However, the validity and accuracy of using regular waves in the evaluation of wave attenuation performance of floating breakwaters have not been thoroughly discussed in the open literature. There is no doubt that the use of regular waves is simple for practicing engineers designing floating breakwaters. In some current design guidelines for floating breakwaters, the transmission coefficient is estimated based on the assumption that the realistic ocean waves may be represented by regular waves that are characterized by the significant wave period and wave height of the wave spectrum. The effectiveness of a floating breakwater design is assessed by its wave attenuation performance that is measured by the wave transmission coefficient (i.e., the ratio of the transmitted wave height to the incident wave height or the ratio of the transmitted wave energy to the incident wave energy). A floating breakwater outperforms its bottom-founded counterpart with respect to its environmental friendliness, cost-effectiveness in relatively deep waters or soft seabed conditions, flexibility for expansion and downsizing and its mobility to be towed away.

Floating breakwaters have been used to protect shorelines, marinas, very large floating structures, dockyards, fish farms, harbours and ports from harsh wave environments.

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