Berm and Dune Erosion during a Storm

The prediction of berm and dune erosion during a storm is essential for storm damage assessment. Simple and transparent formulas for the cross-shore and longshore transport rates of suspended sediment and bed load on beaches are proposed and incorporated into a combined wave and current model to predict the berm and dune erosion under normally and obliquely incident irregular waves. Two small-scale experiments for two different berm profiles were conducted for the calibration of the developed numerical model. The calibrated numerical model is shown to predict the measured berm and dune erosion in these experiments as well as dune erosion measured in three large-scale tests with errors less than a factor of two. The numerical model is used to examine the effects of the wave period and incident wave angle on the berm and dune erosion. These effects are computed to be within a factor of two.

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