软弱围岩隧道开挖方案优化研究

根据合福线合肥至福州段的万山隧道特点和隧道开挖施工现状,参考前期围岩变形、锚杆应力等监测成果,采用有限元方法分别模拟万山隧道Ⅴ级围岩六步CD法和三台阶七步法两种开挖方案,比较分析两种开挖方案下洞室应力、变形的数值结果,并结合结构安全、稳定情况,论证三台阶七步法施工方案的可行性和合理性。

Excavation Scheme Optimization of Weak Surrounding Rock Tunnel

Based on the geology and excavation peculiarity of Wanshan Tunnel on the Hefei to Fuzhou Section of He-Fu Rail Line, and considering the monitoring result of pre-deformation of wall rock and stress of anchor arm, FEM simulation for two kinds of excavation scheme of V-level rock wall, namely six steps method of CD, three steps and seven excavation method is presented in this paper. Numerical result of carven stress and deformation is graphically presented. Furthermore, according to the requirement of structural safety and stability, the feasibility and rationality for these two kinds excavation scheme is investigated.