Study on the reasonable width of section coal pillar byusing FLAC^3D numerical simulation

This paper based on the actual mining conditions of No.6 coal seam of Hebei mine, internal stress and displacement distribution of coal pillar, the relationships between the coal pillar width and the stability of roadway surrounding rock were analyzed when adopt different coal pillar width schemes by using FLAC^3D numerical simulation, which obtained the width range of reasonable coal pillar should be set between the working faces,on the basis, combining with the actual situation of the mine and carrying on comprehensive consideration, the scheme of leaving 6 m coal pillar was determined, and then had carried on the industrial test, through the observation we found that the surrounding rock of roadway successively experienced no mining influence, mining influence and mining influence intense three phases, the surrounding rock of roadway within controllable range to meet the production requirements.comparing with adopt 15 m coal pillar scheme in accordance with the experiences which can reduce the loss of coal and increase the recovery rate, at the same time, the research of this paper has certain guidance and reference significance for the determining the width of coal pillar in the similar conditions of other mining areas.