Research Surrounding Rock Contral Technology Roadway Driving Along Goaf In Qipanjing

In recent years,the mining technology of the roadway along the goaf has been widely used in China.Compared with the traditional roadway driving along the gondola,it has the advantages of high energy efficiency,prolonged service life of the mine and good mining safety.There are many successful examples in domestic mining areas.There are four stages to go through the roadway along the gondola: the solid coal excavation stage,the welcome mining stage,the gondola excavation stage,and the working face recovery stage.The paper takes the chessboard well I010908 back to the wind as the research object,according to the actual geological conditions of the mine.Using theoretical analysis,FLAC3 d numerical simulation combined with comparative analysis and field industrial test to compare the surrounding rock conditions,the stability control of surrounding rock in the roadway along the I010908 return airway was studied.(1)Determine the surrounding rock of the I010908 return airway roadway by analyzing the space-time effect of the roadway along the goaf,the surrounding rock structure and stress state of the four mining stages and the large structural stability of the surrounding rock of the roadway along the goaf.The basic characteristics of the large structural key block are characterized by the fact that when the curved triangular block B is unstable,the thickness of the unstable block is the thickness of the basic top,and the touch condition of the block B is calculated.(2)I010908 returning to the wind tunnel to meet the conditions of the narrow coal pillars with different widths,and use the numerical simulation technology to narrow the width and horizontal and vertical stress field distribution of the coal pillars,the displacement field and the displacement of the surrounding rock of the roadway.The relationship of the peaks is simulated and then combined with the narrow coal pillar width calculated by the limit equilibrium theory.Determine the reasonable width of the narrow coal pillar is 5m.(3)Combining the geological conditions and the stress conditions of the surrounding rock of the roadway,according to the design principle of support,the theoretical calculation of the support parameters of the roadway along the goaf is carried out,and the numerical simulation is used to verify that the length of the top anchor of the roadway is 2400 mm.The length is 2400 mm,the spacing is 800mm×800mm,and the bolt pre-tightening force is 20 KN.The roadway support scheme was designed using this parameter.(4)On-site anchor dynamometer to carry out spot check on the anchoring force of the anchor bolt,use the MYC-18 dynamometer to observe the force of the anchor cable,and observe the displacement of the roof with the BY-3 type roof separation indicator.The pre-tightening force,force condition and displacement are all within a reasonable range,further determining the support plan is reasonable and effective,ensuring the safety and stability of mining and improving the comprehensive benefits of the mine.