本研究以實驗的方法,在5公分寬的壓克力渠道上堆出固定比例不同體積之壩,經由上游給定之穩定入流量,觀察此壩體在不同渠道坡度下之破壞現象。實驗中,壩體一律以直徑2mm的圓形細磨瓷石,以統一10:1 之長高比例來堆出不同體積大小的壩體。上游入流為定水量56.75 cm3/sec。 在分析的部分,利用電荷耦合攝影機(Charge Coupled Device,CCD,camera)擷取顆粒流場中的質點影像後,利用影像處理的方式,增強擷圖中顆粒可被辨識的能力,搭配流場顯影的方法繪出破壞時的顆粒流場速度分佈、形狀變化,並且由壩體破壞時下游坡面斜率的變化得知壩體破壞機制的不同。而透過底床坡度的變化可知,當入流量固定、底床坡度增加時,壩體潰壞所需的時間也更短。
This study observes the failures of dam-break with steady run-off at a 5cm wide channel , in the conditions of different dam sizes and different channel gradients. In the experiment , all dams are composed of porcelain circle particle …..and piled up in the length-high proportion 1:10 . It supplies 56.75 cm3/sec steady flow upstream . In the analysis , this study gets the particle image in particle flow by charge coupled device . In order to plot the flow field velocity and appearance change , it enhances the image ability to be identified by image processing . By observing the downstream slope, it can distinguish the different forms of dam failure. With stationary inflow , it needs more time for dam failure when slope of seabed becomes steeper.