以K0固结后在受载状态下冻结的冻结土体为研究对象,利用代表土体刚度特征的割线弹性模量,研究了在应变不超过0.5%时,深部人工冻土的刚度随应变发展变化的趋势,分析了造成K0固结后冻结土体杨氏模量与未冻土体杨氏模量较大差异的原因,讨论了冻结温度和初始围压对K0固结后在受载状态下冻结的冻土刚度大小的影响以及对冻土屈服后刚度衰减速度的影响.
The small-strain stiffness characteristic of artificially frozen soil in deep alluvium was investigated at different initial confining pressures and frozen temperatures by secant Young's modulus representing the soil stiffness. The influence of freezing on stiffness is investigated by comparing the behavior of frozen and unfrozen soils with similar conditions. It is observed that the variation of Young's modulus E0 with the confining pressure, represented the magnitude of the initial stiffness, mainly depends on the variation of ice in frozen soils with the confining pressure, not on the soil itself. The frozen soils secant Young's modulus may decay with increasing strain after keeping a stage of constant value, the threshold yield strain was found to be approximately 0.05 % for all tested conditions. On the other hand, the stiffness of studied frozen soils and its degradation was heavily response to the initial confining pressure amplitude and temperature fluctuation.