层理发育硬煤层煤壁片帮机理及防治技术

Mechanism and Control Technology of Rib Spalling in Hard Coal Seam with Developed Beddings

为了分析层理发育硬煤层煤壁片帮机理,通过现场调研、试验室试验和理论分析的方法研究了煤体物理力学性质、节理裂隙分布对煤壁稳定性的影响,并提出了超高压注水防片帮技术。现场应用结果表明:横向层理发育硬煤层煤壁片帮发生在层理面,破坏形式以拉伸破坏为主;增大注水压力可增大硬煤湿润半径,缩短注水时间,增大注水孔距。应用过程中大块煤明显减少、开机率提高显著、煤壁片帮有效减缓,工作面推进速度得到提高。

In order to analyze the mechanism of rib spalling of hard coal seam with developed beddings,the site observation and theoretical analysis and laboratory experiment were applied to research the influence of rib stability of physical arid mechanical properties and joints and fissures distribution of coal.The control technology of rib spalling by water injection with ultra high pressure was proposed.The results showed that rib spalling of hard coal with transversely developed beddings often occurred on the bedding planes and the failure modes were dominated by tensile fracture.Increased water injection pressure could enlarge wetted radius of hard coal seam and shorten of water injec- tion time and enlarge the hole spacing.The application of this technology could reduce the occurrence of largesized coal obviously and im- prove the oDeratinz rate and effectively relieve the rib sDallinz and accelerate the advance speed.