Interaction and Treatment for Tunnels Orthogonally Traversing Large Bedrock Landslides

摘要

When a tunnel orthogonally traverses a large bedrock landslide, the interaction between the tunnel and the bedrock can easily disturb the stability of the slope and deformation of tunnel structures. In this work, Jimei tunnel in southwest China was studied as an example. The physical parameters of the landslide were inverted based on uniform design and a radial basis function neural network model and a model was established for the interaction of tunnel and bedrock landslide. Simulations showed that tunnel construction resulted in tensile failure at the trailing edge of bedrock landslide and clear deformation in the left line of the tunnel. This was consistent with the field damage observed in this work. A comparative analysis was performed of structural stability after the application of three schemes of earth-rock clearing, load-reducing, and slide-resistant pile arrangements. Optimal measures for landslide reinforcement were determined to ensure smooth tunnel construction and reduce project cost. Two years of continuous post-construction monitoring indicated that the stability of tunnel and landslide was preserved and treatment goal was achieved. Calculation methods and control measures developed in the current research for tunnels orthogonally traversing bedrock landslides provided a useful reference for similar projects in the future.