THE INFLUENCE OF DEICING SALT ON AIR VOIDS OF ASPHALT MIXTURE UNDER FREEZE-THAW CYCLE

The extensive use of deicing salt has not only solved the problem of road icing but also had a serious impact on the pavement, reducing its lifespan. In order to deeply understand the impact of deicing salt on the air voids of asphalt mixture in the northwest climate of China, this paper conducted freeze-thaw cycle tests on AC-13 and AC-16 asphalt mixtures under three different deicing salt solutions and three different low-temperature environments, and analyzed the changes in air voids, meanwhile, the Logistic prediction model was used to evaluate the change characteristics of the air voids. The experimental results showed that the air voids of asphalt mixture increased to varying degrees after multiple freeze-thaw cycles; when the temperature was above its freezing point, no frost heave damage occurred, and the air voids increased slowly; when the temperature was below the freezing point, frost heave damage occurred, causing rapid growth and connection of voids in the mixture, and the air voids increased rapidly; the Logistic model showed a good fit with the observed changes in air voids.