Study On Open Pit Stripping Exploitation Technology In Underground Goaf Of Da Miao Iron Mine

After several years of underground mining,da miao iron mine has formed a lot of goafs,if they do not deal with these goaf areas in time,if the roof takes place,it will produce severe rock burst,causing major land pressure disaster,pose a threat to mine safety in production,severely restricts the mines in the late production.Therefore,treatment of Da miao iron mine goaf is the urgent need.The nine goafs regions formed in the middle of the mine are aimed at the da miao iron mine,in this paper,according to the occurrence conditions of da miao iron ore production status and mined-out area commonly used at home and abroad,several kinds of goaf disposal scheme feasibility was analyzed,and finally determine open-pit stripping method is used to control.This paper uses the theory of three zones,Mathews stability diagram method,to evaluate the stability of mined-out area and classification,and uses the thick cross ratio method,the load transfer method of intersection line of nine minimum safe thickness of roof of mined-out area.The critical safety thickness is verified and adjusted by empirical analogy method.According to the analysis and calculation results,the detailed design of the stripping technical scheme of the goaf was carried out,and the order of the nine goaf is determined in combination with the storage conditions of goaf.The safety measures of the open air strip in detail are developed to ensure the safety of personnel and equipment during the management of goaf.Through open-pit stripping method and treatment of mined-out area,mine in thoroughly eliminate the underground mined-out area at the same time,and can be in the open air stripping process produced a certain amount of low grade ore,reducing the cost of mine goaf governance.