Experimental Study On Permeability Of Fengshuigou Tailing Sand And Its Seepage Simulation

In recent years,with the rapid development of society,tailings dam have gradually increased,and the safety of tailings dam has become more and more important.There are many factors that cause tailings dam accident,such as flood overtopping,seepage and erosion,earthquake and other factors.Seepage is one of the main factors that affect the safety and stability of tailings dam.The permeability coefficient is the main parameter to measure the permeability of the tailings dam.In order to study the permeability of tailing sand,this paper takes Fengshuigou tailings as the research object,and carries out the particle sieving test and the triaxia penetration test on the tailing sand.The tailing sand belongs to the sandy soil with good hydraulic conductivity,so it is necessary to carry out the constant water head penetration test.In the experiment,the initial dry density is1.75g/cm~3?1.80g/cm~3?1.85g/cm~3?1.90g/cm~3,and the surrounding pressure is100KPa?200KPa?300KPa?400KPa,observing the influence of the confining pressure on the permeability coefficient of two kinds of tailing sand at the same initial dry density and the influence of the size of the initial dry density on the permeability coefficient of two kinds of tailing sand at the same confining pressure;keeping the confining pressure fixed and using the main stress difference as the control variable,the pressure of 100 KPa is loaded to 400 KPa,the variation of the permeability coefficient of the tailing sand under the joint action of the confining pressure and the main stress difference is observed;the tailings are loaded step by step to compare the permeability coefficient of the tailings under a single loading and gradual loading;using the void ratio as the control variable,the relationship between the permeability coefficient and the porosity ratio of the tailing sand can be observed.It can be seen that the permeability coefficient of the tailings decreases with the increase of the effective stress and initial dry density,and increases with the increase of the particle size and void ratio;The influence of the coefficient of inhomogeneity and the coefficient of curvature on the tailings sand is less;the permeability coefficient of the first loading is greater than the permeability coefficient of the step by step loading.Using the parameters of the Fengshuigou tailings dam obtained in the experiment and combining the actual situation of the tailings dam,the seepage simulation analysis is carried out on the tailings dam of Fengshuigou,and simulate pore water pressure distribution and safety condition of tailings dam under gravity action and seepage effect,then analyzes the influence of seepage on tailings dam.This paper is of great practical significance to the study of the seepage performance of the tailings sand.