Roadway Stability Analysis of Different Positions Below Goaf and Coal Pillars

Taking No.9 seam in No.2 mining area and overlying No.8 coal seam area of Jialequan Coal Mine as the research background, we research the influence of overlying coal seam goaf and coal pillar on lower coal seam roadway. We use finite element software FLAC^3D to analyze the stress distribution, yield damage range and stability around the lower coal seam roadway and overlying coal seam goaf when the relative horizontal and vertical position of coal pillar is different. The research shows that the zone located under the goaf is stress decreasing area and the stress increases with the increase of vertical distance from goaf. The zone located under the coal pillar is stress increasing area and the stress decreases with the increase of depth in a certain range. The roadway should be arranged in stress decreasing area of goaf and should be more than 7 m from the pillar. In the case of a special area, the support should be strengthened.