New Insights into Ice Dam Failure Using Fracture Mechanics Analysis

The study of ice dam failure characteristics holds significant engineering value for managing glacial lake outburst floods. However, the coupled effects of subglacial tunnels and cracks on ice dam failure remain poorly understood. This paper develops a mechanical model of an ice dam subjected to reservoir water pressure, grounded in elasticity and fracture mechanics. The stress distribution within the ice dam and an analytical solution for the stress intensity factor are derived. Numerical simulations are performed to validate the analytical solution, and the model's mechanical response under varying crack distributions is analyzed. Furthermore, factors affecting the stability of the ice dam are systematically examined. The results reveal that the expansion of subglacial tunnels, which triggers crack propagation at the ice dam's top, is the primary driver of structural failure. Larger subglacial tunnel radii, greater ice dam heights, and reduced ice dam thickness intensify stress concentration, increasing the likelihood of tensile failure on both sides of the subglacial tunnel. This study provides novel insights into ice dam failure mechanisms and establishes a theoretical framework for evaluating ice dam stability.