Huadian Coal Industry Group Co., Ltd.
Shenmu Longde Mining Co., Ltd.
Mining and Design Dept., Tiandi Science & Technology Co., Ltd.

针对隆德煤矿近距离煤层上下同采工作面巷道围岩稳定性控制问题,采用现场实测和理论分析方法,对多次采动影响下巷道支护体受力特征和煤柱应力演化特征进行研究。结果表明,巷道锚杆/索受力经历7个变化阶段,包括采动影响前初始稳定阶段、单工作面超前影响阶段、双工作面超前影响阶段、采动卸压区快速升高阶段、采动应力恢复区慢速升高阶段、二次稳定阶段和双工作面开采扰动升高阶段;煤柱采动应力演化经历5个阶段,包括采动影响前初始稳定阶段、单工作面超前影响区缓慢上升阶段、采动卸压区快速上升阶段、采空区压实自由演化阶段和双工作面开采扰动升高阶段。随着钻孔应力计安装深度增加,煤柱应力呈现先升高后降低趋势,煤柱浅部3m左右进入塑性状态,承载能力降低;基于上述观测结果,对新掘巷道支护参数进行优化,在保证围岩长期稳定性的同时还可以降低支护费用,实测结果表明,支护参数优化后巷道表面位移量在工程允许范围内,巷道围岩裂隙发育程度较低。

seam in close proximity of Longde Coal Mine. The roadway support forcing characteristics and coal pillar’ s stress evolvingcharacteristics under the influence of multiple mining are studied using on-site observation and theoretical analysis. The re-sults show that the bolt/ cable force of roadway undergoes 7 stages: the initial stable stage before the influence of mining, theadvanced influential stage of single working face, the advanced influential stage of double working faces, the rapid risingstage of mining pressure relief zone, the slow rising stage of mining stress recovery zone, the secondary stable stage and therising stage of mining disturbance. The evolution of the mining stress of coal pillar experiences five stages: the initial stablestage before the influence of mining, the slow rising stage of the advanced influence area of working face, the fast rising stageof the mining pressure relief area, the free evolution stage of the mined-out area compaction and the rising stage of miningdisturbance. With the increase of the installation depth ofthe borehole stress meter, the stress of the coal pillarincreased at first and then decreased. The shallow part ofthe coal pillar entered a plastic state at about 3 m, and thebearing capacity was reduced. Based on the above observation results, the support parameters of newly tunneling roadwaywere optimized to ensure the long-term stability of surrounding rock and reduce the support cost. The measured results showthat the roadway surface displacement was within the allowable range of the project, and the crack development degree of thesurrounding rock was low.

国家自然科学基金面上项目(51974160)