Research on Surrounding Rock Stability and Support of Deep-Buried Tunnels under Complex Geological Conditions

As the burial depth of underground space structures such as tunnels continues to increase, complex deformation of the surrounding rock occurs during tunnel excavation under special geological conditions. Once the stability of the tunnel surrounding rock is compromised, it directly endangers the lives and property safety of construction personnel. Therefore, the issue of surrounding rock deformation caused by deep-buried tunnel excavation has garnered widespread attention from all sectors. Based on the mechanical properties and influencing factors of tunnels, and using elastoplastic mechanics theory as a foundation, this study investigates the stress characteristics of circular tunnels under initial stress and the expressions for stress components after stress redistribution, deriving displacement expressions for the secondary stress effects on the chamber surrounding rock.