Xiaoyi Bauxite Mine Dump Instability Control Engineering Studies

The cost of dumping transportation in open pit is about 40% more of mining total cost. One of important aim of mining production operator is to build safe and economical dumping field. Dumping field in open pit includes in-pit dumping and out-pit dumping. In-pit dumping method can minimize area of land to occupy, improve the efficiency of land utilization, save the cost of mining and relieve the conflict with the peasants in country surrounding. It is important to superficial ground surface open mining which need great floor surface and occupy land fast. The main method to prevent in-pit dumping landslide is to find out the landslide potential mechanics and take effective engineering actions.The researches of this article cover four mining areas in Xiaoyi Bauxite Mine, Shanxi Branch of China Aluminum Corporation. Based on insitu exploration, plentiful researches were carried out to figure out medium parameters of in-pit dumping in Xiaoyi aluminum ore, such as geology and hydrology environmental analysis; production technology investigation; particle size analysis on in-pit dumping; measurement of slope angle of repose; mechanical test of rock-ore bulk media; mechanical test of foundation soil and physical mechanical test of bauxite.Based on the destabilization analysis of in-pit dumping in Xiaoyi Bauxite Mine, following four kinds of mechanical models of potential landslide are set up: i) landslide by natural slope; ii) landslide by leading edge destabilizing of foundation; iii) landslide by leading edge destabilizing of foundation plus trailing edge tension damage; iv) landslide along interface of rock-ore bulk media and foundation, destabilization factor and weight are fixed after analysis on stress distribution characteristics of in-pit dumping by mechanical theoretical analysis and numerical value calculation. The minim safe distance between in-pit dumping slope and stope is made certain by means of theoretical model analysis. It is effective to instruct the safety in production in Xiaoyi aluminum ore.According to the researches result, engineer control actions are brought forward to prevent landslide of in-pit dumping: i) increase internal friction angle between bulk ore rock and groundwork; ii) add earth-retaining wall, increase the slope cubage; iii) compact bulk ore rock, reduce slope height, decrease side squeeze-push stress. It is also effective and preventive actions to monitor the displacement and stress on slope footing and high stress concentration area.