Experimental Study of Free-Surface Profiles of an Aircushion-Type Floating Platform with a Moonpool

A new type of floating platform supported by aircushion units is studied by experimental tests. The platform consists of six hexahedron aircushion units encircling a moonpool in the central. The side walls of aircushion units are extended into the water, and the bottom of aircushion is entirely open to the water. Three kinds of floating platform models are full-aircushion-type platform, full-barge-type platform, and mixed-type platform. Each of them has the same shape and is tested in regular wave conditions. The free-surface elevation inside the aircushion chambers and moonpool is also measured simultaneously as well as the motion responses of the models. The motion responses and the free-surface profile are discussed in this paper. The results show that the motion behaviors of the hexagonal aircushion-type platform are better than those of the barge-type platform in short-wavelength conditions, while behaviors in long wavelength are almost the same. Moreover, the amplitudes and profiles of free-surface elevation of the front aircushion, moonpool, and rear aircushion are different depending on the types of platforms and the wavelength conditions.