Study On Stability And Dam - Break Simulation Of Tailings Dam In Qiushan Iron Mine Based On PFC ^2D

In this paper, with Qiu Shan iron dry tailings pond project as the research object, trough analyzing the characteristics of the dry tailings pond, using discrete element particle flow code software PFC2D, I established the two-dimensional model based on the micro-parameters calibration of materials, analyzing the stability of the tailings dam with strength reduction, and further studying evolution regularity of sand flow after the dam break, to provide some reference opinions in the later stages of construction and operation. The main research works are as follows:(1) The mesoscopic structure of tailings dam and macroscopic mechanical response, material mesoscopic and macroscopic parameters of qualitative relationship, so that the mechanical properties of particles aggregation embodied is consistent with the macroscopic mechanical properties of materials;(2) The paper analyzed the stability of the tailings dam with strength reduction, calculated the dam safety coefficient is 2.30, compared the result of the particle flow for dam safety coefficient is higher than with Sweden arc method.(3)Based on the analysis of grain flow dam sand flow evolution law, the results show that the surface particles have greater speed than the underlying particles, at the same time, the surface particles in the front of the sand flow have greater speed than in the backend.(4)Due to dam failure moment release huge potential energy, the initial stage of sand dam peak flow velocity of 29.12 m/s, and the following results are obtained, After the sand flow reached the bottom, the sand flow around the average speed of about 5 m/s, maximum speed 13.01 m/s. The sand flow mainly in the slope and the village head position to form a large number of sedimentation, the maximum thickness of 1.3 m, sedimentation village tail direction deposition thickness gradually decreased, and mainly composed of backfilling granule. When the dam caused by piping phenomenon, initial dam body whole sliding, maximum slip velocity of 4.21 m/s, eventually slip distance is 66 m.(5) Qiu Shan iron ore tailings dam disaster severity is moderate, effective measures should be taken to reduce the loss to the greatest extent.