Three-Dimensional Numerical Study of the Mechanical Characteristics of a Rectangular Immersed Tube Tunnel

There are many different kinds of cross-section structure forms in the rectangular immersed tube and their stress distributions are complex. In order to confirm the rectangular immersed tube structure features, the finite element software ANSYS is used to analyze the characteristics of the force in the immersed tube structure under different settlement conditions combining specific geological conditions and engineering design requirements. The worst tension parts of the immersed tube are the inner side of the lane floor and the lower side on the outside of the side wall. Chamfer or fillet could be set inside the base lining turning points to reduce stress concentration levels. Combined with tensile stress directions, this paper puts forward feasible suggestions on the structure of the internal reinforcement layout.