Analysis Of Seepage Characteristics And Stability Of The Dam During The Recovery Of Tailings Resources In Yunna

China is rich in mineral resources,but with the continuous development of social economy,the consumption of mineral resources is gradually increasing,which indirectly leads to the increase of the number of tailing ponds.Tailings pond has the characteristics of high dam body,large potential energy,and generally complex geological conditions.It is a potential hazard and poses a serious threat to the lives and property of the people downstream of the reservoir area.In fact,tailings pond is also a resource pond,especially in the case of large demand for mineral resources,resource extraction of tailings pond can not only reduce hazard,but also realize resource utilization.Therefore,it is imperative to carry out tailings resource extraction.The mining of tailings pond is a dynamic mining process,and its dam will change correspondingly affected by the mining height and water level in the pond,causing safety problems.Therefore,it is of great guiding significance to analyze the seepage characteristics and dam stability of tailings pond during actual project mining.This article takes the Mapaiyi tailings pond as the research object,and combines indoor soil tests,seepage theory,and numerical simulation methods to mainly study the seepage characteristics and stability of the tailings pond during resource extraction.The following conclusions are obtained:(1)Based on the infiltration line and hydraulic gradient of the tailings dam at different mining elevations,it is determined that there will be no damage such as piping or soil flow.According to the seepage field analysis of different mining elevations of Mapiyi Tailings Pond,the results show that the pore water pressure decreases with the reduction of mining elevation,while the hydraulic gradient and seepage velocity increase with the reduction of mining elevation.It is necessary to strengthen the monitoring of water level in the reservoir,but the specific value changes in a small range,and the dam body will not be damaged by seepage under normal conditions.(2)By analyzing the stability of the tailings pond under three different working conditions at different mining elevations,it was found that the safety factor met the standard standards.As the mining elevation of the accumulation dam decreased,the safety factor of the tailings pond dam gradually increased,meeting the conditions for safe mining.However,under different mining elevations,the sliding surface of the dam body appears at the slope of the initial dam and the backfill.The slope of the initial dam should be reinforced again,and the deformation of the initial dam and the slope should be focused on during the tailings mining process.(3)The minimum principal stress and the maximum principal stress are both negative during the mining process,which are mainly affected by compression stress.The maximum shear stress in the reservoir area decreases from bottom to top,mainly affected by gravity.And the pressure and maximum shear stress corresponding to the minimum and maximum principal stresses decrease as the mining elevation decreases.The overall displacement in the reservoir area also changes with the decrease of the height of the accumulation dam,which is mainly concentrated in the area in the reservoir.However,when the mining reaches the initial dam crest,the slope displacement at the side of the tailings pond increases,so it is necessary to strengthen the monitoring of the surrounding mountains of the tailings pond to prevent landslide accidents.During the mining process,although there are certain changes in displacement of the tailings pond,due to the construction characteristics of the mining project in the reservoir area,this displacement can be almost ignored.Therefore,the tailings pond is in a balanced state during the mining process.