Study On The Evolution Process Of Discharge Sand Flow After Tailing Dam Instantaneously Break

Tailing pond is an important infrastructure of mining production,but also a dangerous source with high potential energy.Once tailing pond dam break,the high potential energy of the tailing will flow down to the downstream area,it will brings the serious disaster.Therefore,the systematic study the discharge sand flow after tailing pond dam break and predicting the possible damage of tailing pond dam break,has important significance for the work of disaster prevention and mitigation and protect people's lives and property safety.This paper bases on the research background of Majiagou tailing pond project,uses the analysis method of the indoor similarity model test and numerical simulation combined,detailed study on the evolution process of discharge sand flow in the downstream area after tailing pond dam break.By reducing the bottom elevation of the open channel and expanding the width of the open channel in order to reduce the influence of dam-break sand flow in the downstream area.The main achievements of this paper are as follows:(1)The paper introduces the basic situation of the Majiagou tailing pond in detail,and obtains the basic physical and mechanical parameters of the tailing through the indoor laboratory soil test,which provides the basic data for the study on the evolution process of the dam-break sand flow.(2)According to the design data and electronic topographic map of Majiagou tailing pond,a indoor fine 3D similar model is established.Using the similar model of the tailing pond dam-break and applying the principle of similarity theory,dam-break test was carried out,By recording and monitoring the movement process of discharge sand flow in the downstream area after tailing pond dam break,it detailed analyzed the flow of the breach and open channel,the evolution rate of dam-break sand flow and the time to reach the downstream along the area,water level elevation,the maximum submergence area of water and tailing deposition,and obtained the evolution law of dam-break sand flow.(3)the three-dimensional model of dam-break is established based on N-S equation and RNG turbulence model of water flow,the movement of tailing is calculated by the bed load and suspended control equation,using the Tru-VOF technology to track the dynamic change of water level,the dam-break of Majiagou tailing pond is simulated.And the results of numerical simulation and model test results are compared and analyzed.The results show,in addition to the evolution time of the dam-break water flow does not meet the model similarity conditions,the difference of the results can meet the engineering requirements.it verifies that Flow3 D software can well simulate the tailing pond dam-break and other engineering problems.(4)By changing the bottom elevation and width of open channel,discussing that the impact extent of disaster in the downstream area.The results show that expanding the width of the open channel can greatly increase the drainage capacity of the open channel,reduce the downstream area water level and the transportation distance of tailing in the downstream area.But reducing bottom elevation of the open channel has little impact on the evolution of dam-break sand flow in the downstream area,disaster prevention and reduction effect is not good.The research results can provide data support for the disaster prevention and evaluation of Majiagou tailing pond,and can also provide reference for other similar projects.