Stability Analysis of Shallow Depth Tunnel in Weak Rock Mass: 3D Numerical Modeling Approach

The paper aims at understanding the behavior around a shallow depth tunnel in weak rock mass. Practically such behavior is difficult to completely follow or even estimate in field. To solve the issue, the paper applied modeling using Abaqus/CAE software. In this software, finite element method was used to build a 3D model for the tunnel and its surrounding rock mass. The model was analyzed for stresses and their corresponding strains distribution in addition to displacement vectors before and after tunnel excavation. Results indicate that stresses and strains around the studied tunnel are redistributed due to tunnel excavation. The principal stresses are concentrated on tunnel floor, while shear stress at the tunnel corners. The displacement severely affect tunnel roof. It has also been found that the most affected zone is central floor portion of tunnel at a damage number of 0.75