| 研究生: |
黃郁哲 Huang, Yu-Che |
|---|---|
| 論文名稱: |
潰壩式湧波於光滑及粗糙斜坡溯升之試驗研究 Experimental Study on the Runup of Dambreak-Generated Bores on Smooth and Rough Slopes |
| 指導教授: |
吳昀達
Wu , Yun-Ta |
| 學位類別: |
碩士 Master |
| 系所名稱: |
工學院 - 水利及海洋工程學系 Department of Hydraulic & Ocean Engineering |
| 論文出版年: | 2021 |
| 畢業學年度: | 110 |
| 語文別: | 中文 |
| 論文頁數: | 91 |
| 中文關鍵詞: | 潰壩式湧波 、溯升 、溢淹水深 、粗糙斜坡 、水工模型試驗 |
| 外文關鍵詞: | dam-break, runup, inundation, rough slope, laboratory experiment |
| 相關次數: | 點閱:139 下載:0 |
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本論文研究目的係透過潰壩機制生成湧波進行一系列的實驗,以模擬海嘯長波於近岸區域可能的溯升與溢淹現象。實驗以不同坡面粗糙度探討粗糙斜坡對溯升高與溢淹行為的改變,同時為降低任何侵入式儀器對待測流體可能造成之影響。整個實驗流程以非侵入式量測進行,並分別以五種不同下游初始水深進行分析比對(h0 = 0.03、0.06、0.08、0.10、0.12m)。實驗量測湧波條件以福祿數大小做為湧波強度判定標準,通過實驗架設兩波高計間的間距長度與湧波抵達時間進行福祿數的估算,作為湧波強度依據。本實驗量測湧波強度由1.17至2.81不等,對應潰壩上下游水頭差於1.40至8.03之間。通過上述實驗,探討在固定蓄水長度與水平傳動長度的條件下,不同湧波強度於1/10斜坡上的水動力變化。
根據實驗觀測,按水平傳播過程湧波波形的變化分為完全發展湧波、過渡湧波與弱湧波三大類。實驗研究目的為探討湧波於1/10斜坡坡度的溯升高變化與最大溢淹水深,湧波類型的擇選以碎波為主要實驗條件(完全發展湧波與過渡湧波)進行探討湧波於沖刷區溯升高與溢淹水深於岸線的變化。此與現實環境下,海嘯長波發展傳播以碎波湧波形式於內陸沖刷產生溯升現象較為符合。同時亦針對少數未碎湧波條件進行量測,目的為比較其與碎波湧波溯升行為的差異,並論述之。
實驗亦進行光滑斜坡實驗,以提供基準溯升數據。且為確認本研究量測結果之準確程度,量測結果與既有文獻中的數據進行比較。雖潰壩實驗設置不同,但若所設置之潰壩蓄水長度足以產生非衰減湧波,不同配置之實驗結果應可有合理的比較結果。本研究與Barranco and Liu (2021)實驗結果比較,通過計算湧波強度數據轉換之水深條件於本實驗光滑斜坡進行相同的試驗,且參考其實驗觀測湧波波高與溢淹水深計算方法,自由液面變化、最大溯升高及岸線溢淹水深之比較結果相當吻合。以此為參考基準,將其實驗數據與本研究光滑斜坡數據整合延伸溯升經驗公式,並以該經驗公式進行後續粗糙斜坡的實驗與分析。
粗糙斜坡實驗設置與光滑斜坡相同,通過改變1/10斜坡坡面粗糙度,對於兩種不同微觀粗糙度(細砂、礫石等鋪面斜坡)與宏觀粗糙度(結構物不同排列擺設)斜坡進行溢淹水深量測與溯升高變化的探討,以此希冀通過斜坡粗糙度對溯升高與溢淹水深的變化影響,可找出該粗糙度對應之粗糙衰減因子並對其進行量化。實驗數據通過衰減因子轉換與光滑斜坡延伸經驗公式驗證,於溯升高與最大溢淹水深均具良好的相關性,能有效的對不同斜坡粗糙度溯升高與溢淹水深進行初步的推估。
This study presents a series of experiments for the runup and inundation generated by dam-break bores on 1/10 uniform slopes. The experiments were conducted to explore the effects of slope roughness on runup height and flooding characteristics. The entire experiments were carried out using non-intrusive measuring technologies. Five different downstream initial water depths (h0 = 0.03, 0.06, 0.08, 0.10, 0.12m) along with various downstream water depths were considered as so to generate different levels of bore strengths.
To confirm the quality of the present experiments, smooth slope cases were also conducted and compared with available experiments in the literature. These measured data were also be used to compare with those of rough cases, with satisfactory agreements in terms of free surface profiles, runup height and inundation depths. Furthermore, we extended the parameter ranges in terms of bore strengths so as to extend the applicable ranges of proposed runup formulas of dam-break bores.
The experimental setup of the rough slope was identical to that of the smooth slope. By changing the slope surface roughness, the inundation depth and runup measurement of three different roughness slopes were discussed. It was expected that the slope roughness measurement data can be used to determine the reduction factor, γ, with the corresponding roughness levels. The measured data was then verified by using the reduction factor and converted using the empirical formula of dam-break bores on a smooth slope, which can effectively estimate the runup height and inundation depth of different levels of slope roughness.
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校內:2027-01-27公開