Physical experiments on the hydrodynamic response of submerged floating tunnel against the wave action

Abstract

Submerged floating tunnel (SFT) is a unique marine structure whose actual realization has yet be made in the world. Assessment of hydrodynamic performance of SFT under wave loading is one of important factor in the design of SFT structure. This study investigated this issue by conducting physical experiments in a two-dimensional wave flume by generating regular waves of different heights and periods under different conditions of buoyancy to weight ratio (BWR) and water depth as well. The experimental results showed that the surge and pitch motions of the tunnel body linearly increased with wave height and period, while the heave motion was rather insignificant unless both quantities were comparatively large as the design wave. Similarly, maximum tensile force on the tension legs and the pressure loads on the tunnel body showed proportional relationship with wave height and period. Meanwhile, the magnitudes of major measured quantities generally showed decreasing trend according to increase of water depth but decrease of BWR.This study investigated this issue by conducting physical experiments in a two-dimensional wave flume by generating regular waves of different heights and periods under different conditions of buoyancy to weight ratio (BWR) and water depth as well. The experimental results showed that the surge and pitch motions of the tunnel body linearly increased with wave height and period, while the heave motion was rather insignificant unless both quantities were comparatively large as the design wave. Similarly, maximum tensile force on the tension legs and the pressure loads on the tunnel body showed proportional relationship with wave height and period. Meanwhile, the magnitudes of major measured quantities generally showed decreasing trend according to increase of water depth but decrease of BWR.