Abstract：Based on the briquette specimens of the outburst coal seam #7 of typical coal and gas outburst mine of Datong a mine of Songzao Coal and Electricity Co.，Ltd.，the experiment of outburst coal¢s gas seepage was carried out under fixed axial and confining pressures but changeable gas pressure by a self-developed triaxial permeameter. The experimental results are as follows. The gas seepage velocity of outburst coal samples increase with the increase of gas pressure under fixed axial and confining pressures. And the relationship between gas seepage velocity of outburst coal samples and gas pressure can be described as power function. The increasing rates of pressure gradient of two sides of outburst coal decrease with the increase of gas pressure and reach to zero at last. The increasing rate of the gas seepage velocity of outburst coal samples was decreasing with the increase of gas pressure and reaches to a constant value at last. The experimental results are of great significance in improving the efficiency of gas extraction.
