2024 Volume 80 Issue 16 Article ID: 23-16161
Although studies have been conducted on the overtopping and loss of vegetation during floods, focusing on the hydrodynamic forces and scavenging forces acting on vegetation, it is still difficult to fully understand the phenomena. In this study, a three-dimensional vegetation model was created using aerial laser data for the Asahi River branch in Okayama Prefecture, and a three-dimensional flood flow analysis was conducted to construct a model of vegetation overtopping and loss due to moments by considering the vertical distribution of fluid forces acting on vegetation, which could not be considered in the conventional two-dimensional analysis. The model was constructed by considering the vertical distribution of fluid forces acting on vegetation, which could not be considered in conventional two-dimensional analyses. First, correct data for the overtopping and loss of trees were generated from the difference values of ALB data before and after the flooding, and compared with the analysis. As a result, the validity of the model was confirmed. Furthermore, although the effect of vegetation on the diversion flow rate was considered, the analysis of the vegetation overtopping and runoff model at the planned high water flow rate showed that the effect could be negligible.
