面對全球暖化導致之氣候變遷，大規模冰山融化造成之海平面上升，近期加劇的極端氣候等等，為了降低上述對海岸造成之威脅，傳統的海岸防護工法，如海堤、護岸、突堤等大型石塊堆積而成的硬性結構，雖然發揮了保護居民生命財產與安全的作用，卻犧牲了人民的親水性與海岸景觀。因而海岸工程朝向永續發展的工法(如柔性工法或複合式工法)。本研究主要以質點影像測速(Particle Image Velocimetry，PIV) 量測孤立波通過不同勁度潛堤之流場特性變化，利用彎曲梁稱重感測器量測其受力變化。試驗模型有三種不同勁度之潛堤，分別為電木、橡膠及矽膠，而每種不同勁度潛堤搭配三種不同波高，分別為5公分、7.5公分和10公分之孤立波。本研究先是以9種試驗條件，以最大波高、最大受力以及彈性潛堤最大變形之三個不同時間點討論流場、渦度及流線變化，在以入射波高為分類依據，對上述之三個時間點進行交叉分析。受力部分則是對其做無因次化分析。結果顯示楊氏模數高的潛堤，因其變形量小，在同一個波浪條件之下，承受之力道最大，並在後方產生較大且速度較快之漩渦，而楊氏模數低的潛堤則相反，承受之力道較小，後方產生之漩渦也較小，並且當潛堤變形，也相應的影響後方漩渦中心，當變形量越大，漩渦也會相應的往底床壓縮，使漩渦中心低於楊氏模數高的潛堤產生之漩渦中心。

In the face of climate change caused by global warming, rising sea level caused by large-scale melting icebergs, and recent intensifying extreme weather, traditional coastal protection methods, such as seawalls and jetties, may not be able to withstand the tsunami. Therefore, coastal engineering turns to the sustainable development methods (such as flexible construction methods or composite construction methods). In this study, Particle Image Velocimetry (PIV) was used to measure different wave heights of solitary waves passing through elastic submerged breakwaters, and the load cell were used to measure the force. Solitary waves were generated by Fenton’s Nine-order Solitary Waves, from 5 cm, 7.5 cm to 10 cm, passed through two elastic submerged breakwaters, and one rigid submerged breakwater in this experimental model. In this study, the changes of velocity field, vorticity, and streamline were investigated at three different time when the solitary wave reached its maximum wave height, the maximum force acting on each submerged breakwater, and the maximum deformation that each submerged breakwater maintain. Three of time position were cross-analyzed. The results show that the deformation of submerged breakwaters change with high Young's modulus magnitude. it could also be observed that the vortex center had a considerable correlation with the deformation of the elastic submerged breakwaters. After eliminating the condition of wave height by using dimensionless number, the force curves in the case of using silicon and rubber approximately coincided each other under the condition of different wave heights.

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