Study On Slope Stability Of Residual Coal Mining In South Slope Of Yuanbaoshan Open-pit Mine

Slope stability is the precondition in the process of open pit mining,which directly impact on normal production and safety of open pit mine.Open pit slope is a dynamic slope,changing along with mining and opening development.Since 1990,Yuanbaoshan open-pit mine launched its constructions,south slope took place landslides during the drawdown of stope slope.The problem of south slope stability will be more outstanding with residual coal mining.For recycling resources as much as possible under the premise of ensuring safety,how to determine the space position relation of the working slope,the inner dump site and the non-working slope is a urgent issue.In this paper,with the south slope of Yuanbaoshan open-pit mine as the engineering background,slope stability of residual coal mining in south slope of Yuanbaoshan open-pit mine is studied with field investigation,data collection,theoretical analysis,rigid body limit equilibrium and numerical simulation methods.Proposing the method that parameters is optimized stage by stage about dip bedded compound seam slope,and applying the method to make section shape of the south slope.Therefore,the impact of the engineering location n the excavation angle and the weak layer exposure length on landslide model and the three-dimensional slope stability are studied by numerical simulating,then determining the spatial form of south remnant slope in the end.The results show that weak layer is the main factor that affects the slope stability.The south slope of Yuanbaoshan open-pit mine is easily bedded and cutted layer sliding.Affected by the attitude of the weak layer,each of bench width of two-dimensional is not contant.The slope stability will drop in the increase of the weak layer exposure length,and the slope stability will not be changed when the exposure length exceeds a critical value.The impact of the excavation angle on the slope stability is gradually highlighted with the engineering location changing,and the slope stability will drop in the increase of the excavation angle.