INFLUENCE OF NEARSHORE BERM ON BEACH NOURISHMENT

[摘要] The influence of a large (3.0x106 m3) nearshore berm on a large (4.1xl06 m3) beach nourishment project at Perdido Key, FL, is addressed via a monochromatic, numerical wave transformation model. Two years of post-placement survey data indicate that the nearshore berm, placed at a depth of 6 m with a relief of 1-1/2 m, did not migrate during this time period. Wave model results suggest that the berm influences the beach nourishment project via refraction, but breaking and diffraction effects are not significant. The berm causes wave transformation and leads to zones of wave energy focusing (and corresponding de-focusing) that affect longshore sediment transport rates in the lee of the berm. For a typical wave condition, predicted high-energy regions correlate well with observed erosional areas. The findings indicate the relative importance of project-induced wave transformation that should be considered during the design process for nearshore berm projects.

[学科分类] 建筑学

[关键词] beach nourishment;nearshore berm