上行开采工作面顺槽支护方案及实践

The practice of roadway supporting scheme in upward mining face

象山矿南二上山采区采用上行开采,3#煤层与下部5#煤层间距17~26 m,21305工作面位于5#煤层采空区顶板强裂隙带内,煤层及顶底板破碎,开掘巷道具有一定的风险。为了确定21305工作面顺槽的合理位置和支护方案,在明确工作面工程背景后,预判了裂隙带内3#煤层及顶底板完整性及开采可行性;分析确定了顺槽的合理位置,最终确定了顺槽合理支护方案,并对巷道掘进期间的问题及维护进行了介绍。分析认为,下部煤层开采后对上煤层破坏影响程度较小,上部3#煤层可进行正常掘进;设计21305工作面顺槽内错10 m,位于悬伸段内10~14.4 m处,此处3#煤层及顶底板比较完整,巷道稳定性较好,适合布置顺槽;顺槽采用该支护方式后,巷道掘进期间顶板无安全事故,但在后期掘进期间需加强顶板矿压观测,当围岩条件发生变化时,需及时调整支护参数以确保工作面顶板支护的安全可靠。

The distance between the No.3 coal seam and the lower No.5 coal seam is 17~26 m in the Nan’er Shangshan mining area of Xiangshan mine,and the upward mining is adopted.Because the No.21305 working face is located in the strong fracture zone of the gob roof of No.5 coal seam,the coal seam and the roof and floor are broken,there is a certain risk in roadway excavating.According to the mine geological conditions,the integrity of the No.3 coal seam and the roof and floor in the fracture zone and the mining feasibility were analyzed,the reasonable position and supporting scheme of the mining roadway were determined,and the safety measure during the tunnel excavation was put forward.The analysis shows that the lower coal seam mining has little influence on the upper coal seam,and the upper No.3 coal seam can be mined normally.The mining roadway of No.21305 working face is staggered by 10m,where the No.3 coal seam and roof and floor are relatively complete,so it is suitable for arranging mining roadway.The practice shows that there is no safety accident during the tunneling,but the roof pressure observation should be strengthened during the later tunneling.When the surrounding rock conditions change,the support parameters should be adjusted in time to ensure the safety and reliability of the roof support in the working face.