elevated temperatures. Based on the results of the laboratory tests, the samples produced with bitumen modified using 0.5% CNT exhibited the best overall performance. Furthermore, modeling simulations using Abaqus software corroborated these findings, showing that carbon nanotubes reduce rut depth and improve load distribution within the pavement structure. The results of the economic analysis also indicate that the use of nanocarbon in asphalt is economically cost-effective and sustainable.