| The type of the tungsten deposit is a typical medium-high temperature hydrothermal quartz fine vein belt after the magmatic period.The deposits of this type of mineralization model have the obvious characteristics: in the horizontal direction,generally one or more groups of parallel steeply inclined veins occurrence of morphology,between thin ore veins are interlayers(walls)of varying thickness;in the vertical direction,the occurrence of ore body changes significantly,thickness and morphology are diverse,with the depth of the upper veins The zone transitions to the fine vein-large vein mixed zone,the pulse interval becomes larger,and the reasonable mining method also transitions from strip mining to combined mining.The shallow hole retention method will be replaced by a new mining method suitable for combined mining.The paper takes the combined mining of fine veins and large veins in the transition period as the starting point,selects the above-mentioned typical ore bodies of a tungsten mine as the engineering background,and refers to and analyzes the actual production of the mine.Field surveys,indoor tests,numerical simulations,and theories are used.Through analysis and other methods,the effective application of the high-segmentation ore house method in the steeply inclined thin vein group tungsten ore has been studied.The main research results are summarized as follows:(1)Oriented cores of surrounding rock at different depths in the mining area were drilled,and uniaxial compression tests and Brazilian split tests were performed on the rock samples to obtain basic mechanical parameters.During the test,the Kaiser effect of acoustic emission was used to carry out three-dimensional in-situ stress measurement of the rock,and the comprehensive method was used to identify Kaiser points to obtain in-situ stress data at different depths in the mining area.(2)Through fine modeling of fine vein zone ore bodies,the stress and displacement distribution characteristics of the upper fine vein zone ore bodies during the mining of the upper fine vein zone by the shallow hole retention method were simulated good.(3)Based on the requirements for the combined mining of the fine veins and large veins in the central part of the ore body,a high-segmentation phase mining method for the group veins and tungsten deposits was proposed.The numerical simulation software FLAC3 D was used to analyze the stability of surrounding rocks.The results of simulation analysis show that the surrounding rock can maintain self-stability during the mining process,and the method is easy to lose the thin sandwich wall between the mining veins,avoiding the risk of the thin sandwich wall failure.The new method considers the stability of the surrounding rock technically feasible.(4)Combine FLAC3 D numerical simulation technology and PCA-SVM machine learning method to carry out forward and reverse optimization of stope structure parameters.FLAC3 D was used to simulate the various parameter schemes and obtain the corresponding stability evaluation index values.The parameter-evaluation value was used as the PCA-SVM input data sample to establish the PCA-SVM structural parameter reverse prediction model.The high-stage mining method was obtained.The optimal structural parameters of the stope are: the length of the mine is 53 m,the width of the pillar is 2 m,and the height of the top pillar is 5 m.(5)Carry out experimental design of ore body mining and calculate technical indicators such as the loss and dilution rate of mining stope and production capacity.The results show that due to the combined mining and depletion rate increased by 10%,but the production capacity has greatly increased,and the annual output benefits of the new mining method The difference between the original method and the original method is 30 million yuan,which proves the technical and economic feasibility of the mining method in the high-stage stage. |
PDF Full Text Request