Abstract:
Combined with practical engineering, four factors of stress distribution in the lower coal seam was analyzed and the stress distribution as well as surrounding rock destruction in different positions of roadway has been studied by FLAC
3D with strain softening model. The results showed that stress distribution of the lower seam was less affected by upper mining height and the depth of coal seams group, while greatly affected by the characters of the roof in the upper seam and the distance between the two coal seams. The stress concentration of the roadway in the stress diffusion area was low and the range of plastic distribution decreased, while the stress of the roadway located in high stress area concentrated strongly. The best layout of roadway in the lower seam is in the stress diffusion area under goaf, and the support strength of the roadway under coal pillar must be enhanced.