无煤柱沿空掘巷技术在永夏矿区的应用

Application of gob-side entry driving technology without coal pillar in Yongxia mining area

针对永夏矿区城郊煤矿十四辅助采区轨道巷完全沿空掘进围岩控制问题,分析了无煤柱沿空掘巷在资源采出率、围岩应力环境、施工效率等方面的优越性。通过建立完全沿空掘巷围岩力学模型,较为详细的分析了中厚煤层无煤柱沿空掘巷围岩应力分布规律、上覆岩层的赋存状态,总结了完全沿空掘巷围岩的变形特征,并提出无煤柱完全沿空掘巷围岩控制需要解决的关键问题。有针对性地制定了围岩控制方案,顶板采用"锚网梯+锚索补强"、沿空侧帮部通过"留设薄煤皮+打设29U型钢棚柱"、实体煤侧帮部采用"锚网帯+锚索补强"的联合支护技术方案。现场施工后设置矿压观测站,对无煤柱沿空掘巷围岩控制技术实施效果进行了跟踪监测。观测结果显示,巷道施工后顶板离层量及顶帮变形量较留设煤柱施工大幅减少,验证了技术方案的有效性。

In order to control the surrounding rock in the tunnel excavation of the 14 th auxiliary mining area in Chengjiao Coal Mine of Yongxia mining area,the superiority of non-coal pillar roadway excavation in resource extraction rate,surrounding rock stress environment and construction efficiency was analyzed. By establishing a full-empty roadway rock mechanics model,the stress distribution law of surrounding rock and the occurrence state of overlying strata were studied in detail in the mid-thick coal seams without coal pillars,and the roadway surrounding the roadway was concluded. The deformation characteristics,and put forward the key issues that need to be solved to control the surrounding rock of the roadway without pillars. The surrounding rock control plan was formulated in a targeted manner. The top plate adopts ＂ anchor net ladder ＋ anchor cable reinforcement＂,along the air side side through ＂ leave thin coal ＋ set29 U steel shed column＂,solid coal side the joint support technology scheme of ＂ anchor network ＋ anchor reinforcement＂ is adopted.After the on-site construction,the mine pressure observation station was set up to track and monitor the implementation effect of the surrounding rock control technology of the roadway without coal pillars. The observation results show that the amount of roof separation and roof deformation after roadway construction is significantly reduced compared with the construction of pillars,which verifies the effectiveness of the technical plan.