Analysis about Vibration Influence on Surrounding Environment by Subway Four-holes Overlapping Multi-tunnels under Train Loads

The research about subway four-holes overlapping multi-tunnels is mainly concentrated in construction feasibility and deformation control problems occurred in the process of construction, but environmental vibration caused by subway four-holes overlapping tunnels is lack of related research. According to the structure characteristic of subway four-holes overlapping multi-tunnels, a certain interval of Wuhan metro line 2 and line 4 was selected to establish the finite element model by ANSYS and the vibration influences on the surrounding environment under different combination of train running were studied. The results show that the vibration intensity of measure points are mainly affected by depth of vibrating source and horizontal distance from vibrating source, the vibration are mainly in vertical direction. For ground vibration, the larger distance from vibration source, the smaller intensity of vibration, and within a certain distance vibration damping is clear, and then slowly decreases. The vibration intensity of the measure points which underground may be more apparent than those on the ground when in the same horizontal position. For the same depth of underground station, the smaller distance from vibration source, the greater intensity of vibration. The situation of two or more trains running in the multi-tunnels at the same time is more complex than one train running, which needs further study.