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Equilibrium beach. Chang Hsien Kuo. 國立交通大學土木工程學系 中華民國 102 年 4 月 11 日. Definition of beach morphology. 淺化帶 (shoaling zone ); 碎波帶 (surf zone ); 沖刷帶 (swash zone) ; 灘線 (shore line ); 海灘 (shore , beach ); 海岸 (coast ); 平台 (berm );
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Equilibrium beach Chang HsienKuo 國立交通大學土木工程學系 中華民國102年4月11日
Definition of beach morphology 淺化帶 (shoaling zone);碎波帶 (surf zone);沖刷帶 (swash zone) ; 灘線 (shore line);海灘 (shore , beach);海岸 (coast);平台 (berm); 內灘 (inshore);外灘 (offshore);沙洲 (bar);灘面 (beach face);灘崖 (beach scarp); 台梯 (step) ;沙谷 (trough)
Type of beach profile Definition: 平衡海灘斷面 (equilibrium beach profile):在同一波浪條件長期作用下,海灘斷面將呈現平衡之狀態。 Type of beach: Type A:暴風海灘 (storm beach) 或冬季海灘 (winter beach) Type B:中間型海灘 (transition beach) Type C:正常海灘 (normal beach) 或夏季海灘 (summer beach) Sunamura andHorikawa , 1974
Slope of beachface Sunamura(1984) tan f
Classification of beach profile SunamuraandHorikawa (1974) Experiment: 4-8 Field:9-18
Equilibrium beach: theory Dean (1977)
Brunn-Dean profile:Equilibrium beach: , Moore (1982) Dean(1991) Kriebel et al. (1998) Disadvantages: Infinity slope at shoreline Monotonic function: infinity depth
Other forms of beach profile Bodge (1992) Hsu e al. (1998) Simple form? Theoretical approach? Bar shape profile?
A and m coefficients of Bruun/Dean profile Artcic beach
Best fitting for a1 a1=03285
Extended equilibrium beach Larson (1991)
Three-parameter equilibrium profile Goodness of fit: overall errors
Discussion Does an equilibrium beach exist in real beach? What is the application of equilibrium to coast engineering? Theoretical approach ?