Mechanical characteristics and strength model of ice-rock interface based on small-scale centrifugal tests

The mechanical interaction between glaciers and the underlying bedrock is a primary factor influencing ice avalanche disasters. However, research on the mechanical properties of the ice-rock interface remains limited. To further investigate the key mechanisms involved in the initiation of ice avalanches in high-altitude cold regions and to elucidate the main controlling factors and their underlying principles, this study designed and developed a small high-speed centrifuge device suitable for conducting debonding tests at the ice-rock interface. Systematic tests on the bonding strength of the ice-rock interface were carried out under various conditions. The main findings are as follows: (1) The centrifuge device demonstrates high testing efficiency and low data dispersion, facilitating strength tests of the ice-rock interface under multiple conditions, including tension, pure shear, and compressive shear. (2) The bonding strength of the ice-rock interface is closely related to temperature, rock surface roughness, and rock lithology. Lower temperatures lead to greater bonding strength, exhibiting an overall linear relationship. The bonding strength shows a nonlinear positive correlation with rock surface roughness; however, when roughness exceeds a certain threshold, the formation of interface cavities inhibits further increases in bonding strength. Rock lithology affects bonding strength with ice through factors such as porosity and mineral hydrophilicity. (3) A computational model for the bonding strength of the ice-rock interface was established, clarifying the quantitative relationships among bonding strength, temperature, roughness, and normal pressure. This study provides a novel experimental method for analyzing the mechanical properties of the ice-rock interface, and the results offer a quantitative basis for understanding the mechanisms of disaster and assessing the risks of ice avalanches in high-altitude cold regions.