Research On The Structural Parameters And Multi-layer Flow Law Of The Stope Below 1300m In Jianshan Iron Mine

The occurrence condition o f Jianshan mining area is complex,which is a deposit with mult iple rock interlayer inclined mult i-ore belt,and the ore body and interlayer in the mine belt are layered in each other,and the underground mining is applied to the sect ional caving method without pillar.In the process of mining,due to the difficult y o f interlayer removal,the mining control is difficult,affected by the mixing of the top overburden and stone,and the loss of ore is much more depleted.At present,for this kind o f ore body with interlayer at home and abroad,no effective method has been found in the application of ore loss dilut ion control in the process o f mining without pillar sect ional caving method.In this paper,the method of co mbining physical similarit y simulat ion experiment,theoretical analysis and numerical simulation is adopted to reduce the loss o f mult i-sandwich orebody in Jianshan mining area.Starting from the actual mining situat ion of mining area,this paper analyzes the reasons for the large dilut ion of ore loss in Jianshan mining area.Fro m the fo llo wing aspects to study:the determinat ion of bulk flow parameters,and draw out the shape of the release body,for the mining area parameter optimizat ion to provide a basis;The step size is opt imized in co mbination with the bulk flow parameters;Invest igate the law of the mixing of the stone in the process of ore-mining and the effect of the deplet ion of ore loss,and propose an effect ive scheme to improve the existing ore-mining control mode to reduce the deplet ion loss caused by the stone.Through the experiment of bulk flow parameters,the movement law of Ore rock at the end of the ore is studied,and the form of release body is determined according to the stochastic medium theory.the flow parameters of the ore bulk are obtained:?=1.9521;?=0.1272;?₁=1.5340;?₁=0.2183;k=0.2492.The optimum route spacing is calculated by 18m,and the reasonable mining step distance is 5.32⁶.67m,and the caving step distance is 3.8m⁴.7m.Through the numerical simulat ion experiment of mult i-sect ional ore discharge,it is determined that the opt imal discharge step distance of the vertical direction approach of Jianshan iron mine is 5.88m and the optimal disintegrat ing step distance is 4.2m.In the process,it is found that the use of low-depleted ore deposits in Jianshan Iron Mine is feasible,which can reduce the deplet ion rate of ore and increase the ore mining qualit y.By using PFC^{3 D} particle flow software,the flow law of caving bulk in mult i-sect ional mining process with multi-interlayer orebody is simulated by numerical simulat ion,and the flow law and mixing law o f interlayer bulk in caving rock are obtained,as well as the influence of interlayer on ore loss and dilution.Finally,co mbined with the conclusion of experimental research,it is reco mmended that Jianshan iron mine should adopt the control mode of the combinat ion of cutoff grade and total ore t ype for this kind of ore body with many interlayer.In the research content of this paper,the combination o f physical simulat ion ore mining experiment and PFC³ D D part icle flow so ftware numerical simulation is used to process the ore discharge data by using Origin software and Mat lab so ftware.Based on the flow law and mixing law of the sandwich bulk in the caving rock,the influence law of the stone clamp on the ore discharge is analyzed,and the corresponding control method is put forward.The research results provide a basis for so lving the problem o f large loss and dilution o f mult i-mezzanine orebody in Jianshan mining area.