Technical-economic studies about the effect of Nano-carbon black on asphalt mixtures

Abstract

Nanomaterial have been considered one of the new additives by researchers for use in asphalt pavement. In this study, first, mechanical properties such as marshall stability and marshall flow as well as vol-umetric properties of asphalt mixture such as voids in the total mix (VTM), voids in the mineral aggregate (VMA), and voids filled with asphalt (VFA) were investigated. Then, the rutting resistance of the asphalt mix-ture, which is a measure of resistance to permanent deformation, was evaluated. Finally, economic analysis of the effect of different percentages of Nano-carbon black on a 1 km long road was evaluated. The results showed that adding Nano carbon black to the asphalt mixture in low percentages reduced the marshall stability due to the lack of proper bonding between bitumen and Nano carbon black. By increasing the amount of Nano carbon black in the asphalt mixture, marshall stability increased. Also, Nano carbon black has clearly shown potential for improving the permanent deformation resistance of the modified asphalt mixture. During the Marshall Quo-tient (MQ) test, more than two times increase in rutting resistance was observed by adding more than 10% Nano carbon black to the asphalt mixture. On the other hand, the results of the economic analysis showed that the addition of 15, 17.5, 13, and 20% of Nano carbon black, respectively, has made the project economical. Due to the positive effect of adding Nano carbon black on the mechanical properties of asphalt mixtures, it is rec-ommended to use Nano carbon black extensively in areas where the pavement suffers from a lack of load-bearing capacity.