Abstract
For predicting discharge hydrograph and progress of inundation flow caused by the levee breach, it is important to evaluate inundation discharge hydrograph precisely. In this study, utilizing that the change in hydraulic and geometrical conditions during the flood appears in the temporal changes in water surface profiles, we developed a numerical computation model to estimate inundation discharge hydrograph using the unsteady two-dimensional flow equations and the temporal changes in water surface profiles including effects of the levee breach. To verify the validity of the numerical model, we carried out field experiments of levee breach of a channel constructed on a bar in the Joganji River. Comparing with experimental and calculation results, we showed that this method was useful to evaluate the inundation discharge hydrograph by the levee breach. Furthermore, we raised issues to be solved for application of this method to real time inundation prediction of real rivers.
