Underwater Small Spacing Shallow Tunnel In Mutual Influence

As the rapid development of China's economy, the number of tunnels is increasing. As it is restricted by the factors such as specific topography conditions, the traditional separated tunnel can't meet the requirements, the number of small spacing Tunnel is increasing. But in China, the emergence and research of small spacing Tunnel relatively show later. Especially in shallow underwater tunnel with small space, there are no definite standard, theoretical research lagging behind the engineering practice. Therefore, the systematic study of underwater tunnel with small space is significant. Based on the project of Changsha Liuyang river shallow underwater tunnel with small space, this paper studies the interaction systematically between the caves of the underwater tunnels with small spacing using monitoring and FEM.(1) According to the actual condition of this project, a detailed monitoring program was constituted.(2) Through monitoring the adjacent tunnel and get a lot of first hand information, including the law of the development of surrounding rock convergence, water pressure, surrounding rock pressure and superficial pressure stress of the lining was found. According to the result of analysis, conclusion was made that the tunnel is safe.(3) Adopting MIDAS/GTS software to establish 3D model. Simulate the interaction between the caves of the tunnels with small spacing from the angel of tunnel spacing. Through computation, get the tunnel displacement and plastic deformation of surrounding rock in different spaces. Then the paper compares the simulation results with the measured results.