Laboratory studies of gas permeability of frozen soil

Abstract

A preliminary investigation on the gas permeability of frozen soil was conducted in this study. A unique low-temperature permeability testing system was designed and developed. Widely accepted standard procedures were followed to prepare soil samples. A number of experiments were conducted in a cold chamber with controlled temperature. The impact of several parameters upon the gas permeability of frozen soil was investigated. The experiment results indicated that among the parameters examined, moisture content had the most significant impact on the gas permeability of frozen soil and the effect of temperature was less significant than that of moisture content. It was also found that there seemed to be a transition zone around 10% of moisture content. With moisture content above this level, the permeability was less sensitive to temperature change, while below this level the permeability was more sensitive to temperature change. Another finding was that the permeability increased when the temperature fell below 20ʻF. In addition, applying loads decreased permeability by 10% to 30% dependent on the setting of other parameters. Some suggestions for improvement of the experiments and future research works were also presented.