Measurement of unfrozen water in unsaturated soil with pulse NMR

抄録

This study aims to reveal the effect of suction on the ice formation in unsaturated soil. Unfrozen water content was measured by a pulse NMR for the saturated and unsaturated silt prepared by vapor pressure technique. Based on the data, for the unsaturated frozen soil with the initial high water content, the unfrozen water content of the unsaturated soil has the same tendency as that of saturated soil. While, water rarely freezes in case of low water content. Water cannot freeze less than the water content corresponding to the beginning of residual water saturation for all conditions. Furthermore, the unfrozen water ratio of the unsaturated soil is higher than that of the saturated soil. Therefore, these results revealed that suction has strong influence on the ice formation in unsaturated soil.