多重应力下小煤柱巷道矿压分析及治理研究

Analysis and Control of Mine Pressure in Small Coal Pillar Roadways under Multiple Stresses

为解决上覆区段煤柱应力、同层采空区侧向应力和工作面回采动压多重应力下的厚煤层小煤柱巷道矿压治理问题,以中煤塔山煤矿3-5#煤层30515综放工作面为工程背景,运用数值模拟和现场综合监测方法,揭示了小煤柱巷道应力分布规律,以及受采动应力影响下的巷道围岩破坏特征;基于此确定了“煤炮”预警机制、大直径钻孔卸压、锚索支护参数优化和“堆柱”支护等综合矿压治理措施。现场实践表明,通过采取积极的矿压治理措施,巷道帮部围岩变形量控制在0.7 m以内,顶部围岩变形量控制在0.28 m以内,有效地保证了小煤柱巷道掘进和回采期间巷道的稳定性,实现了工作面安全生产,最大限度地提高了采区回采率,提高了经济效益。

Ground pressure control in small coal pillar roadways of thick coal seams under multiple stresses involves the coal pillar stress in the overlying section, the lateral stress in the goaf of the same layer, and the dynamic pressure induced by mining. Taking the 30515 fully mechanized caving face of the 3-5 coal seam of China Coal Tashan Mine as the engineering background, this paper reveals the stress distribution and failure characteristics of surrounding rock under the influence of mining stress by numerical simulation and on-site comprehensive monitoring methods. This determined some comprehensive control measures, including the early warning mechanism of the “coal cannon”, the pressure relief of large diameter boreholes, the supporting parameter optimization for anchor cable, and the “pillar column” supporting. Field practice showed that, through active mine pressure control, the deformation of the surrounding rock of the roadway sides and roofs was controlled within 0.7 m and 0.28 m, respectively, which effectively ensured the stability of the small coal pillar roadway during the excavation and mining, realized the safe production, maximized the recovery rate and improved the economic benefits.