Study on Layout of High Gas Extraction Roadway in Single Coal Seam

This paper took 2103 working face of Changcun Coal Mine as the engineering background, by analyzing of the stress state of the basic roof along the mining direction of coal seam, set up the mechanical model of the basic roof before the rock beam broke, and the periodic collapse step distance of the basic roof was solved; by using the collapse step distance, the permeability formula was introduced to rebuild the mechanical model and solve the distribution of internal permeability of rock girder, and the high level gas drainage roadway was arranged in the area with good gas permeability of coal seam according to the permeability classification standard. The boundary of shear failure zone was determined by establishing a two-dimensional model along the inclination direction of coal seam. The gas extraction roadway was arranged outside the shear failure zone through analysis. To sum up, the tunneling scheme was determined that the gas extraction roadway was arranged 27.03 m above the rail transport roadway and 29.82 m inner alternated with it.The actual measured gas drainage and the deformation characteristics of the roadway were given. The results showed that the location of the high gas drainage roadway is reasonable, which can ensure the safety production demand of coal mine.