Effects of fine contents on the mechanical response of frozen sands

Abstract

Recently, the development of the natural gas pipeline in Russia as well as the recent construction of the second Korean Antarctic research station, the Jangbogo station provide the research interests on the behavior of the permafrost ground. In ISOPE 2013 (Chae et al., 2013), the experimental research on the mechanical responses of frozen sands was presented. In the previous research, the testing conditions and experimental set up for the research on the frozen soils were the main issues. As a succeeding research on the frozen soils, the mechanical responses of frozen sands with 0, 5, 10 and 15% of fine contents are investigated via unconfined compression tests at -5, -10 and -15°C. The poorly graded (SP) Joomunjin (Korea) sand and kaolinite, silt with low plasticity (ML) are used for the preparation of the frozen specimens. The mechanical responses of the tested soils are investigated via unconfined compression tests in the temperature controlled laboratory and analyzed in terms of peak unconfined compressive strength and secant modulus at 50% of the peak strength. As the fine contents increase, the unfrozen water contents increase and thus the strength and stiffness of frozen soils decrease. The increment of the stiffness and strength due to the decreasing temperature varies with the fine contents. Copyright © 2015 by the International Society of Offshore and Polar Engineers (ISOPE).