Laboratory and Field Evaluation of Anti-Icing Strategies

Departments of transportation use a variety of strategies to maintain roadways effectively during winter while considering a number of factors, such as level of service, cost, infrastructure and environmental impacts, equipment, and weather. The impacts of chemicals on infrastructure, vehicles, and the environment have motivated the State of California to reduce salt usage on highways and to move toward anti-icing strategies, which typically use fewer chemicals to achieve effective results. However, a lack of established recommended dispersal rates, laboratory studies to verify field studies, and an understanding of the science associated with anti-icing principles has slowed full implementation of anti-icing strategies in California. This research effort focused on synthesizing available information regarding winter maintenance best practices and establishing a set of preliminary guidelines to implement anti-icing strategies in California. A qualitative and quantitative evaluation of the performance of five typical anti-icing chemicals was conducted. Performance measures included the temperature at which the snow–pavement bond failed, friction of the pavement surface after snow removal, and snow–pavement bond strength. In general, anti-icing methods used in the laboratory and in full-scale controlled field tests reduced the effort required to remove compacted snow from the pavement surface and improved pavement surface friction after plowing when compared with untreated pavements. A set of guidelines was developed to initiate implementation of anti-icing practices in California. Further assessments are necessary to optimize this methodology on the basis of specific weather conditions and application methods.