Stability Analysis Of Man Zhouli Hongji Tailings Dam And Numerical Simulation Of Dam Break Under Flood

With the continuous improvement of mineral processing technology,the particle size of tailings becomes smaller and smaller,the appearance of extreme environmental conditions and the lax safety management,especially the existence of "overhead reservoir ",which brings great difficulties to prevent and solve the risk of tailings reservoir.Although some achievements have been made in the management and research of tailings reservoir in recent years,the existing achievements are less in practical application,most of them use qualitative analysis method to construct index system to evaluate the overall situation of tailings reservoir,and it is easy to mix subjective factors.The quantitative analysis method is less used,and the parameter selection is single,and the data comparison is lacking,which can not truly reflect the operation of tailings reservoir,especially the calculation of the influence range of tailings flow after tailing dam collapse is almost blank.Aiming at the above problems,this paper analyzes the key information under the condition of HongJi tailings reservoir,identifies the risk factors that affect the tailings dam,calculates the safety factor of the analysis section of the tailings dam,simulates the influence range of sand flow after the tailings dam break,and gives the suggestions for the later operation maintenance and safety management of the tailings reservoir.The specific contents of this paper are mainly carried out from the following aspects:(1)By means of on-site investigation,data checking,data collection and theoretical analysis,the causes of dam failure of tailings dam in recent years are analyzed.(2)According to the relevant data and geological conditions of HongJi tailings reservoir survey,combined with the engineering hydrogeological characteristics,the slope surface of the tailings dam is selected,and the calculation model of the dam body of the tailings reservoir is established according to the original topography,stratigraphic boundary and tailings zoning,and the seepage flow and safety factor under normal and flood conditions of the HongJi tailings dam are calculated.(3)A three-dimensional model of dam body and surrounding environment of HongJi tailings reservoir was established by using the GDEM-PDyna particle dynamics simulation system.Combined with the calculation results of seepage flow and safety factor under flood condition,the evolution range of tailing sand after dam break was simulated.(4)By studying and analyzing the main risk factors affecting the stability of HongJi tailings dam,combining the calculation results of seepage stability and structural stability,as well as the velocity and submergence depth of sand flow passing through the section of sensitive point downstream after dam break,the countermeasures and concrete measures are put forward for the operation and maintenance of HongJi tailings dam and the safety and risk avoidance of downstream residents.