MODEL FOR PREDICTING BATHYMETRIC AND GRAIN SIZE CHANGES BASED ON BAGNOLD’S CONCEPT AND EQUILIBRIUM SLOPE CORRESPONDING TO GRAIN SIZE COMPOSITION

Yasuhito Noshi, Takaaki Uda, Masumi Serizawa, Takayuki Kumada, Akio Kobayashi

Abstract


A model for predicting bathymetric and grain size changes considering the equilibrium slopes corresponding to each grain size and its composition was incorporated into the BG model proposed by Serizawa et al. (2007). The model was applied to predict the beach changes at Kemigawa Beach. The cross-shore sorting of sand, in which the grain size gradually decreases with increasing depth, and the formation of a gradually changing longitudinal slope were accurately reproduced. The model was also applied to predict the selective accumulation of fine sand in a navigation channel after dredging and its impact on the nearby coast.

Keywords


Bagnold’s concept; equilibrium slope; navigation channel; bathymetric change; grain size change

References


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