Abstract:

To enhance the emergency response capability of the tailings reservoir, the current dam breach risks were analyzed based on the latest developments in tailings reservoir dam breach simulation technologies and the existing conditions of the facility. The flood overtopping failure mode of the main dam, which leads to the most severe consequences, was selected for detailed analysis. The Flow-3D numerical simulation method was employed to establish a model of the tailings reservoir and surrounding topography. Parameters representing the most unfavorable conditions were used in the simulation to determine the progression of the tailings slurry flow after the dam breach and assess its impact on downstream open areas. The computational grid and boundary conditions were configured with a global rectangular grid size of 2 m. A nested refinement grid of 1 m was added between the tailings reservoir and downstream areas to achieve higher accuracy. Based on the simulation data and the actual terrain of the tailings reservoir, risk levels for downstream areas affected by potential dam breach were classified, and the associated risks were evaluated. The results indicate that the dam breach risk is generally controllable, as the maximum impact distance of tailings under extreme overtopping conditions (650 m) is less than the location of the nearest downstream structure (950 m), resulting in minimal impact on villages. Furthermore, five targeted risk prevention and control measures are proposed.

Key words: tailings reservoir, dam breach simulation, overtopping, risk analysis, risk prevention and control