Observation on Bed Variation in a Meandering Like Flume with River Training Structures
清水康行・ギリ－サンジェ－
Yasuyuki SHIMIZU 1 and Sanjay GIRI 1
1Dept. of Hydroscience & Environmental Engineering, Hokkaido University
要旨
An explorative physical model study reported herein was conducted in a mildly meandering like laboratory flume with spurs as river training structure in order to observe the bed variation near the spurs as well as in further down stream region. Study was performed under the clear water condition using two different grain sizes (0.28mm & 1.2mm). In this study, temporal bed variation near series of spurs in different part of bend was determined simultaneously using long run experiments under various hydraulic and experimental conditions. Moreover, bed form induced by spurs in further down-stream region was also observed. It has been shown that temporal variation of relative scour depth can be generalized using a similarity number referred to as Strouhal number. An attempt was made to observe vegetation impact on local bed evolution having planted living vegetation (alfalfa) near the spur region under laboratory condition.
Key Words: structure-induced bed-forms, clear water scour, temporal development of scour, vegetation, alfalfa