A Modified Freeze-Thaw Laboratory Test for Pavement Sub Soils Affected by De-icing Chemicals

Abstract

De-icing chemicals are the most effective and cheap method to prevent winter slipperiness on pavement surfaces in urban settings. Analysis of existing experimental studies and theoretical methods shows that solutions of de-icing chemicals run off surfaces and are deposited in adjacent soils. However, there is a lack of knowledge about the effect of de-icing chemicals on the engineering properties of pavement sub soils, where the de-icing agents may penetrate beneath the pavement surface. This is a particular issue as pavement surfaces typically cool and warm at a faster rate than surrounding areas. In particular, during seasonal freeze-thaw cycles, the lower freezing point of the chemical solution may induce moisture migration toward a freezing front within the sub soil, leading to increased heave potential, and subsequent thaw collapse.The paper describes an experimental study that simulates the movement of water and de-icing solution from the deposition area upward to the highway’s sub base. The chemical effect of de-icing solutions on the strength characteristic, water and chemical content of each 10 cm layer of tested soil column will be assessed by in situ measurement and post-experiment analysis. In the long run the impact of the de-icing chemicals precipitation on the bearing capacity and deformation of sub base soils of roads will be evaluated.