Applying Frequency Analysis of Storm Surge to Predict Flooding River Stage

• Main Authors: ZHou,Zhe-Yong, 周哲雍
• Other Authors: Liu,Wen-Cheng
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/w96gsp

碩士 === 國立聯合大學 === 土木與防災工程學系碩士班 === 105 === Taiwan is hit by typhoons every year. The water level will be enhanced as a result of the decreasing the atmospheric pressure during typhoon events. The probability of inundation would be increased and result in property losses of estuaries and coastal nearby residents when the high tide meets the typhoon with strong rainfall. Therefore, the issues of storm surge and river flooding are urgent need to be studied. In the present study, 44 historical typhoons and 360 synthetic typhoons were used to simulate surge heights in Taipei Tamsui River estuary using ADCIRC model. The maximum surge heights were then conducted with frequency analysis to generate surge heights under different return periods in accordance with historical and synthetic typhoons. The combination with surge height and astronomical tide was used to force downstream boundary condition using one-dimensional (1D) unsteady flow model to simulate flooding river stages in Tamsui River watershed. The simulated results reveal that the generated surge heights under 200 and 500 return periods according to historical typhoons will result in overbank flow. The generated surge heights under 100, 200, and 500 return periods based on synthetic typhoons will produce overtopping in river.