臺灣博碩士論文加值系統

當結構物設置於碎波帶，或因暴潮水位高漲使得波浪直接於堤面上碎
波時，常會引致結構物受到巨大的衝擊波力。一般於防波堤設計時，通常
允許波浪適度的越波，以減緩結構物受力情形。然而前人對於衝擊波力之
研究多止於不越波的情形之下，故越波對於衝擊波力之影響實乃一個相當
值得探討的課題。 本研究以模型實驗方式量測捲浪型及溢出型衝擊波
作用在不同出水高度的直立堤面之波力值，並以對數常態機率密度函數探
討其衝擊波力之機率分佈，比較不同出水高度之堤面受力增減情形。經分
析結果顯示，直立堤堤頂出水高度的變化會改變衝擊波浪作用於堤面的型
態，本文以不同出水高度所量測之波力歷時曲線進行比較，並由實驗分析
結果發現，捲浪型衝擊波越波時，作用於堤面之波力相較於不越波之波力
，最大可減少30﹪，其中Hc為直立堤頂出水高度， 為衝擊波不越波時之
堤面溯升高程，但在某些出水高度，波力則最大可能增加20﹪。至於溢出
型衝擊波越波時，作用於堤面之波力相較於不越波之波力，最大可減少20
﹪，但在某些出水高度，波力則最大可能增加15﹪。此外，本文亦探討衝
擊波浪不越波時之堤面溯升高程 與碎波波高 之關係，由實驗結果發現捲
浪型及溢出型衝擊波之無因次式分別約為1.23及1.42。本文並以迴歸方式
提出衝擊波越波波峰高程 與不越波時之堤面溯升高程 及碎波波高 之關
係式。

This paper investigates the influence of waveovertopping on
the impact wave force on a vertical breakwater by means of model
experiments. Both of plunging and spilling waves impact on the
vertical breakwater were conducted in the experiment. It was
found that the log-normal probability density function can be
used to describe the distribution of the maximum impact wave
force by non-overtopping and overtopping waves. The time history
of the impact wave force on various heights of breakwaters was
also compared. Experimental results showed that the impact wave
force by the influence of wave overtopping is reducible by 30%
maximum, when compared with the situation of non-overtopping
impact wave on the breakwater. However, the impact wave force
may increase due to the wave overtopping for a certain height of
the breakwater. It was found that the value of the impact wave
force is strongly affected by the completeness of the
compression shock of the impact wave. This paper also presents
the relationship between the maximum water surface elevation of
the impact wave, hm, and the breaking wave height, Hb.
Experimental results showed that the ratios of hm/ Hb are about
1.23 and 1.42 for the plunging and spilling waves, respectively,
for non-overtopping cases. The relationship between the height
of the breakwater and the maximum water surface elevation of the
impact wave of the overtopping wave was also presented
empirically.