浅埋深特厚煤层小煤柱沿空掘巷强力支护技术研究

Study on Supporting Technology of Gob-side Roadway with Small Coal Pillar at Shallow Buried Depth Extra Thick Coal Seam

根据千树塔煤矿浅埋深特厚煤层地质条件,采用数值模拟并结合工程类比的方法,分析确定该煤矿沿空掘巷护巷煤柱宽度为8 m。提出了千树塔煤矿小煤柱沿空掘巷护巷的基本支护思路:保证围岩整体有足够的支护强度和刚度;薄弱部位进行重点控制;遵循控制效果与经济成本的合理平衡原则。提出了千树塔煤矿小煤柱沿空掘巷护巷高预应力强力支护技术方案并进行了现场实践,结果表明:运输巷道掘进期间围岩整体变形量在100 mm以内;工作面回采期间围岩最大变形部位为煤柱侧帮,最大位移量约为295 mm。实现了巷道掘进和工作面回采期间运输巷围岩的稳定与安全。

According to the geological conditions of the shallow buried depth extra thick coal seam in Qianshuta Coal Mine,numerical simulation and engineering analogy method were used to determine that the coal pillar size of gob-side roadway was 8 m.The basic supporting idea of the small coal pillar of gob-side roadway in Qianshuta Coal Mine was proposed:the whole surrounding rock should be guaranteed to have sufficient support strength and rigidity;the weak parts need focus control measures;following the principle that control effect and economic cost should be reasonably balanced.The technical scheme of high prestress and strong support for small coal pillars in gob-side roadway of Qianshuta Coal Mine was put forward and the field practice was carried out.The results show that the total deformation of surrounding rock during roadway excavation is within 100 mm;the maximum deformation of surrounding rock is lateral wall of coal pillar and the maximum displacement is about 295 mm during stoping,the stability and safety during roadway excavation and mining are realized.