复杂下伏采空煤巷影响下软岩隧道开挖稳定性数值模拟

Numerical Stability Simulation of Soft Rock Tunnel Excavation under the Influence of Complex Underlying Goaf Coal Road

以牛峒山隧道工程为依托,运用有限差分数值模拟软件,研究了复杂下伏采空煤巷影响下隧道施工期间的稳定性。结果表明:采空煤巷的存在将导致新建隧道与既有采空煤巷对围岩的扰动区域相互重叠,造成隧道的失稳破坏;采空煤巷近接隧道的方式和距离均会影响隧道开挖期间的稳定性,采空煤巷与隧道的间距大于或等于5 m时,可认为隧道的稳定性较好;采空煤巷与隧道的间距较小时,隧道的稳定性随下伏采空煤巷倾角角度的增加而逐渐减弱。

Based on Niutongshan Tunnel engineering,a numerical simulation model of the tunnel crossing complex underground mined-coal roadway has been established by using finite difference numerical simulation software and the influence of goaf coal roadway on surrounding rock failure and lining structure deformation during tunnel excavation has been analyzed.The results show that the existence of the underlying goaf coal roadway will lead to the overlapping of the disturbed area of surrounding rock during tunnel construction and the instability and failure of the tunnel.The approach and distance of the mined-out coal roadway near the tunnel will affect the stability during the tunnel excavation.When the distance between the mined-out coal roadway and the tunnel is greater than or equal to 5 m,the stability of tunnel excavation can be considered to be good.When the spacing between the mining roadway and the tunnel is smaller,the stability of tunnel construction gradually decreases with the increase of the mining roadway inclination angle.