Research on deicing performance and environmental impact of anti-freezing asphalt mixtures

Abstract

Snow and ice on pavement surface can cause a significant safety concern for drivers. This research investigates the deicing performance of the asphalt mixtures containing a self-prepared salt-storage additive (SSA), as well as their environmental impacts. A pull-off test was developed to evaluate the adhesion between the ice layer and asphalt mixture surface. The self-prepared SSA was incorporated into the asphalt mixtures by replacing mineral filler at percentages of 0 %, 20 %, 50 %, and 100 % by volume. The influence of self-prepared SSA on the pavement performance of asphalt mixtures was firstly investigated in this study, including the high-temperature stability, low-temperature performance, and water stability. The deicing performance of the asphalt mixtures containing self-prepared SSA and commercial product was determined by using the freezing point tests, ice-melting tests, and self-designed pull-off tests. To evaluate the environmental impacts of those anti-freezing asphalt mixtures, corrosion tests and seed germination tests were also employed in this study. Testing results showed that the addition of self-prepared SSA compromised the pavement performance of asphalt mixtures, but all measured properties met the specified requirements. The self-prepared SSA can effectively reduce the freezing point of the asphalt mixtures and shorten the ice melting time by 30 %, which has a similar or even better deicing effect as compared to the commercial salt-storage additive. Notably, the pull-off tests showed that the self-prepared SSA can significantly reduce the adhesion force between ice layer and asphalt mixture surface. The environmental impacts of asphalt mixtures containing self-prepared SSA were found to be within a reasonable range.