Research On Mining Technology And Stope Structure Parameters Of Self-propelled Iron Ore By Segmented House Method

The ore body of zizou iron mine of Yunnan xinpinglu electric mining co.,ltd.is gently inclined?inclined?steeply inclined,thin?medium thick?thick,the ore is moderately stable,the surrounding rock of upper and lower plates is moderately stable,the geological grade is 38.85%,it belongs to medium and low grade difficult mining body,and it requires high ore dilution rate.the comprehensive geological grade(thin inclusion stone cannot be removed)is about 38%,the recovery grade is?35%,and the corresponding dilution rate must be controlled below 9%.because the ore body is complex and difficult to mine,the traditional mining method and technology are difficult to solve the problems of large ore loss and dilution,etc.it is urgent to research and develop new mining methods and technological parameters.Based on the research background of sublevel room method mining in the middle section of zizou iron mine from 1480 to 1430,through on-site engineering geological survey and indoor mechanical tests,combined with the actual situation of the mine,the stability analysis and optimization research of reasonable structural parameters of sublevel room method stope are carried out by combining theoretical analysis and numerical simulation.The physical model of the mine section was established by the finite element software ANSYS 15.0,and the model was converted to FLAC3D5.01through the interface for later excavation simulation.Firstly,the section height is optimized,and the excavation is carried out according to the 10m height of each step.The stope stability is simulated when the section(stage)height is 10,20,30,40 and60m,and the best section height is selected.After that,on the basis of the sectional height,the stoping simulation schemes with different pillar sizes and different room spans are designed,the changes of stope stress,displacement and molding area under different size parameters are studied,and the optimal ore block size is obtained through analysis.(1)According to the requirements of the processing department for ore grade and the technical and economic conditions of mining,new mining methods and processes such as sublevel room method are proposed.The stope structural parameters of sublevel room method are optimized by theoretical analysis and numerical simulation methods,and preliminary structural parameters are obtained.(2)FLAC^3Dis used to optimize the section height,and the excavation is carried out according to the height of 10m in each step.It is found that when the section height reaches 40m,a large number of tensile failure areas occur on the stope roof during the excavation process,and a through shear failure plastic zone appears on the column section,and the stope is in a stable state when the section is 30m.The minimum principal stress formed by stope excavation at different sectional heights does not exceed the tensile strength of rock mass.The vertical and lateral displacements of stope top and bottom plates and upper and lower plates are within the safe displacement range of stope.The sectional height is selected as 30m;through comprehensive analysis.(3)Optimize the structural parameters of the ore block,keep the top column 5m unchanged,simulate according to the spacing column 4m,5m and 6m,and the span of the ore room 15m,18m,21m and 24m,draw up 12 schemes to simulate,and comprehensively analyze and select the optimal structural parameters of the ore block as the top column 5m,spacing column 5m and span of the ore room 15m.On the basis of on-site engineering geological investigation and indoor mechanical experiments,the paper establishes the physical model of the mine section by ANSYS 15.0,and converts the model to FLAC^3D5.01 through the interface,studies and optimizes the stope stability and structural parameters of self-propelled iron mine sublevel room method,obtains reasonable stope structural parameters,and provides theoretical basis and reference for mine design and construction.