區域化比流量之研析及其應用

本研究之主要目的係依據降雨機制之觀點以建立適用於台灣之比流量曲線，以判斷該流域地區所可能發生之最大洪峰流量，並藉由待定參數之意義探討此曲線之型態規則。研究中採用降雨機制之降雨深度－面積曲線及降雨強度－延時－頻率曲線為基本結構，配合集流時間與有效降雨之概念推衍逕流歷線之峰值與時間之關係，以建立推估可能發生最大洪水量之基本原則。此外，以相異流域具不同之地文條件及水文特徵，提出區域化比流量（Regionalized Specific Discharge）概念曲線，進一步以不同重現期與延時之設計雨型為模式輸入，應用合理化公式轉化成逕流量，生成比流量資料群組，以禁忌演算法優選待定係數，進行推估不同重現期之區域比流量曲線。最後透過三維立體概念之應用，藉以發展流域之比流量模方圖，以冀應用於水利工程之水工構造物安全設計。本文以台灣地區之淡水河流域之雨量於流量資料為憑藉，評估模式輸入與應用時之適用性。由結果可知，本研究所採用具有降雨型態概念之比流量曲線確實更適合於描述該研究流域之比流量曲線型態，而重現期概念之引進能快速判斷災害之發生機率，臻以提供台灣集水區防洪規劃之主要依據。

關鍵字

比流量

並列摘要

The main purpose of this study is building a series of specific discharge curves based on the mechanism of the rainfall process for Taiwan. The forms of the curves are detailed analyzed by the meaning of relevant parameters and the final curves are applied to ascertain the probable maximum flood of the project basin. Basis of the conceptions of the rainfall depth－area curve and the rainfall intensity－duration－frequency curve, the time of concentration and the effective rainfall are employed to analyze the relation between the value and the time of the peak discharge and to build a principle of estimating probable maximum flood (PMF). Furthermore, a concept of specific discharge curve based on the regionalized hydrologic parameters and physiographic factors of different project river basins is study uses rational formula with input of the design storms of the different return periods and different durations are employed as inputs in rational formula to simulate runoff and generate the specific discharge data. The Tabu Search algorithm is applied to optimize the unknown parameters of the specific discharge curves for different return periods. Finally, the three-dimensional maps of the specific discharge pattern are established for the safety design of hydrologic engineering. The Damshui River watershed in northern Taiwan is selected as the project area to assess the compatibility of the model. The outcome reveals that the applying of the conception of the design storm modifies the traditional specific discharge curves to a innovative regionalized specific discharge curves. And the return period concept is also added to the project watershed, providing a basis for the planning of flood mitigation in Taiwan.