Research on strong strata behaviours mechanism and prevention technology of heading roadway in extra-thick coal seam

In order to ensure the safety of heading roadway in extra-thick coal seam, theoretical analysis, numerical simulation and field measurement were used, t he mechanical mechanism of large pressure and its appearance characteristic was reseached, and the practice of comprehensive management prevention were carried out.The results showed that concentrated pressure in the heading roadway was the main factor that caused the phenomenon of large strata pressure in the lower coal s eam under the influence of the upper coal pillar in contiguous seams mining. With the increase of the horizontal distance between the upper coal pillars and the heading roadway, the maximum drilling cuttings of coal seam of the roadway was decreased, and the ventilation roadway ( the horizontal distance between the upper coal pillar and roadway was 10 m) was 1. 2 times as much as transportation roadway ( the horizontal distance between the upper coal pillar and the roadway was 40 m) for it. Pra ctice showed that effective to take measures of coal seam pressure relief, strengthening support, optimizing design, strengthening monitoring and so on, safety control of rock stability of the heading roadway in coal seam could be realized under high pressure condition. It provided a reference for the prevention and control of strong str ata pressure of the heading roadway under the similar conditions.