Effect of Wicking Fabric on Frost Heave Suppression of Granular Base Course Material

In cold regions, pavement is susceptible to damage caused by freezing and thawing. Most of this damage is attributed to frost heaving in the subgrade layer, which consists of fine-grained soil. On the other hand, cases have been reported of frost damage in base courses that are considered non-frost susceptible. This is primarily thought to occur because the pavement acts as a cover over the soil beneath the pavement, leading to high humidity in the ground under the pavement. In this study, frost-heaving tests were conducted on unsaturated base course materials using a large-scale freezing test apparatus. This study aimed to investigate frost heaving in unsaturated granular course material and verify a method for preventing frost heaving in unsaturated coarse-grained gravel using a geotextile to drain water from the unsaturated gravel. Based on the results of the heaving tests, frost heave occurred in the soil due to the condensation and freezing of water vapor, which resulted in a frost-heave ratio of 20% despite the material being non-frost susceptible soil. The use of wicking fabric (WF) significantly reduced the amount of frost heave. This reduction could be attributed to the lower water content of the gravel caused by the installation of the WF drainage material, which decreased the soil humidity and created an environment that was less conducive to condensation and the freezing of water vapor.