Study On Slope Stability And Shape Optimization Of Coal Mining In First Mining Area Top Slope Of HuoLinHe South Open-pit Mine

Slope stability is a prerequisite for mining of open-pit coal mines,which directly affects the normal production and safety of open pit mines.The open-pit mine slope is a dynamically developed slope that is constantly changing as a result of stripping works.With the mining of the Huolinhe South open pit mine,It is important to determine the slope shape is line with the safety and economic exploitation of coal resources.With the gradual development of mining work,first mining area top slope due to the existence of a number of weak layer,stability problem of top slope will become more prominent,In the case of deep slopes with the plan of cross exploitation and inner dumping,it is necessary to ensure the safety and recycling of resources as much as possible,to determine the location of the exploitation,the internal inner dumping position and the exposure length of weak layers.In this paper,For the stability of the first mining area top slope is studied by site investigation and data collection,theoretical analysis,rigid body limit equilibrium and numerical simulation.The method of step-by-step parameters optimization of multi-coal-layer slope is proposed and applied,and determine the parameters of top slope;From the three-dimensional point of view.the spatial pattern of the slope is determined by the combination of 2D and 3D method.The influence of the weak layer exposure on the landslide pattern and the slope stability is studied by numerical simulation.Finally,the shape of the top slope is determine.The results show that the weak layer is the main factor to control the stability of the first mining top slope area of Huolinhe south open-pit mine,and it is easy to slide along shear arc and weak layer.Affected by the occurrence of weak layer,The width of the flat plate is not constant for all stages of the optimized two-dimensional slope.The stability of the slope decreases with the increase of the exposure length of the weak layer,which is negative exponential law,when the value of exposure length is 250m,the 3D effect of the slope disappears and the stability coefficient no longer changes.