Analysis of the Influence of Oblique Shield Tunnel Construction on Existing Tunnels: A FLAC3D Modeling Approach

This study presents a comprehensive analysis of the influence parameters associated with the construction of a shield tunnel crossing an existing tunnel at an oblique angle. A three-dimensional model was developed using the finite difference software FLAC3D to simulate the construction process. The influence parameters, including geometric spatial position, shield construction parameters, and surrounding rock soil properties near the existing tunnel, were thoroughly examined. The degree of impact resulting from the oblique shield tunnel construction on existing tunnels was determined based on ground displacement, settlement of the existing tunnel, and changes in soil layers. The study summarizes the identified impact laws and investigates the interaction relationship between newly constructed shield tunnels, soil, and existing tunnels. The findings of this research provide a solid research foundation for ensuring the safety control of shield tunneling in proximity to existing tunnels.