水文分析實作報告

Abstract

本研究之水文分析為水利工程規劃設計之前置作業，水文分析結果之設計流量為水利工程據以設計之標準。本研究利用集水區內雨量站及流量站的水文資料，推求各重現期的洪峰流量。操作流程先用徐昇式多邊形法求取集水區平均雨量，並據以進行集水區的暴雨頻率分析，製作出降雨強度－延時－頻率曲線，接著利用降雨強度公式求出各重現期的降雨量值；採用交替組體法的道設計雨型。接著採用三角形單位歷線法及合理化公式推估洪峰流量，經由評估後採用合理化公式之推估尖峰流量作為設計流量。

In this study, we calculated the design flow in the watershed for various return periods. The first step is using Thiessen’s polygon method to estimate the average rainfall data over the watershed. Then, the rainfall frequency analysis was performed to make the intensity-duration- frequency curves. The design hyetographs was made by using the alternating block method. Both the triangular unit hydrograph and the rational formula were used to calculate the peak discharges under different return periods. Finally, the peak discharges calculated by the rational formula were used as the design flows.