Study On The Stability Of The Increased Inner Disposal Field In Weijiamao Open-pit Mine

The instability of dumping site can affect the normal production,personnel and equipment safety of Open Stope and dumping site.Open-pit dump is often affected by land requisition and can not meet production requirements according to design requirements.Taking Weijiamao open-pit mine as the research background,we consider to increase the internal discharge by connecting the external dump and the internal dump in order to reduce the difficulty of land requisition by external discharge and the influence of cost.In order to ensure the stability of the slope of the inner dump,the stability of the slope of the inner dump in Weijiamao Open pit mine is studied According to the present situation of Engineering Geology,the theoretical analysis,rigid body limit equilibrium analysis method and three-dimensional numerical simulation method are comprehensively used The slope stability and its related problems in the area of east side crusher and north side flood drainage canal of the first mining area are studied deeply,and the space shortage of the dump is solved.According to the design specifications,the safety reserve coefficient is determined to be 1.30.Using the limit equilibrium analysis method,the stability of the slope of the drainage site and the internal disposal site after increasing were calculated.The stability of the slope of the inner drainage site was calculated by selecting the section 1-1,section 2-2,section 3-3 and section 4-4,and the stability coefficient of the slope before and after the increase was greater than the safety reserve coefficient of 1.3,indicating that the slope was in a stable state.The slope morphology of the North side and the Earth side was optimized,and the width of 1208 plate was determined to be 35m.Using FLAC~3DD numerical simulation software,a three-dimensional numerical model of the eastern slope and a three-dimensional numerical model of the southern slope were established.and the distribution characteristics of stress,displacement,and plastic zone during slope instability were analyzed.From the displacement cloud diagram and the stress cloud map of the numerical simulation results,it can be shown that the displacement of the rock and soil at the slope shoulder is the largest,and the displacement of the sliding body is mainly horizontal.The slope has a circular arc landslide,and the stability coefficients of the two models are calculated.1.58 and 1.46,It satisfies the requirement of safety reserve coefficient and is consistent with the calculation results of rigid body limit balance method.The analysis results show that the height of the inner drainage field can be increased to 1280,The height of the slope increased to 260m,and the internal and external drainage fields can be coordinated.This study provides a new way to solve the problem of insufficient dumping space.The research method and the research conclusion have a strong theoretical guidance and practical application value to the open-pit coal mine cases with similar engineering conditions.