To reduce vertical displacement and direct stress of a large float, by providing many supporting floats hanging from the bottom surface of a deck, and setting the ratio between a typical value D of these supporting floats and a distance Ls between the centers of the supporting floats placed at the bottom surface of the deck so as to become a specific value.
Supporting floats 2 are structured so as to hang from the bottom surface of a large float 1, and horizontally arranged in a grid pattern or in a slanting grid pattern. In a case where the cross sectional shape of each supporting float 2 is a circle, the diameter thereof is regarded as a typical diameter D. In a case where the cross sectional shape of each supporting float 2 is a polygon, the diameter of a circle with an area equal to the cross sectional area is regarded as a typical diameter D. The ratio D/Ls between this typical diameter D and a distance Ls between the centers of the supporting floats 2 is determined based on the maximum height of waves generated at a site where the large float 1 is placed. For example, in the case of evaluating at a stress λmax=8 g/mm2, D/Ls is set to 0.84 or below in the case of placing the large float 1 in an area sea where the maximum wave height is approximately 2 m, 0.58 or below in the case of approximately 3 m, and 0.32 in the case of approximately 7 m.
KAGEMOTO HIROSHI
MURAI MOTOHIKO
KAGEMOTO HIROSHI
MURAI MOTOHIKO