Study On Dynamic Properties Of Cohesionless Tailings Material Under Different Graduation

As an important facility of mine production,tailings pond plays a key role in environmental protection and sustainable development,and its safe operation is also related to the safety of downstream residents and public property.China is an earthquake-prone country,earthquake liquefaction is also one of the primary causes of tailings dam earthquake damage.Therefore,it is of great practical significance to analyze the stability of tailings dam in seismic state.The key to study the stability of tailings dam is the selection of physical and mechanical parameters and kinetic parameters of tailings materials.Therefore,this paper makes a comprehensive and systematic study on the remodeling of the tailings materials produced by four different grades after ore dressing,taking the tailings reservoir of AoLongshan as the background.Its main contents include:(1)The particle distribution,proportion and permeability of different tailings materials were studied through basic physical characteristics test.Compressibility and shear resistance of tailings are obtained by compression test and direct shear test.The Duncan-Chang parameters of the material were obtained by static triaxial test.(2)By means of ELDyn standard dynamic triaxial test system,dynamic strength characteristics under different stress states are obtained,and the mechanical rules under dynamic load are summarized.(3)For the determination of dynamic deformation characteristic parameters,for four kinds of tailings material,respectively,the dynamic modulus of damping ratio characteristics test,different confining pressure is studied,and the different initial consolidation stress,different tailings material on the influence of deformation parameters.The maximum modulus of motion is obtained by two methods,and its comparison is analyzed.(4)Based on the results of the above experiments,the dynamic stability of tailings reservoir is simulated by using the equivalent linear model.The acceleration reaction and permanent deformation of tailings reservoir under the simulated earthquake state are obtained.The range of liquefaction area is obtained,and the safety of liquefaction area is evaluated by Swedish arc method.Through these works,the dynamic stability of the tailing pond was objectively evaluated.