臺灣大學: 土木工程學研究所劉格非江宏晟Chiang, Hung-ChengHung-ChengChiang2013-04-012018-07-092013-04-012018-07-092012http://ntur.lib.ntu.edu.tw//handle/246246/255526本研究在室內渠槽堆置土壩，探討壩體由兩種粒徑以不同比例組成和不同流量沖刷下的破壞現象。本實驗使用兩種不同粒徑D的顆粒(2mm和9.5mm)去堆出實驗所需的壩體。在固定坡度下，我們觀察在不同的流量Q下(180cm^3/s至1640cm^3/s)不同粒徑組合之壩體與流量所產生的破壞形態。實驗過程發現流量由小而大會有(1)未破壞、(2)基角沖刷破壞、(3)溢流破壞和(4)綜合型破壞四類狀態。由實驗結果顯示，壩體發生破壞的時間長短主要是隨入流流量而改變；在流量相當的情況下改變大小粒徑組成對壩體發生破壞的開始時間影響不大。壩體粗顆粒的百分比越大發生的臨界破壞流量就越大。當粗顆粒的百分比增加到40%以上時，壩體內部滲流出的流量會帶走大部分小粒徑的砂造成壩體滑動，絕大部分大顆粒的砂會留在原地，即使上游水持續沖刷壩體也會形成相對穩定的狀態，要使壩體整個潰決就必須加大流量就會產生既有滲流又有溢流的綜合型破壞或是溢流破壞的情況。In this study, we discuss the dam failure pattern through experiments. The material used is composed of two particles with diameter 2mm and 9.5mm. Under the same bottom slope, we recorded the failure patterns with different inflow Q (180cm^3/s to 1640cm^3/s ) and different particles size combinations. The observed failure pattern can be classified into three categories (1) no destruction (2)progressive failure from toe (3) overtopping and(4)Comprehensive destruction . The experiment results showed that the main factor affecting how long the dam will start to fail is the inflow rate. There is a minimum flow rate for the dam to have any failure. As the course particle increases in percentage, the minimum flow rate required for failure also increases. As flow rate increases from the minimum flow rate, the toe erosion following by progressive failure occurs first. Overtopping failure will occur for even larger flow rate. If the percentage of course particle is high enough, overtopping failure will never occur.4051928 bytesapplication/pdfen-US堰塞湖基腳沖刷溢流破壞nature damovertoppingprogressive failurethesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/255526/1/ntu-101-R97521322-1.pdf