Abstract: New Liangfengya tunnel on ChongqingGuiyang railway crosses closelydistributed K7, K8 and K9 coal seams. 3 gas discharging design options are studied by means of comparative analysis. In the end, option 1 of the gas discharging design, i.e., drilling discharging holes on the vertical tunnel face, implementing gas discharging for K8 and K9 coal seams in one operation before the gas discharging for K7 coal seam is performed, and the discharging holes being arranged in rectangular rows, is finally adopted, with the construction convenience, ventilation and lining stability considered. The adopted gas discharging design is suitable for the gas discharging of closelydistributed inclined coal seams prone to outburst. 

Key words: New Liangfengya tunnel, inclined coal seam, gas outburst, gas discharge, ventilation system