THE VARIATION OF PHYSICAL PROPERTIES IN FROZEN SOILS AT VARIOUS FREEZING TEMPERATURES

摘要

Due to the recent climate change, the colder and longer winter is expected in Korea. Besides, the recent participation agreement on the development of the natural gas pipeline in Russia and construction of the second Korean Antarctic research station, the Jangbogo station changes the research interests from the seasonally frozen ground to the permafrost ground. The recent development of the site investigation techniques using wave propagation and electrical resistivity enabled engineers to evaluate the physical properties of the frozen soils and further correlate them to the mechanical properties. However, the physical properties of the frozen ground change when the water in the soil solidifies to ice; this change is particularly notable between 0 and -10°C. Therefore, the physical property changes due to freezing needs to be investigated in terms of wave propagation characteristics and electrical resistivity with regard to the various freezing temperatures. In this study, the characteristics of wave propagation and electrical resistivity of frozen soils are investigated under various sub-zero temperatures. The characteristics of wave propagations are analyzed in terms of compression and shear wave velocities. The electrical resistivity is measured under various sub-zero temperatures to understand the effects of ice, which will further provide the valuable information about the location of the active layer. Furthermore, the evaluated physical properties can be used as basic data for the evaluation of the mechanical properties such as strength and stiffness.