Research On Physical Mechanism And Numerical Simulation Of Tailings Dam Slope Failure

At the end of 2015,China has 8,869 tailings ponds including a total of 1,425 "head tailings pond",and the number of tailing ponds was among the highest in the world.As the most important part of mine engineering,tailings ponds have the characteristics of high potential energy,high risk,and high accident severity.By the statistics,tailings dam instability accidents accounts for 60% of the total number of tailings dam accidents in the past year.It is imminent to take effective measures to reduce the accidents.This paper studies the instability mechanism and numerical simulation methods of tailings dam.The factors causing the instability of the tailings dam are proposed,the evolution rules of the overburden dam are analyzed,and the variation laws of the slope stability factor and shear strength of the discrete element method and the limit equilibrium method are compared and analyzed.The conclusion as follows:(1)The causes of instability of the tailings pond was be comprehensive analyzed by analysis the hazards of the sliding patterns of the four types of tailings ponds,including shallow sliding,deep sliding,integral sliding,and polygonal linear sliding based on analysis global tailings pond accidents and its causes,the characteristics and differences in the safety management work of the tailings ponds in China and other countries,the different evolutionary laws of the stabilization results.(2)Flooding overtopping experiment was tested to study the development rule of the breach in the dam collapse process.The results shown that the development degree of the dam breach depends on the erosion effect of the diffuse flow,and the discharge flow curve is affected by the erosion of water flow and the expansion of the rip.With the flushing speed increases,the discharge expands and the discharge flow suddenly increases.Slower water scouring speed,lower crater flow rate,and eventually stabilized.(3)There is a consistency between the slope stability factor and the shear strength change law of the discrete element method and the limit equilibrium method.When the shear strength value of the early stage decreases by a small margin,the slope stability coefficient changes to some extent with the shear strength changes.After the reduction of the value increases,the slope stability coefficient and the shear strength change linearly.Tailings dam instability accidents may be caused at all stages of the tailings pond life cycle.It has significant social benefits that the risk indicator for tailing dam instability,the law of stability changes to improve the technical content of safe production management for tailings dams slope and prevent the occurrence of serious tailings accidents.