Frost Action in Canadian Railways: A Review of Assessment and Treatment Methods

Railways constructed in cold regions can experience localized frost heave in the winter as well as track softening during the spring thaw. These phenomena are great challenges for road and railway foundations on seasonally frozen ground and must be considered by railway operators. To address these problems, temporary wooden shims can be used to smooth existing tracks; reductions in train speeds may also be mandated. The degree of susceptibility of a given section of a track to frost can be determined by considering the main preconditions allowing heave and frost to occur. This study reviews several frost susceptibility surveys that show the correlation between soil properties and laboratory results of frost heave tests. A summary of treatment methods for frost action is presented and a straightforward design procedure is provided to first evaluate the frost susceptibility of soils and the frost hazard potential in Canada as well as predict the frost penetration depth, and then select the appropriate frost-treatment method based on previous studies and standards. The outcome of this study is a five-step tool that can be applied by Canadian engineers to first evaluate the frost susceptibility degrees of soils based on the soil properties in each province and then select the appropriate treatment method considering the frost hazard potential.