论文部分内容阅读
针对粤东丘陵区某超大断面隧道进口段围岩较软弱破碎、处理不当极易坍塌的问题,为确保工程在该不良地质条件下顺利施工,采用FLAC3D数值软件对超大断面隧道软弱破碎围岩开挖进行数值模拟,通过对比分析双侧壁导坑开挖法和三台阶开挖法对围岩变形、塑性区分布的影响程度,寻找出最适合该隧道Ⅴ级软质破碎围岩段的经济、快速施工方法。将现场监测的围岩变形数据与数值仿真计算结果进行对比表明,三台阶开挖法可以更有效地控制超大断面隧道软弱围岩变形,适合于超大断面隧道软弱破碎围岩段的快速施工。
Aiming at the problem that the surrounding rock of the entrance section of a super-large section tunnel in the hilly area of Guangdong Province is relatively weak and fragile, it is easy to collapse due to improper handling. To ensure the smooth construction of the project under the adverse geological conditions, FLAC3D numerical software is used to simulate the weak broken wall rock Digging for numerical simulation. Through comparative analysis of the influence of the double-wall pilot excavation method and the three-step excavation method on the deformation and plastic zone distribution of the surrounding rock, the economy most suitable for Grade V soft crushed surrounding rock is found out Fast construction method. Comparing the deformation data of onsite monitoring with the numerical simulation results, it shows that the threestep excavation method can control the deformation of weak surrounding rock in superlarge crosssection tunnel more effectively and is suitable for the rapid construction of weak and broken surrounding rock.