裂隙带顶板巷道围岩破坏机理及稳定性控制

针对上行开采过程中顶板巷道支护困难的问题,采用UDEC离散元数值模拟软件对上行开采过程中采场采动裂隙、塑性区以及巷道围岩裂隙、塑性区发育进行了系统的研究和分析,研究结果表明:采动作用下顶板巷道围岩破坏以巷道顶、底板破坏最为明显,靠工作面侧的巷帮破坏次之。采场采动裂隙、塑性区发育与巷道围岩裂隙、塑性区发育在工作面的推进过程中不断相互吸引和促进,最终贯通。同时,当采动作用达到一定程度时,采动裂隙会以顶板巷道顶板为起点向上发育,而巷道肩角处塑性区向上产生畸形发展,其发育方向与采场覆岩断裂角一致,其发育高度远远大于未受采动影响的巷道塑性区发育高度。基于分析结果,提出了上行开采裂隙带顶板巷道支护策略,并以山脚树矿上行开采为工程背景对其顶板巷道原有的支护形式进行了改进,改进后的支护能够有效保证巷道围岩稳定。以上研究成果可为上行开采工程中顶板巷道的支护提供设计参考,丰富采动巷道围岩稳定性控制理论成果。

Failure mechanism and stability control of roof roadway in fractured zone

In view of the support difficulty of the roof roadway in ascending mining，this paper conducted a systematic research on the mining-induced fissure，the cracks of roadway surrounding rock，the plastic zone of the overlying strata and the plastic zone of roadway surrounding rock.The research results show that with the influence of mining，the damage of roof and floor is the main failure of roof roadway，the damage of the roadway side closer to the working face is another factor.The fissure and plastic zone of overlying strata interact with the fissure and plastic zone of roadway surrounding rock，and finally they are interconnected.Meanwhile，when the mining influence reaches to a certain level，the mining-induced fissures developed upward start with the roadway roof，and the plastic zone of the shoulder of roadway lopsided development upward，its development direction is same to the breaking angle of overlying strata，and its developing height is far greater than the plastic zone of the roadway which isn’t affected by mining.According to the research results，the support principle of roof roadway in ascending mining has been discussed.Based on the discussion result，and with the engineering background of ascending mining in a south mine，the melioration has been made for its original support，and the ameliorated support can maintain the stability of roadway surrounding rock.The above research has provided a reference to the support of roof roadway in ascending mining，and enriched the theory about the control of surround rock stability of the mining induced roadway.