Abstract:The evolution characteristics of compound fluvial channels with totally movable-bed that was made of non-uniform sediment were studied experimentally under clear water. They include the variations of stabilized width and bank erosion along the channel after the riverbed is roughened completely. Before the experiments, the compaction of sand was finished by slowly flowing water. After the whole self-formed channel was submerged for some time, the water was discharged slowly; then, the movable-bed channel was restored. The original and eroded bed surface levels were probed by using a total station and the discharge and water levels were measured by a triangular weir and automatic water level meter, respectively. The results show that with increasing deposition of sediment, the flow depth in the main channel becomes shallow, leading to the force under which sediment particles start to move is decreased. When the channel becomes stabilized, the channel width varies along the channel. After the riverbed is roughened totally, the width of the main channel is increased and the retreat rate of river bank becomes small along the channel. Under the action of clear water, the floodplain and bank of the main channel are eroded and the eroded area decreases along the channel. This is consistent with decrease in the cross-section averaged velocity along the channel.
杨克君, 聂锐华, 刘兴年. 清水作用下全动床复式河槽河床演变特性[J]. 排灌机械工程学报, 2013, 31(11): 954-957.
Yang Kejun, Nie Ruihua, Liu Xingnian. Evolution characteristics of compound fluvial channels with totally movable-bed under clear water. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(11): 954-957.
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