Experimental study on the shear characteristics of frozen soil-concrete interface under the constant normal stiffness

The interaction between the structure and soil is the key factor for infrastructure stabilization in permafrost engineering. In this study, the shear mechanical behavior of the interface between concrete and permafrost under different normal stiffness, temperature and water content is investigated by using the interface direct shear test under temperature-controlled conditions. The results show that with the increase of temperature and water content, the initial shear stiffness of the interface shear stress-shear displacement curve gradually increases, and the interface shear strength gradually increases. Different normal stiffnesses have a small effect on the morphology of the interfacial shear stress-shear displacement curve, but have a significant effect on the peak shear strength. The peak shear strength increases significantly with the increase of normal stiffness, and this trend is more obvious with the decrease of temperature. The corresponding interfacial cohesion and friction angle also increase with the increase of normal stiffness.