中文摘要：

为了直观地描述冻土在冲击加载下的动态力学性能和应力-应变关系,从细观出发,将冻土视为冰颗粒增强的复合材料,建立了基于冰颗粒增强的冻土细观动态本构模型。根据土相在冲击作用下层层破坏的特点,假定冲击层的动模量因冲击损伤而发生变化,在模型中引入了应变率项。利用分离式霍普金森压杆（SHPB）对冻土进行冲击加载实验,通过改变温度和应变率,获得了冻土在不同实验条件下的动态冲击应力-应变曲线。实验结果表明,冻土具有明显的温度效应和应变率效应。模型计算结果与实验结果符合良好,验证了所建立的动态本构模型的合理性和适用性,具有很强的工程应用价值。

英文摘要：

A constitutive model based on ice particulate-reinforced material is developed to visually describe the dynamic mechanical properties and the stress-strain relationship of frozen soil. In view of the fact that soil breaks layer by layer under impact loading,we brought the strain rate into considera- tion as an important factor in constructing the model by assuming that the dynamic modulus of soil changes with strength decreasing step by step. A split Hopkinson pressure bar （SHPB） was used to test the dynamic mechanical response of frozen soil at different temperatures and high strain rates. The experimental results show that frozen soil produces an obvious strain rate effect and temperature effect, and are in good agreement with the theoretical analysis, verifying the constitutive model as both valid and applicable and having significant application value in engineering.