沿空掘巷小煤柱稳定性分析

文章采用数值计算软件FLAC3D,研究了不同煤柱宽度及锚杆支护强度对沿空留巷侧小煤柱稳定性及掘巷巷道围岩变形的影响,得出煤柱宽度是影响煤柱稳定性与巷道围岩变形的决定性因素,高系统支护强度能有效地控制巷道围岩变形的结论。同时,以朱集矿沿1111(1)工作面轨道平巷为工程背景,得出:煤柱宽度为3m时,煤柱内垂直应力集中系数低,应力集中影响范围小,煤柱与掘巷巷道变形量最小,稳定性最好。在此基础上确立的高强度锚杆支护方案,成功保持了小煤柱的稳定性并控制住掘巷阶段巷道围岩的大变形。

Analysis on Stability of Coal Pillar when Keeping Small Coal Pillar to Dig the Lane along the Gob-side Entry Retaining

Abstract: The stress distribution and the stability of the roadway surrounding rock is deferent from the typical gob-side entry driving when keeping small coal pillar to dig the lane along the gob-side entry retaining. It will benefit to the stability of the coal pillar and decrease the width of the coal pillar because of the high strength filling wall of the gob-side entry retaining works to support the roof of the goaf. In this paper numerical calculation software was used to research the stability of small coal pillar along the gob-side entry retaining and the effect on the deformation of the surrounding rock in driving tunnel with different width of coal pillar and different anchoring strength of rock bolts, a conclusion was drawn that the width of the coal pillar is the decisive factor which affects the stability of the coal pillar and the deformation of surrounding rock, and the high system support strength can control the deformation of surrounding rock efficiently. According to the engineering background of the 1111(1) working face’s track drift in ZhuJi coal mine, the vertical stress of the coal pillar is low with a small influence circle and the deformation of the coal pillar and the roadway, it’s stability is best of all when the coal pillar is 3m wide. The high strength bolt supporting scheme was determined based on that basis. The stability of coal pillar and the big driving tunnel deformation were successfully controlled.