NUMERICAL EXPERIMENTS ON THE BEHAVIOR OF BARS CONSIDERING THE BANK STRENGTH

Abstract

It is of interest to investigate how the behavior of alternate bars leads to channel development by taking bank strength into consideration, which is affected, in turn, by bank vegetation in natural rivers, in order to design stable channels when straightening rivers or building navigation canals. This study examined the behavior of alternate bars in a channel with erodile banks numerically, by considering the bank strength, which is influenced by bank vegetation in natural rivers. The lateral widening rate of the channel, bar migration speed, and wavelength were studied numerically when the channel remained nearly straight. The bars migrated more slowly as the aspect ratio increased. In a channel with strong banks, the bars migrated with speed, and the dimensionless bar was higher. Our numerical experiments showed that the behavior of bars differed with bank strength under the same hydraulic conditions.