A typical clayey loess obtained along the ShenyangHa’erbin Express Railway was taken as a case study. The effect of nonsaturated water content

temperature

freezing rate

supplying water condition and freezingthawing circulation on the frost susceptibility of soil were investigated with freezing and thawing experiments. It was shown that in the closed system

the frost heaving ratio of unsaturated soil increased with water content increasing and eventually reached a stable value. And for the soil samples with low water content

the frozenheave rate increased with the decrease of temperature. While for the samples with relatively higher water content

the frozenheave rate decreased with the increase of temperature. As regards the open system

the frost heaving ratio increased with a growing gradient as the freezing rate decreased. Waterfeeding made the frost heave amount increase significantly

while less with the increase of water content. The frost heave deformation showed exponential decline trend with the increase the frequency of freezing and thawing for soil with low dry density

while exponential increase for the soil with high dry density.