摘要：With the continuous implementation of the water diversion project from the Nenjiang River to Baicheng City, and under the effects of multi-field coupling, slope failures occur frequently in the water conveyance canals in the Zhenlai region. To solve this problem, a large number of unconfined compression strength tests under different moisture contents, salt contents and numbers of freezing and thawing cycles, as well as studies of the change in the soil strength, have been conducted based on long-term field observations. It is shown that the saline soil in the study area has the behaviour of a structural soil, in which the unconfined compression strength decreases with increasing moisture content, and there is an inflection point of the strength reduction rate (at a moisture content of 21.9%). With an increase in the salt content, the strength of saline soil presents a fluctuating characteristic, which first decreases and then increases, with a fluctuating inflection point (at a salt content of 1.5%). With an increase in the number of freezing and thawing cycles, the strength of the saline soil shows an exponential decaying trend. The unconfined compression strength becomes stable after ten freezing and thawing cycles, and finally exhibits a residual strength of ~110.0 kPa. These results provide a reference for the stability evaluation of subgrade slope engineering and water conservancy slope engineering.
关键词：Saline soil;Moisture content;Salt content;Freezing and thawing cycle;Unconfined compression strength
