中文摘要：

告成煤矿的主采二1煤层属典型“三软”厚煤层，回采工作面隅角和回风流中瓦斯体积分数超限的主要原因是采空区瓦斯涌出过多，采取顶板岩石钻孔的方法对采空区冒落带及冒落裂隙带的瓦斯进行抽放，降低了回采工作面隅角和回风流中的瓦斯体积分数。避免了采煤工作面隅角和回风流瓦斯体积分数超限，同时克服了工作面风速超限的问题．实践表明，顶板岩石钻孔抽放冒落带及冒落裂隙带的瓦斯，是解决“三软”厚煤层瓦斯超限的有效途径．

英文摘要：

二1 coal bed belongs to typical coal bed with Soft roof, Soft coal and Soft floor （3S） in Gaocheng coal mine. In stope corner and return airway, the prime reason of gas overrun is gob caving gas overmany out. Roof rock drilling pulls out gas at gob caving band and gob caving slit band, redules gas consistency In stope corner and return airway and avoids stope corner and return airway gas overrun, at the same time, the wind speed overrun is settled at stope. Practice shows that the gas pulling out of roof rock drilling at gob caving band and gob caving slit band is an effective way to work at settling 3S coal bed gas overrun.