Abstract
This research is an experimental study of ripple dynamic for regular waves propagating on horizontal and sloping beds in mid- and high-reflective conditions. Small-scale laboratory experiments were carried out on shoaling region (with non breaking waves) and sediment transport in bedload regime. Our experiments showed the key role that plays the reflection in ripple development. The spatial modulation of the free surface elevation due to reflection created sandbars. Ripples grew up in the region where sandbars were appearing. These patterns were gradually reproduced from breakwater to offshore. The incidence of sandbar created a bi-modal structure of ripple geometry. The larger ripples appeared in the crest of sandbars whereas smaller ripples were found in the troughs. Furthermore, it was found that the evolution of ripples at these two locations can be explained by means of different growth mechanisms. Finally, at equilibrium stages, ripple height converges reaching the same height along the sandbar while ripple length and steepness remains almost constant.References
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