Investigating of the Effects of Nanomaterials on the Moisture Susceptibility of Asphalt Mixtures Containing Glass Cullets

The pavement industry is one of the industries that has considered using waste to partially replace the aggregates in asphalt mixtures. Despite its many environmental and technical benefits, the use of crushed glass increases the moisture damage potential of asphalt mixtures. Therefore, in the present study, the aim was to investigate the effects of two nano antistripping additives called nano iron oxide (Fe2O3) and nano aluminum oxide (Al2O3) on the moisture susceptibility of hot mix asphalt (HMA) mixtures containing crushed glass. The glass asphalt mixtures were made by replacing 0, 5, 10, 15, and 20% of the fine aggregates with glass cullets. In order to investigate the effects of nanomaterials on the moisture susceptibility of glass asphalt mixtures, the modified Lottman test (AASHTO T283) and the surface free energy (SFE) method were used. The results showed that the addition of nanomaterials improved the adhesive force between asphalt binders and aggregates (crushed glass and aggregates with acidic properties) by reducing the acidic and increasing the basic properties of the modified asphalt binder. Moreover, asphalt modification with nanomaterials increased the initial energy required to separate asphalt binder from the aggregate surface and reduced the risk of moisture damage by increasing the total SFE of asphalt binder.