Numerical Analysis of Influence of Intersection Angle of Metro Overlapping Tunnels on Tunnel Construction

Abstract

Taking Kunming subway first phase project ring--Kunming section overlapping tunnel as the project background, using MIDAS/ GTS and finite element program to simulate shield excavation process, using first-down and then-up excavation methods and different overlapping angles as construction conditions, analyzing the influence of overlapping tunnel construction on surface settlement and segment internal force under different overlapping angle conditions. The results show that, the surface settlement and segment internal force change with the change of overlapping angle, overlapping angle decreases, surface settlement range increases, while the maximum settlement value and segment stress both decrease.