大柳塔煤矿综采工作面压架冒顶机理研究
Study on mechanism of powered support jammed and roof falling in fully -mechanized coal mining face
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摘要: 针对大柳塔煤矿52304综采工作面在回撤阶段发生的压架冒顶事故,采用现场实测、数值模拟和理论分析对事故的原因和防治对策进行研究。研究结果表明:因受特殊回撤工艺的影响,沿垂直于工作面方向布置的调节巷导致煤体应力集中系数过大,引发工作面与调节巷交叉处发生大面积片帮,最终因端面距超过临界值引发端面冒顶。同时破断块体因失去啮合力而大幅回转切落导致压架,并进一步恶化顶板状况,造成52304工作面在支架支撑力足够的情况下仍发生严重压架冒顶事故。由此确定了相应的防治对策,通过采用加强调节巷围岩的支护、优化回撤巷道的布置和选择非来压时期挂网等措施来预防事故的发生,并得到了52303工作面安全回撤的验证。Abstract: Accoding to the powered support jammed and roofalling accidents ocured in the face equipment remove stage ofNo.52304tuly-mechanized coal mining face in Dlita Mine, aite measurement umercal sinmulaton and theoretical analysis were appied to studly on accident causes and the prevenion and control counermeasures. The study resuts showed that ue to the infuences by the specal remove technique,the adjustment gateway set along the perpendicula to the coal mining face direction would cause the coal stress concentration coficient too high .and would cause lage area spalling occure at the cros section betwee the coal mtning face and the adiustment gateway and fnally due to the face front distance over the critical value would cause the roo falling at the face front area.Meanwihile du to the mesing fore lost, the broken rock blocks would highy rotate and cause the powered suppor anmed.Thus the roof conition would be further worse and under the suport resistance insuficient of the powered suppor in No.52304coal mining face serious powered support jammed and roo falig acidents ocured still Thevefore the relevant prevention and control countemeasures were proposed,the enhanced surounding rock suppor inthe adjustment gateway,the optimized layout of th face equipment remove gateway,the mesh pavement selected at the strata not pressurized period and othe measures were appietothe prevent and conrolof heaident occurrence.The equipment safety remove from No.52303 coal mining face was verified.