Beginning in 1985, the Colorado Department of Highways has used geofoam insulation in reconstruction of highway sections damaged by frost heave (Upright 1989). The first such project is an 18 m section of roadway at Rabbit Ears Pass. This was followed by reconstruction with geofoam insulation of a 244 m section of I-70, along the east approach of the Eisenhower Tunnel. Rabbit Ears Pass at elevation 2744 m and Eisenhower Tunnel at elevation 3354 m receive more than 3 m of snow per year and the depth of frost penetration is of the order of 1.8 m. Both sites required annual leveling and patching in spring and experienced undesirable level of frost heave in winter. Additional sections of I-70 totaling some 670 m was reconstructed with geofoam insulation. The geofoam used in the Colorado insulation applications was XPS geofoam of 51 mm thickness and nominal compressive strength of 276 kPa. Inspection of the geofoam after 2 years in service under an average daily traffic of 15,000 vehicle indicated about 3 mm crush. The crush was attributed to have occurred during installation. Geofoam insulation eliminated repetitive repairs for frost heave damaged pavement sections.

References

Upright, W., 1989, "Colorado Fights Frost Heave with Insulation." Public Works, Vol. 120, No. 8, pp.81-82.