Depth of frost penetration in landfill cover systems

Freezing and thawing of fine-grained soils, of the type typically used for containment applications (i.e., landfill liners, slurry walls, waste pile caps, etc.) has been shown to affect the engineering performance of the soils. Previous research investigations have documented the increase in soil hydraulic conductivity, decrease in strength, and modification of soil porosity following frost penetration into clay soils. Most of these investigations have been conducted in the laboratory, using small-scale test cylinders. The investigations of this study are unique in that they were conducted in the laboratory on large-scale specimens. Thermodynamic and hydraulic measurements obtained during the simulation of freeze/thaw cycles allowed the determination of depth of frost penetration, hydraulic conductivity, and leakage performance of the laboratory model of clay cover liners.