In order to reveal the reason of the water-inrush disasters induced by the damage of surface gas drainage hole during mining of No.8101 working face in Wolonghu Coal Mine,by the way of theoretical analysis and field measurement,this paper comprehensively analyzed the movement characteristics of key stratum,the structure of gas drainage hole as well as the water inflow of No.8101 working face and the borehole TV,and so on.Results showed that the breakage of thick and hard key stratum resulted in the movement of overlying strata it controls,which caused tensile failure of casing outside the borehole in several sections,thus,the gas drainage boreholes became main channels that interconnected the K3 sandstone aquifer with water-flowing fracture zone below.All this has caused the sustainably large amount of water inflow on No.8101 working face.To ensure the surface gas drainage hole not to be damaged,it should be considered in three stages:pre-mining design,drilling construction and mining control.Meanwhile,relevant countermeasures should be carried out,including damage prediction in advance,strengthening the boreholes,and decreasing the damage by adopting harmonic mining,so as to realize the long-term stability of the gas drainage boreholes.%为揭示卧龙湖煤矿8101工作面地面瓦斯抽采钻孔受采动影响后破坏引发突水事故的原因,采用理论分析、工程实测手段对覆岩关键层运动特征、抽采钻孔结构、工作面涌水量、钻孔破坏窥视等信息进行了综合分析.结果表明,厚硬关键层破断后其所控制的大范围岩层整体运动造成钻孔套管多段拉伸破坏,抽采钻孔成为直接沟通K3砂岩含水层与下部导水断裂带的主通道,是引发8101工作面持续大量突水的主要原因.地面瓦斯抽采钻孔破坏防护应从采前设计、钻孔施工、采动控制三阶段考虑,采取采前损害预判、钻孔强化防护、采动协调减损的措施,以实现抽采钻孔的长期稳定.
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