IMPROVEMENT OF CALCULATION ACCURACY FOR PREDICTING OF SEDIMENT DEPOSITION INDUCED BY TSUNAMI RUN-UP USING BEDLOAD LAYER MODEL

Abstract

 In this study, in order to improve the calculation accuracy for predicting the formation of sediment deposition on land induced by tsunami run-up, a bedload layer model is introduced into a tsunami sediment transport model and its improvement is carried out. The bedload layer model assumes the existence of deposition and mobile layers of sediment on a fixed bed. Validation of the model on a flat-bed experiment shows that the introduction of the bedload layer model improves the reproducibility of the phenomenon compared to a typical model. In addition, the possibility of highly accurate prediction of the phenomenon is demonstrated by changing the equilibrium bedload layer thickness and consideration of non-linear changes in the sediment discharge depending on the sediment volume in the target area. However, from the application to the slope-bed experiment using other particle sizes with the same parameters as the flat-bed, it is indicated that further studies are needed to reproduce the phenomenon in other particle sizes.