Study On Roadway Support Technology Of Working Face In Residual Coal Mining Of Thick Seam

Coal is a non-renewable resource,in China's economic and social life plays an irreplaceable role.With the rapid exploitation of high-quality coal seams over the years,coal resources have been depleted,how to improve the recovery rate of coal mines naturally put on the study schedule.Thick coal seam on the stratified by the backward roadway mining method after mining,leaving a large number of high quality coal resources,resulting in coal mining rate is very low.The recovery of the resources of this part of the residual coal is of great significance to improve the recovery rate of coal mines.And the recovery of this part of the coal resources,the work of the roadway due to serious damage to the surrounding rock and more difficult to support than the general roadway.Therefore,it is of great practical significance to study the suitable supporting method under the condition of surrounding rock.In this paper,the special damage of roadway surrounding rock in the thickened coal mining face under the thick coal seam in Hufeng Coal Mine is studied by field investigation,theoretical analysis and numerical simulation.According to the characteristics of surrounding rock failure,And the stress state of the surrounding rock of the roadway is analyzed theoretically,and the support of the surrounding rock of the working face is designed rationally.Through the numerical simulation results,the optimal support mode is determined and Protection parameters:(1)when the top of the mining roadway before the old goaf is not broken: the use of I-beam support,spacing 700 mm;(2)when the mining roadway above the old goaf collapse,the use of short bolt + I-beam shed support:A,the top coal seam thickness of 1.2 m: anchor length of 1.0 m,spacing 900 mm × 900mm;I-beam shed spacing 700mm;B,the top coal seam thickness of 1.4 m,the anchor length of 1.2m,spacing 900 mm ×900 mm;I-beam shed spacing 700mm;C,the top coal seam thickness of 1.6m,the anchor length of 1.4m,spacing 900 mm ×900 mm;I bit steel shed spacing 700 mm;(3)When the excavation roadway above the coal pillar,for the long anchor + anchor cable + metal mesh support way,the top bolt length 2500 mm,spacing 900 mm × 900 mm;cable length 8200 mm,Is 1900 mm × 1500 mm.