Numerical Simulation of Tailings Flow from Dam Failure over Complex Terrain

Abstract

A tailings dam failure can lead to disastrous impacts on people’s livelihood and the surrounding ecological environment. Due to interactions among water, tailings and ground, the mechanism of a tailings flow is more complicated than that of a flood flow. In this paper, the tailings flow is regarded as a homogeneous and incompressible non-Newtonian fluid. Its rheological properties were studied through rheological tests conforming to the Bingham model. The rheological parameters were further used in a Computational Fluid Dynamics (CFD) simulation over complex terrain to explore the tailings flow characteristics. The method was validated with experimental results of a non-Newtonian dam-break flow from literature. The flow characteristics, including flow velocity, runout distance, inundation area and depth, were analyzed in the case of the Dagangding tailings dam. The results showed that the downstream railway and village would not be affected in a conservative scenario. Finally, the effects of two measures for preventing tailings flow hazards were discussed. Setting the check dam and planting grasses and trees can effectively mitigate the damage of tailings flow.