Analysis of Influence of Anchor Excavation of Shallow Buried Bifurcated Tunnel and Adjacent Tunnel on Overlying Buildings

In order to analyze the effects of excavation of shallow buried bifurcated tunnels with tunnel-type anchorage in close proximity to each other on the structural safety of overlying structures and on the structural stability of the tunnels due to the tensioning of the main cables of the tunnel anchors, combining with engineering examples and on the basis of rock mechanics tests, three-dimensional finite element numerical simulation method was adopted. The influence of tunnel and tunnel-type anchorage excavation on surrounding rock deformation and foundation settlement of overlying buildings and the influence of main cable tension of anchor plug body of anchorage tunnel on small clear distance tunnel were analyzed, which provided scientific basis for tunnel design and construction. The simulation results show that the excavation of tunnel-type anchorage holes and bifurcated tunnels has a greater impact on the overlying buildings but still meets the specification requirements, and the impact of tunnel anchor main cable tensioning on the tunnel is basically controllable.