Study On The Risk Of Tailing Dam Break

After nearly 60 years of development, China has become the world’s major mining country, metal and nonmetal mine mostly have a tailings facilities. Through investigation and statistics, tailing reservoir in China number, small scale, and most tailings downstream are the living area and the mining industry, once the tailing dam break, not only make the tailings erosion, destruction of ecological environment downstream areas, but also caused huge casualties and property losses. So the tailings dam failure risk assessment and based on the evaluation results, the appropriate risk management measures are necessary necessary of disaster mitigation project and Safe operation of tailings. At present, China tailings dam research focuses on the stability analysis of tailings dam, tailings flood control capacity estimates and tailing dam safety management. More focused on a particular aspect for the tailings dam failure analysis conditions, where there is little risk for the tailings dam to conduct a comprehensive evaluation system. Tailings dam failure risk assessment should include the tailings dam disaster-causing mechanism research, tailings dam failure probability calculation, tailings dam damage evaluation and standards of acceptable risk tailings dam failure, This article from the four aspects of research work, the main research contents and results are as follows:First statistical analysis of domestic and foreign tailings accident and disease type, research formation mechanism of tailings dam failure, summarized the tailings dam break accident patterns and ways to get a total of five categories failure modes and 24 possible outburst paths.Using Catastrophe theory analysis tailings dam slope instability reasons, identify the main factors leading dam break are the cohesion and internal friction angle.. Beijing Heshangyu tailing reservoir for the demonstration project, conducted field and laboratory testing of mechanical properties of tailings, studied tailings accumulation characteristics and mechanical properties of tailings, got the tailings material cohesion and angle of internal friction of mechanical parameters.Second abandon the traditional values of the safety factor calculation method,selectting considered the uncertainty factors probabilistic methods to measure safety. Studied the reliability calculation method for several typical advantages and disadvantages, and ultimately determine the selection Monte Carlo method for slope instability tailings dam failure probability calculation; establish the tailings dam slope failure function, determine the number of simulations, The Monte Carlo calculated the probability of dam failure, considering the correlation between random variables, This method overcomes the traditional matlab subset simulation method can only solve the problem that random variables are normal distribution and independent variables,Physical model and meshing are using ICEM, selecting the SIMPLE algorithm solving methods, using FLUENT software for three-dimensional simulation of the evolution of sand flow.Mathematical model based on Navier-Stokes equations, equation turbulence closure model, using VOF method to track the free surface. Tailings dam losses include economic losses, environmental damage and loss of life, this article focuses on the research of loss of life.By studying domestic and foreign loss of life, improved loss of life estimation methods of description of major hazard census. Taking a tailings pond, for example, simulated dam discharged sand flow evolution, the ultimate impact scope and deep mud at several points of the simulated wererelatively consistent with field observations, proved the validity and correctness of the simulation.Establish personal and social life acceptable risk criteria of tailings dam break. LQI based social acceptability criteria for assessing the Safety input of tailing reservoir, Calculated the rate of tailings current risk to acceptable risk criteria society is willing to pay a fee of 3.3 billion yuan, while China’s current annual tailings can be extracted safety costs roughly only 4.5 million, according to ALARP principle, our country should increase safety costs tailings extraction ratio, increasing the safety input of tailing reservoir, reduce industry risk.The last established the risk evaluation system base on the tailings dam failure probability analysis and dam failing consequence assessment. Applied the set pair analysis to assessment the stability of the tailings dam; using comprehensive factor weighted method to construction the tailings dam break serious consequences evaluation model, the model considered the tailings dam scale, loss of life, economic losses and social environment impact. According to the aforementione d research, the preparation of the tailings dam risk evaluation system software, the system uses a JSP based web development technologies, the software through the specialized agencies of the software testing, test reports annexed to the papers.Take Beijing Heshangyu tailing reservoir for example, analysis the risk of this examples.