关键词: 冻融循环, 季节性冻土, 黄土结构性, 无侧限抗压强度, 侧限压缩, 构度指标

Abstract: According to the structural characteristics of loess in seasonal frozen soil region, based upon the theory of comprehensive structural potential and the thought of configuration indicator, the freezing-thawing configuration indicator is presented. Further, by saturation, freezing-thawing cycles and loading effect，the loess structural property was released to analyze the evolution of its structural property during the process of freezing-thawing cycles. With the high moisture loess in Yangqu City, Shanxi as research object, the unconfined compressive strength test and the confined compression test were carried out under different moisture and freeze-thaw cycles. By the tests, we analyzed the influential law of the saturation and freezing-thawing effects on peak strength of unconfined compressive test. Freezing-thawing configuration indicator was used to reflect the relationship between the compressibility and structural property of loess in this region. The research results show that under different freezing-thawing cycles, the bigger the freezing-thawing configuration indicator is, the stronger the loess structural property is, and also stronger the damage potential of the freezing-thawing and saturation is, otherwise the loess structural property and the damage potential reduce. The freezing-thawing configuration indicator can continuously and regularly reflects the evolution of loess compressibility under different freezing-thawing cycles and moisture contents.

Key words: seasonal frozen soil, structural property, unconfined compressive strength, confined compression, configuration indicator