波動通率法在海堤斜面上溯升計算之應用

Application of Wave Momentum Flux in Computation of Wave Run-up on Seawall

莊甲子(Jea-Tzyy Juang) ； 林朝福(Chao-Fu Lin)

《建國科大學報》 28卷2期 (2009/01) Pp. 53-67

https://doi.org/10.6995/JCTU.200901.0053

摘要

Hughes(2004)提出波浪動量通率參數計算法以預測波浪溯升高，其法與利用波浪溯升水體位能計算法(Cross and Sollitt, 1972)以計算波浪溯升有很顯著之不同。本研究利用光滑與階梯堤上波浪溯升試驗量測結果以比較該兩種計算法之差異性和計算結果之準確性。在波浪溯升水體位能計算法方面，本研究利用Isaacson (1991)在波浪反射率研究中所提出的三波高法來計算反射率，求其和碎波相似參數與斜堤坡度間之關係，並引用Ahrens et. al.(1981)及Neelamani and Sandhya (2005)等之反射率的研究成果加以比較，結果甚為相符。在相對溯升高的計算方面，經用試驗結果和上述兩種預測法之計算結果比較後可發現，波浪動量通率參數計算法較波浪溯升水體位能計算法可得較為準確之波浪溯升高的預測結果。

關鍵字

波浪動量通率參數 ； 波浪溯升 ； 位能 ； 反射率 ； 碎波相似參數

並列摘要

Hughes (2004a、2004b) presented a new non-dimensional wave momentum flux parameter to predict the maximum wave run-up height on seawall. His predict method was differentiate to the potential energy method that proposed by Cross and Sollitt (1972). In this study, we use the experimental data of wave run-up in several different dike slope to compare with the values that computed by the above mentioned two prediction models. In calculating procedure, the three wave gages meter analysis method that proposed by Isaacson etc. (1991) to estimate the wave reflection coefficient was used. The correlation between the surf similarity parameter to the slope angle of smooth and step dikes was computed. Meanwhile, the result of analysis is compared to the results which presented by Ahrens (1981) and Neelamani and Sandhya (2005). We find the tendency of correlations was similar. As to the accuracy of predicted wave run-up height that compare with the experiment data, we can see the wave momentum flux prediction method is better than the wave potential energy method in both the smooth sloping dike and the stepped dike surface.

並列關鍵字

Wave momentum flux parameter ； wave run-up ； potential energy ； reflection rate ； surf similarity parameter