Bedform effect on the bed-load transport rate using a comparison between two bedform (flat and standing bedform)

Abstract

In this research, the impact of bedform on the bed - load transport rate was studied through experiments. The experiments were conducted on two cases, one when the bedform was flat, and the other when the bedform was standing wave. The arrival time is the time of bed - load reaches a reference surface at the end of the flume. Noted that the arrival time of the bed - load to the end flume when the bedform as flat differs from the arrival time when the bedform as standing wave, It was found that the arrival time in the case of flat bedform is less comparing to the case when the bedform is standing wave. Index form factor (L*/L) was proposed to distinguish between the flat bedform and the standing wave bedform, this factor was introduced in dimensional analysis with the other variables affecting the prediction of bed - load transport rate formula. Linear regression was found to predict formula for index form factor L*/L and also prediction formula for computed the bed - load transport rate (qs) with high R-square. The results from predicted formula were verified by comparing them with other researchers’ formal’s using statistical measures. At long last, it was found that the amount of the bed - load transport rate when the bedform was a flat is greater than the amount of the bed - load transport rate when the bedform was standing wave. Since the value of the bed - load transport rate has to do with the decision to maintain the unlined channels and thus it affects the cost of maintenance of the unlined channels.