Evaluation of effects of deicing additives on properties of asphalt mixtures

This paper summarizes the results of an experimental study to evaluate the effects of two deicing additives, Verglimit and PlusRide, on the properties of asphalt mixtures in terms of their resistance to rutting, low-temperature cracking, and moisture damage. Verglimit consists mainly of calcium chloride and a small amount of sodium hydroxide. PlusRide is derived from granulating whole tires and tire buffings. These deicers, which are added to the mixture, are currently being used, but their effects on mixture properties are not well established. Mixtures were cured for different periods of time, and the following tests were performed: static and repeated-load indirect tension tests and incremental static-dynamic creep tests. In addition, the VESYS computer program was used to predict the performance of pavements with deicing additives. On the basis of the findings of this study, it appears that Verglimit improves the temperature susceptibility of asphalt concrete and increases its susceptibility to moisture damage because the particles absorb moisture, but that it decreases visual stripping. PlusRide reduced the stiffness of the mixture, thereby increasing its resistance to low-temperature cracking but decreasing its resistance to rutting. The VESYS analysis also predicted that pavements with PlusRide could have a rutting problem. Finally, it was observed that PlusRide reduced the amount of visual stripping by resisting swelling