【摘要】 为了厘清滑坡影响下的层状岩体中的隧道变形破坏机理，以略阳南山隧道-滑坡体系为例，利用FLAC软件，采用强度折减法计算了滑坡稳定性的变化，并基于遍布节理模型计算了滑坡稳定性变化各阶段层状岩体隧道衬砌弯矩分布特征。结果表明:南山滑坡的整体稳定系数在前缘开挖前为1.25，开挖后为1.17，开挖后长持时降雨工况下为1.03，滑坡稳定性变化较大;受层状围岩各向异性特性的影响，隧道衬砌受力表现出更为明显的偏压，山侧墙中下部出现弯矩峰值，与墙体开裂的实际位置一致;隧道衬砌的最大弯矩初始为67.7 kN·m，前缘开挖后为70.0 kN·m，长持时降雨工况下为84.5 kN·m，说明隧道结构受力与滑坡的稳定性关系很大;层理特征对隧道弯矩影响明显，若层理为水平或垂直时，隧道各部位的弯矩均较小，弯矩分布较为对称，当层理倾角较陡(45°～75°)，顺坡向时山侧边墙的弯矩出现最大值，南山隧道滑坡体系中的层理产状刚好处于极为不利的情况，从而导致了隧道变形开裂。该研究可为类似隧道滑坡体系工程设计提供一定参考。更多还原

【Abstract】 To elucidate the deformation and failure mechanisms of tunnels in layered rock masses under landslide influence,the Lueyang Nanshan tunnel-landslide system was studied. FLAC software was employed,and the strength reduction method was used to calculate landslide stability variations. Based on the ubiquitous joint model,the bending moment distribution characteristics of the tunnel lining in the layered rock mass were calculated at different stages of landslide stability change. The results show that: The overall stability factor of the Nanshan landslide was 1. 25 before front excavation,1. 17 after excavation,and 1. 03 under prolonged rainfall conditions,indicating significant landslide stability changes; Anisotropic characteristics of layered rock induces pronounced eccentric compression in tunnel linings,with maximum bending moments occurring at mid-lower sections of mountain-side sidewalls,consistent with actual cracking patterns; The maximum bending moment of the tunnel lining was initially 67. 7 kN· m,increased to 70. 0 kN· m after front excavation,and reached 84. 5 k N· m under prolonged rainfall conditions,demonstrating that the structural forces on the tunnel are closely related to landslide stability; Bedding characteristics influence the tunnel bending moment significantly. When bedding is horizontal or vertical,the bending moments at various parts of the tunnel are relatively small and the distribution is more symmetrical. When the bedding dip angle is steep( 45° ～ 75°) and aligned with the slope direction,the maximum bending moment occurs in the mountain-side sidewall. The bedding orientation in the Nanshan tunnel-landslide system falls precisely within this extremely unfavorable range,resulting in tunnel deformation and cracking. These findings can provide a practical reference for the engineering design of similar tunnel-landslide systems.更多还原