Physical Modeling of Wave Height Attenuation through Flexible Vegetation
Publication: Leveraging Sustainable Infrastructure for Resilient Communities
ABSTRACT
About 40% of the world’s population lives within 100 km of the coast and is threatened by sea level rise and extreme weather events associated with increasing global temperatures and climate change. These hazards exacerbate the vulnerability of coastal communities to shoreline erosion and damage by waves and flooding. This project focused on the effectiveness of flexible vegetation as a noninvasive, sustainable, and resilient shoreline protection alternative. An idealized physical model was designed and constructed in a wave flume. Water surface elevations were measured seaward and leeward of the vegetation and a baseline case subjected to multiple wave conditions at two different water depths, to assess the effect of vegetation emergence or submergence on wave attenuation. Considering significant wave heights, transmission coefficients ranged from 0.32 to 0.39 and 0.73 to 0.90 for emergent and submerged conditions, respectively. Considering mean wave heights, transmission coefficients ranged from 0.60 to 0.70 and 0.82 to 0.91 for emergent and submerged conditions, respectively. Emergent vegetation resulted in smaller transmission coefficients (greater wave height attenuation) due to interruption of the entire wave profile.
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Leveraging Sustainable Infrastructure for Resilient Communities
Pages: 91 - 101
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Published online: Jan 20, 2022
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