The Numerical Simulation Of Pillar Recycling, Goaf Treatment And Pressure-relief Mining Scheme In A Mine

As mining continues with goes on,most mines have entered the deep mining stage.The shallow part often needs to recycle the pillar and the treatment of the goaf.Otherwise,the roof rock burst may be induced.Secondly,with the depth of mining increasing,the support pressure increase rapidly,mine impact ground pressure,roadway surrounding rock deformation and other disasters are increasingly appearing,which will seriously affect the safety and efficiency of deep resources mining.Based on the background of a certain mine,this paper puts forward the scheme of pillar recovery,goaf treatment and pressure relief mining.The main contents and conclusions are as follows:?1?Through the underground investigation,the indoor rock physical and mechanical test,combined with the underground pressure,the orthogonal numerical simulation inversion analysis is used to determine the reduction coefficient of the rock physical and mechanical parameters,and the rock mechanics parameters of the mine are obtained.?2?Combined with the current situation of the ground pressure and the distribution of the upper goaf,the joint scheme of the goaf treatment and pressure relief mining is put forward,and the construction parameters of the scheme are determined with the help of the Flac^3Dnumerical simulation.The horizontal distance from the outer pressure unloading construction roadway to the edge of the goaf is 25 m,and the depth of the excavation of the floor blasting is not less than 20 m,and the blasting should be fully loosened.?3?The numerical simulation shows that the first layer of the pillars and those below the 1010 m level wouldn't get collapsed and the phyllite on the hanging wall may merely get to collapse locally due to the prolonging fatigue damage in the pillar separation and extraction process.Furthermore,it would be possible to get rid of the mining ore depletion by the prolonging exposure and caving on the roof of the goaf by speeding up the mining process.And the separating rib pillar recycle between the two adjacent goaf areas,the pillar extraction should not be beyond half of the total.otherwise,the recovery of adjacent stope pillar,the partition column will collapse,resulting in reclaimed mined out area of mixed waste rock adjacent stope.?4?The numerical simulation shows that the pressure relief mining pressure relief mining,namely the V-shaped loosening blast and the partition mining on the bottom plate of the hanging tunnel,can just psrtly reduce the stress degree at the 910 m level,which helps to eliminate the stress condition of the rock burst basically at the level of910 m.when the extended separation pillar and the pressure relief mining process going on to the two adjacent goafs at the 960 m level have been filled with the cracked phyllite on the hanging wall with residual pillars in the stope favorable to get rid of the hidden risk.The technical proposal proposed above provides theoretical basis and technical support for pillar recovery,goaf treatment and pressure relief mining in the mine,which is also useful for other similar mines.