厚及特厚煤层群采动影响下覆岩运动特征探究

Study on the Characteristics of Overlying Strata Movement Under the Influence of Mining in Thick and Extra-Thick Coal Seams Group

以新疆硫磺沟煤矿(4-5)02工作面、(9-15)06工作面、(9-15)08工作面为研究对象,借助UDEC数值模拟软件及现场监测数据,探究厚及特厚煤层群开采过程中,煤层上覆岩层的运动特征及覆岩运动对下位煤层开采的影响。研究结果表明:覆岩运动在多层关键层控制作用的影响下呈现明显的“上弱下强”特点;关键层控制作用使得覆岩运动自下而上呈现明显的“低-中-高”渐次发展特征;上位煤层开采过程中上方坚硬砂岩不易发生断裂破坏,覆岩运动不完全,致使下位煤层开采过程中高、中位岩层将发生较大的断裂破坏,有较大的弹性能释放,对此应在上位煤层开采过程中,开展合理有效的顶板预裂等控制手段,避免下位煤层开采过程中有较大的能量释放。

Taking the(4-5)02 working face,(9-15)06 working face and(9-15)08 working face of Liuhuanggou coal mine in Xinjiang as the research object,with the help of UDEC numerical simulation software and field monitoring data,the characteristics of overlying strata movement and the influence of overlying strata movement on the mining of lower coal seam were explored in the mining process of thick and extra-thick coal seams group.The results show that the overlying strata movement presents obvious characteristics of“upper weak and lower strong”under the influence of multi-layer key strata control.The key strata control causes that the overlying strata movement show obvious“low-medium-high”gradual development characteristics from bottom to top.In the mining process of the upper coal seam,the upper hard sandstone is not easy to break and damage,and the overlying strata movement is not complete,resulting in a large fracture damage in the high and middle strata during the mining process of the lower coal seam,and there is a large elastic energy release.In this regard,reasonable and effective roof pre-splitting and other control methods should be carried out in the mining process of the upper coal seam to avoid large energy release in the mining process of the lower coal seam.