Opencast And Underground Synergetic Mining In Dagushan Iron Mine

Dagushan iron mine is a large size deep open pit mine.At present,the open pit mining goes to the end.With the mining depth increasing,transport cost of ores and stripping ratio become larger.Owing to the going down of ores price,mine economic effect is unsatisfactory,it should be paid attention to low produce cost and improve mine effective,to guarantee sustainable development of Dagushan iron mine.In this thesis,a new mine method-open pit mining with underground minging present by Northeastern University was applied into Dagushan iron mine.Considering mine geological condition and mine drawing,3-dimensional model was constructed with SURPAC software,making the Space position relationship of dew mine state,ore bodies,faults,clip stone and surrounding and space form visualized.Moreover,a detail optimization to open pit mine boundary was made with the model set up,which made east working slope final boundary translation to west.The strip ratio of east working slope is larger.Making open pit ores quantity with large strip ratio transferred into hanging wall ore,adopting induced mining method.Meanwile,Xiaogushan open-pit mining area carried on a timely independent deep mining,and reduce the Dagushan mining area part of the stripping rock volume convergence.Third,the surface of the open at a timely steep minging leaving the mining induced caving method mining.Fourth,according to the open pit and underground cooperative exploitation,it was required that an adjustment to the open transport routes,which transformed the original design of the open cycle type transportation line change for west slope to the northwest side of reentrant type transport routes,preparing space for the mining of east wall;In addition,a collaborative arrangement development system of extended open pit mining and hanging wall ore underground mining was made.Digging adit was made from open-pit transport steps to hanging wall mine,forming a haulage system of hanging wall mine,to speed up the mining process of hanging wall ore,and realize a synergistic growth of production capacity.Fifth,using steep open pit for mining and underground induced fall technology,combined with the condition of Dagushan Iron Mine,construction of the excavator loading-the small truck transport-and cross mining in discharge process combining open-air steep help deepening mining scheme,the hanging wall structure parameters of mine induced caving,mining scheme,and use of underground goaf volume control rock slope movement direction,so that it points to the collapse pit and does not fall in the open mining field,thus forming the Dagushan open pit iron mine underground cooperative exploitation scheme.Analysis shows that the proposed scheme of open pit and underground cooperative exploitation,can be highly adapted to the conditions of Dagushan Iron Mine.Because the open-air stope decrease stripping rock volume and hanging wall ore save off the mine engineering etc.,it can greatly reduce the production cost of ore and improve the mining efficiency,and realize the transition from open-pit to underground smooth transition and increase cohesion.