极近距离老空区下综采工作面撤面技术研究与应用

Research and Application of Face Removal Technology in Fully Mechanized Mining Face under Condition of Extremely Close Mined-out Area

为解决内蒙古上海庙矿区长城二矿1301N工作面浅埋极近距离老空区下开采撤面支护的难题,采取了煤机自割回撤通道,提前下卧工作面层位,托顶煤,人为增加顶板高度。采用以高预应力锚索+注浆+钢丝绳+抬棚为核心的支护技术。通过在支架顶梁超前铺金属菱形网、使用注浆锚索加固老空区破碎顶板、安设倾向钢丝绳实现整体柔性支护、每架敷设抬棚被动加固等施工方案,实现了回撤通道的支护安全。矿压观测表明,主动+被动支护,刚性+柔性支护的设计方案有效地控制了极近距离老空区下撤面切眼变形,保证了支架撤除期间的安全,实现了1个月完成工作面撤除,对同类型工作面撤除支护有一定指导意义。

In order to solve the problem of the withdrawal of work support in the 1301N working face of the Great Wall No.2 mine in Shanghaimiao mining area,Inner Mongolia,with shallow burying and extremely short distance goaf,the shearer self-mining channel was adopted,and the coal seam position of the working face was adjusted in advance to support the top coal mining.Increase the height of the roof artificially.It adopts the supporting technology with high prestressed anchor cable+grouting+steel wire rope+lifting shed as the core.The construction schemes such as laying metal diamond mesh in advance,using grouting anchor cables to reinforce the broken roof in the old goaf area,installing inclined wire ropes to achieve overall flexible support,and laying sheds for passive reinforcement of each frame,have realized the support safety of the withdrawal face.Observation of underground pressure shows that the design scheme of active+passive support,rigid+flexible support effectively controls the deformation of the roadway withdrawing from the mined-out area at a very close distance,and ensures the safety during the support removal period,which has been realized for one month.The completion of the removal of the working face has certain guiding significance for the removal of the support of the same type of working face.