本研究以浮式減能船為研究對象，透過一系列水工模型試驗，全面探討其在海岸侵蝕防治中的應用潛力，評估其在不同波浪條件下的能量衰減效率、底床地形變化及結構適應性，並與柔性減能網）進行了系統計算比較分析。研究目標在於驗證浮式減能船在實際沿岸環境中的效能，並為後續應用提供科學依據。
實驗結果顯示，浮式減能船在中至高能量波浪條件下能顯著減少波浪能量，其平均波能衰減率在不同波浪條件下表現如下：季風波17.8%、颱風波I 28.5% 以及颱風波II 39.3%。顯示出海域應用的潛力。此外，浮式減能船的動態漂浮特性使其能夠隨波浪變化自我調整，減少結構受力集中現象，進一步提升能量耗散效率。
在泥沙淤積與底床穩定性方面，浮式減能船亦展現出顯著優勢。研究發現，浮式減能船後方（ab區）普遍呈現穩定的泥沙沉積現象，特別是在變動水位的颱風波I 條件下，其後方區域出現了顯著的最大淤積量。這表明浮式減能船能有效促進泥沙沉降，減少底床侵蝕並穩定岸線，符合其作為海岸防護結構的設計目標。此結果反映了浮式減能船在強流動水環境中的沉積能力，為改善沿岸地貌變遷提供了可靠的工程依據。
此外，浮式減能船在安裝深度上的靈活性亦是一大優勢。實驗結果顯示，從水深-4 cm至-2 cm的現場水深2公使及水深1公尺)(安裝試驗中，浮式減能船即便在波浪條件有所變化的情況下，仍能維持高效的波能衰減與泥沙穩定效果，顯示其在動態沿岸環境中的應用潛力。這意味著浮式減能船能適應不同海岸地形與水深變化，為沿岸防護結構的設計與部署提供了更大的靈活性與適應性。
相較於傳統的減能網，浮式減能船在維持穩定泥沙沉積與減少局部沖刷方面表現更佳。儘管減能網在波能衰減方面亦具有一定效果，但由於其固定結構設計，常導致後方流速集中，形成強烈的局部沖刷現象，進而造成底床不穩定性。相對而言，浮式減能船的靈活漂浮特性能更有效地分散波浪能量，避免了流速集中與沖刷效應，同時在結構後方形成更穩定的沉積區，顯著降低了長期底床變形的風險。綜合而言，浮式減能船作為一種創新的海岸防護結構，具有能量衰減、岸線穩定以及高靈活性等多重優勢，展現出良好的實務應用潛力。為進一步強化其應用效益，未來研究應聚焦於更廣泛的波浪條件與環境變化下的效能驗證，同時探索不同結構模組的組合設計與多層減能結構配置，並進行長期現地觀測，以全面優化其防護效能，確保沿岸地區的長期穩定性與防護效果。

This study focuses on the Derosion Boat as a novel flexible coastal protection structure, aiming to evaluate its potential application in mitigating coastal erosion through a series of hydraulic model experiments. The primary objectives of this research include assessing the wave energy dissipation efficiency, seabed morphology changes, and structural adaptability of the Derosion Boat under various wave conditions. Additionally, comparative analyses with the Derosion Lattice, a traditional flexible energy dissipation structure, were conducted to establish performance benchmarks. The overall goal is to verify the effectiveness of the Derosion Boat in real-world coastal environments and provide scientific support for its future application.
The experimental results demonstrate that the Derosion Boat can significantly reduce wave energy under moderate to high energy wave conditions. The average wave energy attenuation rates observed in different wave scenarios were as follows: 17.8% for monsoonal waves, 28.5% for Typhoon Wave I, and 39.3% for Typhoon Wave II, indicating substantial potential for high-energy coastal applications. Furthermore, the dynamic floating characteristic of the Derosion Boat allows it to adjust to changing wave conditions, reducing localized stress concentrations on the structure and enhancing overall energy dissipation efficiency.
In terms of sediment deposition and seabed stability, the Derosion Boat also exhibited significant advantages. The study found that the rear zone (ab zone) of the Derosion Boat consistently exhibited stable sediment accumulation, particularly under variable water level conditions with Typhoon Wave I, where the maximum sediment deposition was observed. This indicates that the Derosion Boat can effectively promote sediment settling, reduce seabed erosion, and stabilize the shoreline, aligning with its design goals as a coastal protection structure. These findings provide robust engineering evidence for its effectiveness in mitigating coastal erosion under high-energy hydrodynamic conditions.
Moreover, the Derosion Boat demonstrated significant flexibility in installation depth, which is a critical advantage for adapting to various coastal environments. Experimental results from installations at depths ranging from -4 cm to -2 cm indicate that the Derosion Boat can maintain high wave energy dissipation and sediment stabilization performance despite varying wave conditions, highlighting its potential for use in dynamic coastal settings. This adaptability suggests that the Derosion Boat can effectively respond to changes in seabed topography and water depth, providing greater flexibility and applicability for coastal protection designs.
Compared to Derosion Lattices, the Derosion Boat exhibited superior performance in maintaining stable sediment deposition and reducing localized scouring. While Derosion Lattices are effective in dissipating wave energy, their fixed structure design often leads to concentrated flow velocities behind the structure, resulting in intense localized scouring and unstable seabed morphology. In contrast, the flexible floating nature of the Derosion Boat allows it to more effectively distribute wave energy, minimizing flow concentration and scouring effects, while promoting the formation of a stable sediment deposition zone behind the structure, significantly reducing the risk of long-term seabed deformation.
In conclusion, the Derosion Boat, as an innovative coastal protection structure, offers multiple advantages including energy dissipation, shoreline stabilization, and high flexibility, demonstrating significant practical application potential. To further enhance its effectiveness, future research should focus on validating its performance under a broader range of wave conditions and environmental changes. Additionally, the exploration of multi-layered structures and the integration of different modular configurations, along with long-term field observations, will be essential for optimizing its protective performance and ensuring the long-term stability of coastal regions.

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