寺河煤矿2301(上)工作面沿空巷道无煤柱开采技术

Pillar-free mining technology for goaf roadway in 2301(upper)working face of Sihe Coal Mine

针对寺河煤矿孤岛煤柱工作面工程条件,根据关键层理论,对孤岛煤柱工作面开采上覆岩体破断结构特征进行分析,寺河煤矿在巷道掘进支护时,上覆岩体可能存在砌体梁或者伪砌体梁结构,该结构会影响巷道的稳定性,同时由于采用分层方法进行2次回采,煤柱两侧采空区上覆岩层破坏较为严重,由此提出U型钢+柔模墙体支护的窄小煤柱沿空掘巷方案和锚碹基本支护的零煤柱沿空送巷方案,通过对比,最终确定在寺河煤矿2301(上)工作面选用窄小煤柱沿空掘巷方案进行工程试验。试验结果表明,不仅解决了矿井掘进及低回收率问题,避免井下煤柱的应力集中,而且实现区段无煤柱开采,回收留设的40 m煤柱,增加了矿井的可采储量,利于矿区可持续发展。

In view of the engineering conditions of the isolated coal pillar working face in Sihe Coal Mine,based on the key layer theory,the characteristics of the fractured structure of the overlying rock mass during mining of the isolated coal pillar working face are analyzed.During tunnel excavation support in Sihe Coal Mine,there may be masonry beams or pseudo masonry beam structures in the overlying rock mass,which will affect the stability of the tunnel.Due to the use of layered methods for two rounds of mining,the overlying rock strata on both sides of the coal pillar goaf are severely damaged.A narrow coal pillar goaf excavation plan supported by U-shaped steel and flexible framework walls and a zero coal pillar goaf delivery plan supported by anchor arches are proposed.Through comparison,the narrow coal pillar goaf excavation plan is finally selected for engineering testing in the 2301(upper)working face of Sihe Coal Mine.The experimental results show that it not only solves the problems of mine excavation and low recovery rate,avoids stress concentration of coal pillars,but also realizes sectional coal pillar-free mining,recovers the retained 40 m coal pillar,and increases mining reserves,which is conducive to the sustainable development of mining area.