Dynamic transient analysis of a submerged floating tunnel under impact loading

Abstract

A submerged floating tunnel (SFT) is an innovative structure constructed in the deep sea that connects continents or continents and islands. Submarines, underwater vehicles, and marine life may infrequently collide with an SFT, causing damage or interfering with the operation of the SFT. In this study, collision tests were conducted. To analyze the dynamic transient response of the SFT, the impact load was varied using different velocities and masses; a total of 288 impact tests were performed by adjusting the impact location (top, middle, and bottom) and the type of mooring line. The largest displacement occurred when the impact location was at the top of the SFT. The stability of the SFT was examined by installing four types of mooring lines. The presence of the central support line suppressed the displacement of the SFT, and as the installation angle of the mooring lines decreased, the behavior of the SFT stabilized. The impact force of the SFT was linearly correlated with the velocity and proportional to the square root of the mass of the impactor. The results of this study can be used to identify the vulnerable locations on the SFT that require meticulous monitoring to ensure safety.