Structure Analysis Of Submerged Floating Reverse Suspended Cable Cross-sea Bridge

The submerged floating tunnel (SFT), also known as Archimedes Bridge, is an innovative structural typology, is used to cross waterway, such as strait, lake, fjord, etc. The main components of submerged floating tunnel are: tube floating at some depth below the water surface, anchoring system preventing the tube move and shore connection. Submerged reverse suspended cable cross-sea bridge is a new bridge type, which unifies the Archimedes bridge and suspension bridge. This structure has the advantage of the short passing time, very low natural environmental impact, the freedom of choosing construction site, and environmental protection, etc., and provides a choice for crossing wide range water.At first, this article introduced the concept of submerged floating tunnel, listed several kinds of submerged floating tunnel in detail, and submerged reverse suspended cable cross-sea bridge (submerged floating tunnel); It researched the current situation and progress on structural analysis of submerged floating tunnel at home and abroad. Secondly, this article researched suspended cable formula of reverse suspended cable structure, which was different from the cable structure of suspension bridge. This article calculated the static and dynamic characteristic of the structure by ANSYS software, researched the knowledge of ANSYS elements and fluid-structure interaction in numerical calculation. Then, this article analyzed the displacement, cable force and tube stress of structure under water in different loads, and arrived at the pattern by contrasting the test and theory calculation. Due to the material thickness of the model is not enough, this article carried out the numerical analysis of amended model, arrived at the force situation in 5 kinds of different water depth, and analyzed the relationship of the force changing and different water depth. Finally, this article carried out the modal analysis of amended model, which fixed at the ends without the cable structure, and calculated the natural vibration frequency of tube model in the air and under water. This article arrived at the relationship of natural vibration frequency of structure and different water depth in test, and contrasted the calculation result and test result.