特厚顶煤单双夹矸层巷道开挖围岩变形破坏特征研究

Study on Deformation and Failure Characteristics of Surrounding Rock during Roadway Excavation of Single and Double Gangway Layer with Extra Thick Top Coal

针对特厚顶煤巷道开挖掘进时,单双夹矸层巷道围岩变形破坏特征不明晰的问题,以山西某矿13103工作面进回风巷道为工程背景,运用数值模拟的方法对巷道开挖过程中围岩变形破坏特征进行研究。研究结果表明,应力集中于巷道顶角上部并呈椭圆状分布,顶板最大下沉量出现在巷道中部且随掘进长度呈指数增长;单夹矸层巷道相比双夹矸层巷道应力集中幅度更高,应变更大,顶板破碎更严重。通过对单夹矸层巷道部分锚杆锚索倾斜打设并加长锚索后巷道变形控制效果显著提升,围岩强度得到明显增强,能够保证巷道稳定。

Aiming at the problem that the deformation and failure characteristics of the surrounding rock in the single and double gangue layer roadway are not clear during the excavation of the extra thick top coal roadway,numer-ical simulation methods were used to study the deformation and failure characteristics of the surrounding rock during the excavation process taking intake and return air roadway in the working face in a certain mine in Shanxi Province as the engineering background.The research results show that stress is concentrated in the top corner of the roadway and distributed in the elliptical shape.The maximum subsidence of the roof occurs in the middle of the roadway and in-creases exponentially with the length of excavation;Compared to double gangue layered roadway,single gangue lay-ered roadway have higher stress concentration,greater stress changes,and more severe roof fragmentation.The de-formation control effect of the roadway is significantly improved after the single gangway layer roadway that the anchor rods and anchor cable inclined to play and lengthen the anchor cable,and the strength of the surrounding rock is sig-nificantly enhanced,which can ensure the stability of the roadway.