鹤煤五矿深部交岔点大断面软岩巷道支护对策研究

Supporting strategy for large span intersection in deep soft rock roadway of the Fifth Coal Mine of Hebei Coal Group

鹤煤五矿三水平轨道下山地处向斜轴部,构造应力大,且受到上部采空区强烈的开采扰动,巷道变形严重,生产接续十分紧张。通过对该巷道工程地质条件的综合分析和地质力学评估,研究了该巷道的变形破坏机理及变形力学机制,并针对新开巷道大断面交岔点提出了以底角锚杆控制底臌的锚网索+柔层桁架耦合支护方案,且对该方案主要技术环节进行了优化,并通过数值模拟和现场实施验证了方案优化的准确性和可靠性。实践证明:该方案可以充分发挥锚网索和桁架的耦合支护作用,最大限度地发挥围岩的自承能力,有效控制巷道变形,为矿井的安全高效生产创造了条件。

The third level deepening roadway of the Fifth Coal Mine of Hebi Coal group located in the syncline axis suffers from severe tunnel deformation and short supply of production due to high tectonic stress and strong disturbance of the upper working face.Based on comprehensive analysis and mechanical evaluation of the engineering geological conditions around the roadway,the mechanical mechanism of deformation and the failure of the roadway are studied.A new coupling supporting design,bolt-mesh-cable ＋ truss with anchor in floor to control floor heave,is proposed and relevant technology is optimized in accordance with the large span intersection of the new tunnel.The accuracy and reliability of the optimum design is proved by numerical simulation and in-situ monitoring.Practices have proved that the bolt-mesh-cable ＋ truss scheme will make full use of the action of coupling support sufficiently,and bring the self-supporting capability of adjacent rock into full play so as to control the roadway deformation effectively,and provide conditions for safe and efficient production of the mine.