近距离煤层上行开采被保护层回采巷道支护技术研究

Study on the Supporting Technology of the Protected Layer Mining Roadway in the upward Mining of Short Distance Coal Seam

淮北临涣煤矿7煤与下部9煤的煤层间距平均为28.5 m,属于近距离煤层,开采方式为上行开采,此时7煤作为被保护层,受到9煤开采影响,回采巷道可能存在围岩变形程度大,支护方式选取困难的问题。以被保护层7111工作面机巷为研究对象,进行支护技术研究。通过理论分析巷道变形与破坏机理后,针对不同巷道地段设计了3种支护方案,运用FLAC^(3D)软件模拟下煤层开采后被保护层回采巷道在3种支护方式下围岩应力分布特征和顶底板、两帮位移及塑性区范围。结合现场实测分析后,表明支护方案和参数设计比较合理,为上行开采回采巷道支护提供了有效的方法。

The average distance between coal seam 7 and coal seam 9 at the lower part of Huaibei Linhuan coal mine was 28.5 m,which belongs to a short-range coal seam,and the mining method was upward mining.At this time,coal seam 7,as a protected layer,was affected by the mining of coal seam 9.The mining roadway might have the problems of large surrounding rock deformation and difficult selection of supporting methods.Taking the machine roadway of 7111 working face in the protected layer as the research object,the supporting technology was studied.After theoretically analyzing the deformation and failure mechanism of roadway,three support schemes were designed for different roadway sections.FLAC^(3D) software was used to simulate the stress distribution characteristics of surrounding rock and the displacement of roof and floor,two sides and the range of plastic zone under the three support modes.Combined with the field measurement and analysis,it showed that the supporting scheme and parameter design were reasonable,which provided an effective method for the support of upward mining roadway.