Dongpang Mine, Jizhong Energy Group Co. , Ltd.

针对深部强动压软弱煤层沿空掘巷留设煤柱及其围岩支护系统极易发生大范围失稳破坏难题,以东庞矿深部水平沿空煤巷作为研究对象,采用理论分析方法获得了上覆基本顶岩层断裂线位置,明晰了煤柱尺寸与内、外应力场及极限平衡区宽度之间的数值关系;引入偏应力分析指标,模拟研究了不同煤柱宽度下的沿空掘巷围岩偏应力与塑性破坏场响应特征,确定了深部强动压软弱煤层沿空掘巷窄煤柱合理宽度为7m。基于7m煤柱宽度情况下,模拟研究了回采期间超前工作面不同位置处的巷道围岩偏应力及塑性区分布状态,确定了超前工作面单体支柱加强范围;得出了掘巷稳定后其顶板、实体煤及煤柱帮塑化程度与偏应力峰值带边界线位置;明确了沿空巷道煤柱侧是围岩控制的关键区,阐述了掘巷支护设计时需将锚索穿过围岩偏应力峰值带边界线于围岩深部较完整区内的围岩控制对策,提出了“巷帮非对称槽钢桁架锚索网+顶板槽钢桁架锚索联合点锚索+局部破碎区注浆改性+单体液压支柱超前支护”的围岩综合治理技术。工程实践表明,研究所确定的7m宽煤柱及围岩综合治理技术可有效控制围岩变形,保障深部强动压软弱煤层工作面的安全回采。

Aiming at the large-scale instability and damage caused by coal pillars and surrounding rock support systems of the gob-side entry driving surrounding rock in deep weak coal seams with strong dynamic pressure, the deep horizontal coal roadway of Dongpang Mine is taken as the research object to reveal its failure mechanism. Theoretical analysis method was used to obtain the location of the fault line of the overlying main roof strata, and the numerical relationship between the size of the coal pillar and the internal and external stress fields, as well as the width of the limit equilibrium zone, was clarified. By introducing the deviatoric stress analysis index, the response characteristics of the deviatoric stress and plastic failure field of the surrounding rock of the roadway under different coal pillar widths were studied. The reasonable width of the narrow coal pillar was determined to be meters. Based on the width of a m coal pillar, the distribution of deviatoric stress and plastic zone in the surrounding rock of the roadway at different positions of the advance working face during mining was simulated and studied, and the strengthening range of individual pillars in the working face was determined. The degree of plasticization of the roof, solid coal, and coal pillar walls after stable excavation, as well as the boundary line position of the peak stress zone are obtained. It was clarified that the coal pillar side of the gob - side entry driving is the key area for surrounding rock control. The control measures for surrounding rock when designing support was elaborated, which require the anchor cable to pass through the boundary line of the peak stress zone of the surrounding rock and be within the relatively complete elastic zone in the deep part of the surrounding rock. A comprehensive treatment technology for surrounding rock was proposed, comprising “asymmetric channel steel truss anchor cable network on the side of the roadway+roof channel steel truss anchor cable joint point anchor cable + local fracture zone grouting modification + single hydraulic support advanced support” . Engineering practice showed that the comprehensive treatment technology for the m coal pillar and surrounding rock support technology determined by the research can ensure the safe recovery of the working face in deep weak coal seam with strong dynamic pressure.

吕风.深部强动压软弱煤层沿空煤巷煤柱宽度及非对称控制研究[J].煤炭工程,2025,57(1):120-128.