Experimental simulation of shoreface nourishments under storm events: A morphological, hydrodynamic, and sediment grain size analysis

• Published in: Coastal engineering (Amsterdam) Vol. 58; no. 2; pp. 184 - 193
• Main Authors: Grasso, F., Michallet, H., Barthélemy, E.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01-02-2011; Elsevier
• Subjects: Beach morphodynamics; Beaches; Changing wave climates; Dissipation; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Engineering geology; Engineering Sciences; Exact sciences and technology; Fluid mechanics; Fluids mechanics; Geomorphology, landform evolution; Grain size variation; Marine and continental quaternary; Mechanics; Offshore; Offshore engineering; Offshore structures; Physical modelling; Physics; Sediment transport; Sediments; Simulation; Storms; Surficial geology; Wave skewness; Beach morphodynamics; Changing wave climates; Grain size variation; Physical modelling; Wave skewness; Sediment transport; onshore; waves; models; hydrodynamics; digital simulation; climate; bars; coastal environment; offshore; beaches; grain size; sediment transport; erosion; skewness; flumes; storms
• ISSN: 0378-3839; 1872-7379
• DOI: 10.1016/j.coastaleng.2010.09.007

This study focuses on barred beach shoreface nourishments physically simulated in a wave flume. The attack of a schematic storm on three different nourishments is analysed. The apex and waning storm phases lead respectively to offshore and onshore sediment transports. Nourishments in the trough and on the outer bar feed the bar and increase wave dissipation offshore. The bar acts as a wave filter and reduces shore erosion (lee effect). In contrast, nourishment on the beach face leads mostly to shore feeding and reconstruction (feeder effect). With successive nourishments, the beach face clearly becomes steeper and onshore sediment transport is reduced during moderate wave climates. The surface grain size analysis reveals marked variations. Coarser sediments are sorted on the bar and the upper beach face. These locations correspond to large wave dissipation zones during the storm apex.