The objective of this project was to develop materials to aid winter maintenance practitioners in making informed decisions on the use of road salts, specifically sodium chloride. To accomplish this, a detailed literature review was conducted, followed by a laboratory investigation that monitored ice formation and precipitation of salt at various concentrations and temperatures. Using the information collected through the previous tasks, a one-page fact sheet and educational video were developed to aid winter maintenance practitioners in how to use and apply information shown in salt phase diagrams. Results from the lab testing produced great images and video of ice and salt crystal formation in solution. Limited ice crystal data was collected and analyzed. Detailed ice crystal formation results could provide significant information to advance this topic. Images of ice crystals with bubbles, potentially filled with salt brine, indicate that the solid phase of ice crystals and salt crystals is not pure, implying that many phases can co-exist. This reinforces the concept that ice formed in the presence of salt brine is weaker than ice formed only in the presence of pure water. When measuring pavement friction following the application of salt brine at various concentrations, the results varied between pavement type, salt concentration, and friction measurement technique. There is value in further refining this, or another, performance test method to assess the influence of salt brine concentration on pavement friction.
