Research On The Dynamic Process Of Tailings Pond Overcrowding Dam And Its Post-breaking Effect

The tailings pond is an indispensable facility in the production and operation of the mine.Once the dam body is unstable and damaged,it will pose a serious threat to the lives and property of the downstream people and cause environmental disasters.However,the tailings slurry after the collapse of the tailings reservoir is a complex water-sand mixture,the influencing factors are complex and variable,and the interaction between various factors makes the influence range and the degree of disaster of the tailings flow after the collapse.Forecasts have strong uncertainties.At present,the research on the evolution process and impact evaluation of mud-sand flow after tailings reservoir collapse is still lack of systematicity.Therefore,based on the actual engineering background,this paper uses the indoor experiment,model experiment,numerical simulation and theoretical analysis to carry out the tail.Based on the field investigation and related literatures,the evolution and sedimentation law of the tailwater flow in different downstream riverbeds are obtained,and the impact force and maximum flow velocity of the tailings flow to the downstream are revealed.The relationship between the flow and the depth of the flow,and the extent of the impact of the tailings flow,is drawn to provide an important basis for the evaluation of the impact range of the tailings pond and the relocation of downstream villages to ensure the safety of life and property of downstream personnel.Through the above research,the following conclusions are obtained:1)The variation of flowability and yield stress of fine-grain content and concentration factors on tailings slurry was studied,and the nonlinear characteristics of yield stress of tailings slurry with concentration were revealed,and the fines in the tailings slurry were fine.As the particle content increases,the viscosity increases,which in turn leads to an increase in yield stress.2)Through the indoor dam model experiment,the influence of the dam material of the tailings pond on the disaster area and the flow characteristics of the dam break tail flow is studied.The study shows that the tailings particle size affects the deposition and disaster degree of the downstream tailings;that is,with the increase of coarse tailings,the deposition amount and sediment thickness of the tailings are significantly increased,especially in the upstream and downstream of the circulation area.Obviously,this is mainly because the deposition distance of the fine particle tailings is larger than that of the coarse particle tailings particles.In the case of dam construction with tailings at the same level,the difference between the maximum impact height of the downstream tailings flow in the downstream section and the final deposition thickness of the sectionincreases first and then decreases.3)Based on FLO-2D software,the dynamic numerical simulation of the evolution process of the dam breakwater flow is carried out,and the evolution characteristics of the dam break tail flow under different riverbed slope conditions are analyzed.The results show that the area of ??tailings flow in the upstream and downstream terrain of the circulation area is relatively large;the maximum submerged range and final submerged range of the downstream increase with the increase of the downstream riverbed slope,and the tailing tail sand is mainly deposited in front of the dam.The nearby villages and downstream circulation areas are flat.4)The downstream construction of the slag dam can effectively reduce the damage degree of the downstream tailings flow to the downstream.In this paper,the FLO-2D software is used to analyze the fluidity and evolution of the tailings flow when the slag dam conditions are set.The analysis results show that with the increase of the distance from the initial dam to the initial dam,the average sediment thickness of the tailings in the slag dam gradually decreases.With the increase of the height of the slag dam,the flow velocity and impact of the downstream tailings flow to the downstream The range of forces and deposits is correspondingly reduced.5)Based on the unascertained mathematical theory,the influence degree of the downstream tailings flow on the downstream disaster caused by the tailings pond dam break is studied,and the influence degree of the tailings reservoir downstream of the tailings pond under the different factors is established.The model,through the confirmation of the evaluation indicators,the weighting of the evaluation,the use of confidence to determine the risk of the prototype area,thus providing an important basis for the evaluation of the impact range of the tailings pond disaster and the relocation of downstream villages,to ensure the safety of life and property of downstream personnel.