Abstract This paper presents a comprehensive research about the coupled influence of freeze-thaw procedure and stress condition on cyclic mechanical properties of the frozen clay. According to cyclic test data of frozen clay at the temperature −10 °C, dynamic responses in various cases of confining pressures, cyclic loading amplitudes and freeze-thaw cycles are investigated in detail. Cyclic stress ratio is used to investigate the coupling effects of the freeze-thaw procedure, confining pressure and dynamic loading amplitude on permanent strain curves under same dynamic cycle-time. The permanent axial strain raises with increase of cyclic stress ratio. An empirical formula is presented to quantitatively characterize the coupled effects on the permanent deformation of frozen samples. Two-stage evolution features of resilient modulus in the cyclic loading process are clearly observed under all confining pressures and dynamic stress amplitudes. The inflection points of two-stage curves are rationally considered as the endpoints for the post-compaction compression stage. The axial strain value at this inflection point is defined as the yield strain under cyclic loading conditions. The yield strain point roughly occur around 3000th-3900th loading cycles. When the freeze-thaw cycled reaches at 6, the loading cycles at the inflection point (yield point) were approximate 3300. There was no obvious freeze-thaw cycle threshold for the dynamic elastic properties of frozen samples. Finally, based on the analysis for the loading cycle numbers at those yield points, the dynamic strength curves of samples under different confining pressures can be established.

中文翻译：

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冻融循环动态循环载荷下冻结粘土的力学行为

摘要 本文综合研究了冻融过程和应力条件对冻土循环力学性能的耦合影响。根据-10℃冻土循环试验数据，详细研究了各种围压、循环载荷幅值和冻融循环情况下的动力响应。循环应力比用于研究在相同动态循环时间下冻融过程、围压和动态加载幅度对永久应变曲线的耦合效应。永久轴向应变随着循环应力比的增加而增加。提出了一个经验公式来定量表征对冷冻样品永久变形的耦合影响。在所有围压和动态应力幅值下，都清楚地观察到了循环加载过程中弹性模量的两阶段演化特征。两阶段曲线的拐点被合理地认为是后压实压缩阶段的端点。该拐点处的轴向应变值定义为循环加载条件下的屈服应变。屈服应变点大致出现在第 3000-3900 次加载循环左右。当冻融循环达到6时，拐点（屈服点）的加载循环约为3300。冷冻样品的动态弹性特性没有明显的冻融循环阈值。最后，基于对这些屈服点加载循环数的分析，