Abstract: In order to prevent liquefaction,which is dangerous to the stability of the tailings dam. Based on southwest high earthquake a fine grained tailings dam as an example, the fine grain of backfilling dynamic shear modulus and damping ratio, and related test parameters for foundation, according to the approximate artificial fitting of seismic wave field as the power input load, equivalent cyclic shear stress compared with anti liquefaction shear as the basis of liquefaction discrimination, with the help of the schedule stress by means of finite element method, the detailed analysis of the high earthquake liquefaction of fine grained tailings area and dynamic stability. The results show that the liquefaction area is mainly concentrated under the water level at the end of the reservoir. In dynamic stability coefficient is compared with the pseudo-static method, stability coefficient is small, only a seismic wave action and pseudo-static method to calculate the stability coefficient of basic quite, which also shows that dynamic time history method in analysis of tailings dam in high earthquake dynamic stability, more in line with the actual seismic dynamic process, and superior to the traditional pseudo-static method.

Key words: Fine grained tailings, High earthquake region, Dynamic time history method, Liquefied area, Dynamic stability