Research On Reasonable Mining Scheme For The Residual Ore In Chengchao Iron Mine

In the past,the rich mineral resources were excavated and the poor wereabandoned,so a lot of useful mineral resources were lost.With the increasing demandfor mineral resources and the selecting progress of technology,it demanded us to agreater extent to recycle the residual ore resources. The geological conditions of theresidule ore are complicated, we often encounter many difficulties in the process ofmining,at the same time whether it is feasible to excavate the residual mineralresources need further argument.The research topic of this paper is mainly to solvethe problem of the safety when recycling the residual ore in east area of Chengchaoiron mine,for the sake of the accuracy of the simulation results, we mainlycompleted the following works:Firstly, based on the engineering geological data which collected and the fieldmonitoring data of the earth’s surface,we use the unascertained measure theory toforecast the key monitoring data on the surface,and analyse the security factors;Secondly, according to the mining area,3D geological model is established, then weuse the finite difference software to do the numerical simulation and calculation, andthen analyse the the surface deformation,the situation of flood control dam, thecondition of the main mining area which are influenced by the excavation,so that wecan know the reasonable safety mining areas;Thirdly, by selecting the typical sectionas the research object, we adopt the finite element software of Ansys to calculate andanalysis, by analysing of the goaf roof stress, strain and safety coefficient in differentthickness of pillars,in order to identify reasonable thickness of safety pillar;Fourth,according to the possible influencial safety factors, and combine with the calculationresult of the numerical simulation, we can propose some safety prevention measuresand suggestions in the process of recycling ore.The results of this paper show that the flat-back cut and fill mining method isthe optimal scheme, the no.21residual orebody, the no.3orebody and the no.2 residual orebody on level-250m~160m an be excavated, the no.2residual orebodyon level-160m~-100m should be strictly excavated in accordance with therequirements, for the no.1orebody we suggest it can’t be excavated, at the same timeit should reserve10meters of the thick pillar,and the unascertained measure theory,the computer simulation and the actual situation is more consistent.The researchresults can be useful to some mines whcih also want to recycle the residual ore, andit also has some significance guide meaning to the safety recycling of ore inChengchao iron mine.