泥砂於河道淤積會造成流路不穩定及河道窄深化加劇，長期下來會使河道變遷，若淤積的區域為易致災河段，例如河道淤積導致流路改變，進而逼近兩岸造成堤坊或護岸基礎沖刷，容易在豪雨事件後危及保全對象，事後投入搶修則會增加成本。河道整理可調整河槽斷面，及河道的剪應力分布，減緩流路擺盪及深槽下切現象。
本研究採用二維泥砂及水力學模式(SRH-2D)針對曾文溪大內橋下游至曾文溪橋上游蜿蜒河段建立二維水理及輸砂模式，模式由河道整理前、後數值高程地形資料(DEM)建立，以實際洪水事件模擬驗證模型可靠度。研究中以各重現期2日暴雨所產的洪水歷線作為情境進行模擬，並比較河道整理前、後的水理現象及沖淤變化，探討河道整理的效益。
研究結果表明：在經過河道整理後的漫灘流量低於河道整理前，可建立濱水帶使小型洪水容易溢淹河道灘地；另外河道整理後的流向將以深槽流向為主，最大流速在10年、20年、50年及100年重現期流量條件下，分別減緩30.0%、29.7%、25.6%及21.6%；底床剪應力經過河道整理後，高剪應力地區皆發生在深槽或深槽銜接灘地處，因深槽已經調整至河道中心因此可以避免河道兩岸受到高剪應力影響造成堤防或護岸的危害，河道整理後剪應力減緩率在45%以上，其中又以100年重現期減緩73.1%為最高；輸砂部分在經河道整理後河道發生沖淤變化的程度降低：沖刷深度的減緩率為26%~49.9%，淤積深度的減緩率在50年以下重現期皆達56%以上，100年重現期則為31.5%。而河道整理後的地形變化皆以淤積現象為主，唯有100年重現期的模擬結果有明顯沖刷發生，顯現河道整理能降低河槽沖淤現象進而減緩河道變遷現象。

The accumulation of sediments in river channels can lead to unstable flow paths and exacerbate channel narrowing and deepening over the long term, resulting in channel changes. River channel regulation involves adjusting the cross-sectional profile of the riverbed to redirect flow that approaches the banks back to the center of the channel. This helps prevent excessive flow toward one side of the riverbank and erosion of levee foundations. Additionally, it adjusts the shear stress distribution in the channel, slowing down the oscillation and deep incision of the flow.
This study utilized a two-dimensional sediment and hydraulic model (SRH2D) to create a hydraulic model for the meandering section of the Zengwun River, spanning from downstream of the Da-Nei Bridge to upstream of the Zengwun River Bridge. Digital elevation model (DEM) data before and after river channel regulation were employed to develop and validate the model through simulations of actual flood events. aiming to assess the benefits of channel regulation.
After river channel regulation aiding small flood control and riparian zone formation. Flow direction shifted towards the deep channel, reducing flow rate with an average velocity reduction of 26.5%. Bed shear stress mainly occurred in the deep channel or its junction with the floodplain, avoiding high shear stress areas near riverbanks that could endanger levees. Sediment accumulation dominated post-regulation, with erosion only in extreme floods, showcasing regulation's positive impact on floodplain protection and flow stability.

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