Determination on Reasonable Coal Pillar Width for Pressure Relief and Outburst Elimination in Roadway Driving Along Next Gob

In order to lay out the outburst seam roadway in the stress-relaxed zone and realize fast driving,by taking Shengyuan Coal Mine as an example,based on the analysis of the distribution rule of the supporting stress and gas pressure on the gob side and through the numerical simulation and the field investigation of outburst hazard,a reasonable width of coal pillar for pressure relief and outburst elimination was determined.The results showed that there was an elastic zone inside 5 m-wide coal pillar,which could maintain a certain bearing capacity,and the deformation of the roadway surrounding rock was small.A 5 m-wide coal pillar reserved for roadway driving along the gob was just in the range of pressure relief and outburst elimination,the measured cuttings gas analytical indicators were all below the critical values,the gas emission volume was below 1.58 m³/min during driving,no outstanding dynamic phenomena appeared and the safe and efficient driving was thus achieved.