Stability Analysis For The West Dump Landslide Of Yong-Ping Copper Mine

The instability of waste dump in mines would result in disasters, which can influence normal operation and economic benefit of mines. The west dump of Yong-ping copper mine is chosen as the studied project and its stability is researched comprehensively. The geological information such as the occurrence of slope surface, the geological properties of strata are obtained by the site investigation of engineering geology and hydrogeology. On this basis, the physical mechanics properties of rock and soil in the typical region are studied. Physical and mechanical parameters of the bedrock, surface soil and the rock lump in the dumping site are obtained. Engineering disposals are done to these parameters which will provide the basis data for forward mechanics analysis.At present, the analysis methods of slope stability are used to study the stability of the waste dump. It is urgent to explore a new scientific method for research of stability which is suitable for the waste dump. Based on the hypothesis that subjects are deformable bodies, mature numerical simulation method of FLAC^3D in geotechnical engineering field is used, and its results are compared with that of Limit Equilibrium Method. At first, typical cross-section in the dumping site is selected. According to geological information the calculation model that is consistent with practical condition is established, and the analysis on deformation, safety factor and the position of potential sliding surface of the dump slope at current situation is performed. It indicates that safety factor at current height obtained by numerical simulation method and that gained by traditional limit equilibrium Method both are bigger than 1.25, and the slope is at steady state in integer.Augmenting the dumping height is to increase the dump capacity, but more requirements are raised to stability of the dump slope. So the critical height should be determined reasonably. Layered loading in the dumping site is simulated by numerical simulation method of FLAC^3D. It reveals that with increasing of loading height the biggest horizontal displacement and vertical displacement caused by every loading increased gradually, the range of plastic zone expanded and safety factor decreased gradually. When loading height is 128 meter, safety factor will reduce to 1.25 around. According to design requirements safety factor should be bigger than 1.25. So the critical height of the west dump is 128 meter.