Study On Bolt Support Technology Of Thick Coal Seam Gateway In TashanThick Coal Seam Gateway In Tashan Coal Mine

In Tashan mine of Datong mining area,in the early stage of construction,the traditional low strength and low rigidity bolt support method is adopted in the roadway,which can not effectively play the bearing role of the surrounding rock of the roadway.After the high cost of support and maintenance,it does not achieve the purpose of effectively controlling the deformation of the surrounding rock of the roadway and ensuring the stability of the roadway.In view of this situation,the original support should be improved.In order to solve the problem of roadway support in thick coal seam in Tashan mine,this paper studies the roadway support in thick coal seam of carboniferous system in Tashan mine by field measurement,laboratory experiment,numerical simulation and theoretical analysis.Based on the full investigation of the project site,this paper selects the typical roadway in the mining roadway for drilling and coring,and carries out the laboratory rock mechanics property experiment;in the representative roadway section,carries on the surrounding rock drilling peep,grasps the roadway roof surrounding rock crushing degree and the crushing area depth and so on.The theoretical basis and characteristics of the existing tunnel support theory are summarized,and its applicability under different conditions is evaluated.The axial and radial restraint of a single bolt in preventing the deformation and failure of the surrounding rock and strengthening the surrounding rock are analyzed.Through the research on the bolt support of roadway side and roof,the theory of bolt action has a deeper qualitative understanding.The FLAC3 D numerical simulation method is used to study.Under the condition of zero original rock stress field,the length,diameter,number,row distance,pretension and angle of anchor bolt are quantitatively analyzed.The influence degree and effect of these supporting parameters,anchor cable and w-steel belt auxiliary support are intuitively understood.From the simulation,it canbe found that the influence of each parameter on the support is regular.In addition,the mine pressure of the roadway is also observed and analyzed.According to the analysis of the surrounding rock geological conditions of the mining roadway,the roadway support mode is designed,and the bolt support mode is adopted as the main support mode,supplemented by other support modes.According to the specific geological data,the support parameters of anchor bolt,such as diameter,length and row spacing,are calculated.At the same time,other auxiliary support methods are also studied.After determining the support scheme of the roadway,the mine pressure monitoring is carried out to test the actual effect of the designed and adopted scheme.Through the field industrial verification of the final supporting scheme,it is concluded that the supporting scheme has obvious effect,feasible technology,reasonable economy and guiding significance for engineering practice.The improvement of the support technology improves the overall stability of the surrounding rock and the bearing capacity of the surrounding rock.Compared with the ordinary anchor mesh support,it has strong adaptability,better improves the support environment of the surrounding rock,is conducive to further reducing the support cost,and accumulates experience for the development of the group bolt support technology.At the same time,Shanxi Province also has similar conditions of coal mines,the total length of coal seam roadways is huge every year,using the technology in the paper can improve the level of support safety,and then drive the national coal industry roadways to improve the level of support safety,which has broad application prospects.