动压煤巷三维支护围岩稳定性分析

Analysis of the stability of surrounding rock by using three-dimensional support in coal roadway with mining-induced pressure

在探讨三维锚索作用机理的基础上,利用非线性离散元软件UDEC模拟了巷道在锚网支护、锚网索支护、三维支护等3种支护条件下围岩的变形及应力分布特征。模拟结果显示,高应力动压巷道采用三维支护时,顶板下沉量和两帮移近量分别为116.4、251.3 mm,比采用锚网索支护减少了17.9%和8.1%,这说明三维支护不仅在控制顶板下沉量方面非常优越,且能很好地控制两帮移近量;同时三维支护提高了顶板的水平压应力,使巷道围岩应力得到明显的改善,有效地阻止了巷道围岩的变形。

Surrounding rock control of dynamic coal roadway is one key technique to mine effectively and safely. Under three different supporting conditions of bolt, bolt and anchor, and three dimensional anchor rope, based on the action mechanism of three-dimensional anchor cable, this paper simulated stress and distortion characteristics of the surrounding rock of a roadway cross section by using nonlinear discrete element software UDEC. The simulation results show that the roof subsidence and the quantity of two walls＇ moving are 116. 4 mm, 251.3 mm when bolt and three-dimensional anchor supporting is used, which are reduced by 17. 9% and 8. 1% compared with bolt and anchor supporting. This indicates that three-dimensional anchor rope supporting not only possesses advantage in controlling roof subsidence but also is effective in the controlling of the two walls＇ moving. At the same time, three-dimensional supporting can enhance horizontal compression of roof, largely improve the stress of roadway surrounding, and effectively prevent the distortion of surrounding rock.