To study the shear mechanical properties and deformation mechanism of the interface between cemented soil and warm frozen soil, the key parameters are provided for the design and evaluation of cemented soil structure in warm frozen soil ground. In this study, a series of negative temperature direct shear tests of the cast-in-place cemented soil-frozen soil interface were conducted under the influence of different factors. The binary medium model was used to investigate the mechanical stress and deformational mechanisms of the interface, and the damage rate and stress sharing rate functions were introduced. Assuming that the strength of each element of the interface obeyed the Weibull probability distribution, the constitutive equation of the warm frozen soil-cemented soil interface was established. The results showed that the stress-displacement curve of the interface was a strain-softening type, and the entire deformation process of the interface was divided into four stages: the linear elastic, elastic-plastic, softening, and residual stability stages. The constitutive model based on the binary medium theory revealed the micro stress–strain mechanism of the interface and better described the entire stress–displacement process of the interface and the strain softening phenomenon, which can provide a basis for the numerical simulation and theoretical calculation of the structure in the frozen soil ground.

为研究胶结土与暖冻土界面剪切力学特性及变形机理，为暖冻土地层胶结土结构设计与评价提供关键参数。本研究在不同因素的影响下，对现浇胶结土-冻土界面进行了一系列负温直剪试验。二元介质模型用于 研究了界面的机械应力和变形机制，引入了损伤率和应力分担率函数。假设界面各单元强度服从威布尔概率分布，建立暖冻土-胶结土界面本构方程。结果表明，界面应力-位移曲线为应变-软化型，界面整个变形过程分为线弹性、弹塑性、软化和残余稳定四个阶段。基于二元介质理论的本构模型揭示了界面的微观应力-应变机制，更好地描述了界面的整个应力-位移过程和应变软化现象，