A Study on the Watershed of Drainage in plain

• Main Authors: Chih-Wei Huang, 黃志偉
• Other Authors: Chang-Tai Tsai
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/95056423245330561362

碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 91 === Drainage is very important for all of the flood control works. The designed peak flow of drainage is generally in accordance with the area of watershed in plain. However, the terrain in plain area is very evenness, and the height of divide is not enough, then the water flow in the watershed of the drainage will go through to the other watersheds when the rainstorm occurred. Therefore, the influence of other watersheds is needed to consider when we design the peak flow of drainage. The combined flood model is used to simulate the flow in the study. For an advanced study, the flood simulation in HERB typhoon at Pa-Chang River has shown that the combined flood model is well practical, so it can be used to calculate peak flow of drainage. The flood passes through the divide easily due to the height of divide is not enough, for the analysis in calculating the peak flow of Chia-Yi drainage and Ma-Yu-Liao drainage. Also, the degree of flood passing through the divide will increase if the rainfall increases. Besides, the time of concentration will decrease basically if the rainfall increases, but the time of concentration will decrease no longer when rainfall reach critical rainfall or overflow decrease the velocity of flood.