Abstract: Highly-located drainage roadway along seam is an important method for controlling pressure-relief gas, whose extraction efficiency is largely influenced by its layout parameters. In order to reasonably determine the relationship between the above two factors, the evolution rule of cracks in roof rocks has been simulated in the mining process of working face 24202 of close-distance methane-rich seam group. Results have shown that the maximum separation fracture zones lie at the point 15 times of the mining height in the vertical direction, and that appropriate broken fissures are 35 m away from the mining boundary along seam, which is the best layout position for highly-located drainage roadway. Therefore, highly-located drainage roadway should be set in the return airway of working face 24202 and, 60 m toward the roof by the dip angle 40°, and 8 m along the seam. Field industrial experiments have indicated that the drainage radius of single highly-located drainage roadway is 55-60 m, 4-5 highly-located drainage roadways are in the active gas drainage period, and total effective drainage distance is about 500 m. In addition, the overall gas drainage amount of highly-located drainage roadway is 25.22 m 3 /min on average, which takes up 60.24% of the total gas drainage in quantity. In summary, high efficiency in controlling of pressure-relief gas was realized.

Key words: methane-rich seams group, highly-located drainage roadway along seam, gas enrichment zone, numerical simulation, pressure-relief gas drainage