Evaluation of Performance Deterioration Characteristics of Asphalt Mixture in Corrosion Environment Formed by Snow-Melting Agents

To simulate the influence of the corrosion environment caused by snow-melting agent on pavement, an asphalt mixture was treated by dry-wet cycle in a NaCl solution with various concentrations. The rutting test, bending test, freeze-thaw splitting test, immersion Hamburg wheel-track test, industrial computed tomography (ICT) test, and scanning electron microscope (SEM) test were conducted to evaluate the adverse effect of snow-melting agent on road performance, durability, and the microstructural characteristics of SMA13, AC13, and SUP13 asphalt mixtures. The damage mechanism of performance for asphalt mixtures in a corrosion environment was also discussed. The results show that the road performance and durability of SMA13, SUP13, and AC13 asphalt mixtures decrease by various extents after being treated by the method of dry-wet cycle in chloride salt solution. Among the three kinds of asphalt mixture, SMA13 shows the best resistance to the corrosion of NaCl solution, followed by SUP13 and AC13. After being treated in salt solution, the void parameters such as total void volume, average void volume, equivalent void diameter, and air void of a Marshall specimen grow fast first and then tend to stabilize. The crystallization expansion of NaCl crystals results in structural damage inside the mixture, and then the strength of the asphalt mixture greatly declines, leading to the deterioration of road performance and durability in a salt corrosion environment. SMA13 asphalt mixture is recommended for pavement surface layers where the snow-melting agent is often used.