Effect of Preparation Methods for Salt-Storage Additives on the Properties of Epoxy Asphalt Mixture

Reducing the adverse effects of incorporating deicing salt additives on the performance of antifreeze asphalt mixtures represents one of the key research directions in antifreeze pavement technology. In this study, five types of salt-storage additives were synthesized using different methods and incorporated into epoxy asphalt mixtures. Their surface morphology was characterized via scanning electron microscopy (SEM), and their slow-release properties were evaluated by continuous immersion tests. The curing degree of epoxy asphalt mortar was analyzed using Fourier transform infrared spectroscopy (FTIR), and the mechanical properties were assessed. Furthermore, the road performance of the prepared salt-storage additive-modified epoxy asphalt mixtures was examined. The results demonstrated that the release time of the salt-storage additive fabricated via bottom-spray coating (SSA-E) was prolonged by 51.1 h compared to the untreated additive (SSA-A). Compared to SSA-A epoxy asphalt mortar, the tensile strength, shear strength, and adhesion strength of SSA-E epoxy asphalt mortar increased by 43.37, 50.27, and 33.85%, respectively. Additionally, the Marshall stability and dynamic stability of the SSA-E epoxy asphalt mixture exhibited 84.48 and 60.08% improvement, respectively, compared to SSA-A. These findings indicate that a more complete coating of deicing salt has less influence on the properties of epoxy asphalt mortar and epoxy asphalt mixtures. This study provides an effective approach to mitigate the adverse effects of deicing salts on the performance of asphalt mixtures.