LARGE SCALE EXPERIMENTS ON BEACH EVOLUTION INDUCED BY BICHROMATIC WAVE GROUPS WITH VARYING GROUP PERIOD

Proceedings of the International Conference on Coastal Engineering

Ivan Caceres¹  Jan S. Ribberink⁴  Tom E. Baldock²  Joep van der Zanden⁴  Jose M Alsina³ 

[1] Universitat Politècnica de Catalunya;University of Queensland;Imperial College London;University of Twente

关键词: wave groups;    beach morphology;    bed level changes;    swash zone;    breaker bar location;   

DOI  :  10.9753/icce.v34.sediment.3

学科分类：建筑学

来源: Coastal Engineering Research Council

【 摘 要 】

New large scale experimental data have been presented showing the wave group influence on beach morphodynamics at the surf and swash zones. Bichromatic wave conditions were generated varying the modulation bandwidth but keeping the wave energetic content constant within the experimentation limits. The wave group influence in the surf zone is observed in the form of the cross-shore location of the breaker bar respect to the initial still water level (SWL) location, which has been shown to increase as increases the wave group period. This influence is explained in terms of differences on the surf zone width induced by the varying wave group periods. In the swash zone, time dependent bed level elevation measurements were done using a newly developed conductivity technique, the CCM+ system. Bed level time variations at the swash zone have shown to be composed of a long scale trend and bed level oscillations of shorter frequencies related to the wave group forcing. A good spectral correlation has been found between the water surface elevation and bed level variation at the wave group period for every bichromatic component indicating an important influence of wave groups on the swash zone morphodynamics.

【 授权许可】

Unknown