PREDICTION OF TOPOGRAPHIC CHANGES AROUND A RIVERMOUTH SUBJECT TO OBLIQUELY INCIDENT WAVES AND EFFECT OF TRAINING JETTY

Abstract

 A model for predicting topographic changes around a river mouth subject to obliquely incident waves was developed using the BG model (a model for predicting three-dimensional beach changes based on Bagnold’s concept) in place of the contour-line change model proposed by Iwase et al. A field observation was carried out at a small river flowing into Lake Hinuma on the northeast side of Oyazawa-bana sand spit to verify the applicability of the model. Using this model, the mechanism of the development of the terrace offshore of the river mouth subject to the obliquely incident waves was investigated as well as the study of the effect of the training jetty to the topography around the river mouth.