综放孤岛工作面回采巷道窄煤柱合理留设

摘要

Surrounding rock of isolated island working face has a relatively higher degree of stress concentration that leads to the difficulties in roadway support.In-situ measurement data of ground stress in 30222 isolated island mining workface in Sanyuan Xiaochang Coal Mining Company was used to analyze the distribution of surrounding rock stress in isolated island mining face.It shows that isolated island working face carries the burden of adjacent working faces which leads to a rise of stress compared to normal working face.The mechanical model of main roof over the narrow coal pillar was established considering stress concentration of working face.The width of narrow coal pillar was calculated.Results shows that,the roadway deformation can be well controlled by a 6m width of narrow coal pillar accompanied with reasonable supporting technology.%以三元小常煤业30222孤岛工作面回采巷道为背景,结合地应力实测数据分析了孤岛工作面围岩应力分布特征.研究表明:由于孤岛工作面面分担采空侧覆岩荷重,其围岩中应力相对常规工作面增大.在考虑工作面应力集中的基础上,建立了窄煤柱上方基本顶力学模型,推导了窄煤柱留设宽度计算公式,确定了窄煤柱宽度.现场实践表明,30222工作面留设6m窄煤柱、采用合理的支护,巷道变形能够较好的控制.