摘要
本研究於成大水工試驗所之造波水槽進行，將結構物安裝於底床上，利用波高計量測波浪衰減率。測試之波浪條件為不同週期之規則波，分別於不同水深條件下進行實驗，同時為了解結構物之密度和材質帶來的變化，將準備不同的排列方式，和剛性及柔性材質探討之。
實驗結果和前人成果一致，剛性的結構物所造成的波浪衰減率明顯好於柔性材質。而高密度的排列方式所造成的波浪衰減率也明顯大於低密度。長週期的波浪則較短週期的波浪容易透過海生植物，其波浪衰減率較低。
不同的水深部分，找到植生長度與水深比（D/h）這個參數對波浪消散率影響之極值，當D/h=2/3和D/h=5/3時，再度改變水深，已經無法在對波浪消散率有影響。
關鍵字：波浪消散率，水草，剛柔性、排列

Abstract
The purpose of this paper is to investigate the wave attenuation when regular waves pass through the artificial structures .The experiments are condusted in wave flame at National Cheng Kung University, Tainan Hydraulics Laboratory
The experimental conditions are the regular waves with different periods, at different water depths . The study will change arrangement, and the rigid and flexible material in order to know the impact of the density of the structures and material respectively.
The results of the experiments are consistent with previous results of other experiments.The wave damping rate which caused by the rigid structure is obviously better than the flexible material. The wave damping rate caused by the high-density arrangement is also obviously greater than the low one. Long-period waves psss through sea vegetation easier than short-period waves beacuse wave attenuation rate of Long-period waves is lower.
To find the extreme value of the parameter, the ratio of the plant’s length and water depth (D / h), which effect the wave dissipation rate in different depths of water. When D/h=2/3 and D/h=5/3, the parameter could not effect wave dissipation rate anymore, even thought change the water depth.
Keywords: wave damping rate, vegetation, rigid,flexible, arranged

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