Model Test Study On Tailings Dam Based On Dynamic Compaction Vibration

In the process of the tailings pond’s actual operation, the blasting vibration in peripheral stope can cause adverse effect on tailings dam. In reality, it is difficult to use explosive as earthquake focus in the model test. In thesis, dynamic compaction vibration is used as the focus to simulate the effect of vibration on tailings dam. The monitoring indicators such as vibration velocity and acceleration are easy to get in experiment, but as important basis of judgment, the macro failure phenomena such as fissure, collapse and liquefaction is difficult to measure. So in thesis, the correlation between vibration velocity, acceleration and macro failure of the tailings dam under the vibration is studied by indoor/outdoor model test and finite element numerical simulation.The indoor shaking table test was implemented in laboratory at first. In this test, the method of control variables was adopted to screen effective variables for outdoor model test, and to determine the reasonable dynamic compaction vibration intensity; Based on the shaking table test, the small tailings model for outdoor test was established and dynamic compaction vibration was used as the focus of outdoor experiment, in order to measure and analyze the conditions and rules of tailings sand’s failure under the effect of dynamic compaction vibration. According to obtained material parameters and the vibration data, the numerical model of the tailings pond in this experiment is established by Geo-studio to simulate the tailings dam failure conditions, and to verify the results of validation test and numerical simulation, and the results of outdoor model test and that of the numerical simulation were contrasted and analyzed.In thesis, the rules of liquefaction and the relative displacement change of tailings sand under dynamic comp action vibration were obtained, and further research on the relationship between change of stress, pore pressure and the macro failure phenomena which contains deformation and liquefaction for tailings sand under the action of vibration was carried out:(1) The moisture content of tailings sand exists a optimal value to achieve the best stability of tailings sand body;(2) Improving the moisture content of tailings sand appropriately can enhance the stability of sand body. The vertical vibration acceleration and vertical relative instantaneous displacement of tailings sand body decrease obviously, and trend of vertical vibration acceleration and relative instantaneous displacement’s increases with dynamic compaction vibration intensity slows down. So the control of seepage line is crucial for the tailings pond;(3) The appropriate dynamic compaction vibration will accelerate the sedimentation and drainage of tailings sand body; it is good to the dense and consolidation of loose sand body. But high intensity will be harmful to the stability of the tailings sand;(4) Under the action of dynamic compaction vibration, when the pore water pressure of tailings sand exceeds 3.09 k Pa, liquefaction may occur;(5)When moisture content of model is below the 13%, the relationship between the peak of instantaneous relative displacement and the vertical vibration acceleration of tailings sand can be represented as:Y =-0.016 +;When moisture content of model is over the 13%, the relationship between the peak of instantaneous relative displacement and the vertical vibration acceleration of tailings sand can be represented as:Y=0.011+26.932().Through study of tailings dam’s security stability under the action of dynamic compaction vibration, failure rules of tailings dam were obtained. It is helpful to government’s supervision and administration of tailings pond’s production safety work and it has a guiding significance on mine enterprises to implement the production safety.