Study on Bifurcating Form and Mechanical Behaviors of Underground Interchange Tunnel
|School||Beijing Jiaotong University|
|Keywords||Interchange Underground Interchange Tunnel Asymmetric tunnels with small spacing Plane Bias Tunnel|
In order to alleviate the traffic pressure on the ground , more and more cities started building underground expressway . Many cities and even the ground on the overpass moved underground , tunnels built underground interchange . And the construction of a single tunnel to be built underground highway tunnel Interchange will encounter a variety of problems that do not exist in a single tunnel design , construction and no direct experience of the difficulty will increase greatly. In this paper, the National 863 Plan Interchange underground interchange tunnel construction technology research to expand on one of the key technologies in underground interchange Interchange , the main tunnel and ramp tunnel bifurcation part of the bifurcated form and related technologies . Firstly, through research and engineering analogy Underground Interchange interchange in the main tunnel and ramp tunnels both bifurcation and the applicable conditions Variable Section transitional forms , the two forms of span span widening value were discussed , given the reference value . Secondly, calculated by the numerical simulation analysis to study the behavior of the asymmetric bifurcation appear small spacing tunnel construction mechanics , pitch changes in the variation of the comparative analysis of the main tunnel and ramp tunnel mutual influence and the influence of the tunnel . Finally, through numerical simulation analysis of the plane bias tunnel , deformation and force characteristics come to the intersection around the surrounding rock and support with the the ramp tunnel excavation depth changes and the area affected .