论文部分内容阅读
岩溶区隧道因受岩溶发育程度、岩溶位置等影响,其围岩变形特征与一般隧道存在较大区别。以某岩溶隧道为工程背景,对隧道仰拱底部存在隐伏空腔的围岩变形进行现场监测研究,并运用有限差分软件进行仿真分析,现场监测和仿真分析所得围岩变形规律基本一致。研究结果表明:随着隧道施工接近并通过空腔顶部,隧道拱顶处围岩向下沉降,其值不断增大;边墙处围岩沿隧道径向收敛,其值变化较小;仰拱处围岩由最初的向上隆起,至隧道施工到空腔顶部时的向下沉降,且其下沉值不断增大。空腔周围围岩向空腔内收敛,其顶部沉降位移最大,侧部收敛位移次之,底部隆起位移最小。
Karst tunnel due to karst development, karst location, the deformation characteristics of the surrounding rock and the general tunnel there is a big difference. Taking a karst tunnel as the engineering background, the on-site monitoring research on the surrounding rock deformation with concealed cavity at the bottom of inverted tunnel is carried out, and the finite difference software is used for simulation analysis. The deformation and deformation of the surrounding rock obtained by on-site monitoring and simulation are basically the same. The results show that: as the tunnel construction approaches and passes through the top of the cavity, the surrounding rock of the tunnel vault settles downwards and increases in value; the surrounding rock at the wall converges radially along the tunnel and changes little in value; Surrounding rock uplift from the initial to the tunnel construction to the top of the cavity when the sink down, and its sinking value continues to increase. The surrounding rock around the cavity converges into the cavity, with the maximum settlement displacement at the top, the secondary convergence displacement followed by the bottom uplift displacement at the minimum.