关键词: 特厚煤层, 沿空掘巷, 小煤柱, 数值模拟

Abstract: Aiming at the present situation of roadway protection effect of wide coal pillar, large deformation of coal wall wall and surrounding rock, and serious waste of coal resources when driving along goaf in fully mechanized caving of extra-thick coal seam, etc. Taking 2302 working face track passage of Panjin Coal Mine in Yili as engineering background, a mechanical model of narrow coal pillar was established based on limit equilibrium theory, and the influence laws of lateral pressure coefficient, mining height, buried depth and support resistance of coal pillar on the width of narrow coal pillar were investigated. The results show that the width of coal pillar increases with the increase of the first three pillars, and vice versa. The difference between the upper limit and lower limit of the reasonable width range of coal pillar also increases, while the latter hardly changes. In addition, combined with the geological conditions, the width of the narrow coal pillar is determined to be 6m, and its rationality is verified by numerical calculation, and the industrial test is carried out on the track passage of 2302 working face. The field practice results show that during the period of 6m narrow coal pillar excavation along the goaf, the roadway section development contour has no obvious deformation, and the surrounding rock control effect is remarkable.