Dynamic Properties Of Tailings And The Stability Analysis Of Tailings Dam

The numbers and the height of tailings dams increase quickly with the increase of the huge need for mineral resources in China. Most of the tailings dams are constructed by upstream method, which leads to high failure probability. Consequently, it is of great importance and urgency to investigate the stability of tailings dams. The two tailings dams of Jiangxi Copper Company Limited are taken as examples. The main research work of this dissertation is as follow:1. The particle distribution and seepage condition of tailings material are investigated by a lot of physical experiments. Compress and strength properties are studied by compress tests, direct tests and triaxial shear experiments.2. The stability reliability method of tailings dam is analyzed by combining reliability theory and traditional safety factor method in stability analysis of tailings dam. A new reliability method is proposed to study the stability of tailings dam. The effect of the shearing strength indexes variation and the density variation of tailings on reliability index is analyzed. The effect of random variables distribution types on stability of tailings dam is also discussed.3. The development of pore-pressure of tailings with the axial strain is studied by the dynamic experiments of tailings. Based on the study results, a practical strain pore-water pressure model is given. The development of pore-pressure with the libration times is analyzed. According to the analysis results, Seed's formula is modified so that the new formula can forecast the dynamic pore-water pressure of saturated tailings material more precisely. The relative density on liquefaction properties of tailings is investigated. An optimal relative density is given to enhance the anti-seismic ability of tailings dam as a design relative density.4. The dynamic responding analysis of tailings dam is carried out using the physical and mechanics parameters of the dynamic experiments of tailings. The effect of earthquake magnitude on the deformation of dam and the development of pore-pressure is analyzed.5. A modification formula is given based on the effect of confining pressure and fines content on dynamic properties of tailings material. A method suitable for tailings dam to determine the liquefaction probability is put forward using the modification formula proposed by this dissertation. A relevant program is implemented with Visual Fortran.The following innovative accomplishments can be obtained from the above research:1.Combining reliability theory with traditional safety factor method, the reliability method is...