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A prototype-scale physical model was used to study wave height attenuation through an idealized mangrove forest and the resulting reduction of wave forces and pressures on a vertical wall. An 18 m transect of a Rhizophora forest was constructed using artificial trees, considering a baseline and two mangrove stem density configurations. Wave heights seaward, throughout, and shoreward of the forest and pressures on a vertical wall landward of the forest were measured. Mangroves reduced wave-induced forces by 4%–43% for random waves and 2%–38% for regular waves. For nonbreaking wave cases, the shape of the pressure distribution was consistent, implying that the presence of the forest did not change wave-structure interaction processes. Analytical methods for determining nonbreaking wave-induced loads provided good estimations of measured values when attenuated wave heights were used in equations. The ratio of negative to positive force ranged between 0.14 and 1.04 for regular waves and 0.31 to 1.19 for random waves, indicating that seaward forces can be significant and may contribute to destabilization of seawalls during large storms. These results improve the understanding of wave-vegetation-structure interaction and inform future engineering guidelines for calculating expected design load reductions on structures sheltered by emergent vegetation.
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An Experimental and Analytical Study on Wave-Structure Interaction
Coastal regions host significantly higher population densities compared to inland areas, and coastal communities are at risk for damage due to wave forces during hurricane or storm events. To better understand wave-structure interaction for the robust design of coastal structures, a physical model was constructed and tested to measure wave-induced pressures on three vertical walls with varying widths. Forces determined by integrating measured pressures over the face of each wall were compared with existing analytical formulations for determining wave forces on walls. Results indicate that blockage, the term used to account for the ratio of the wall area to the cross-sectional flow area, influences the wave forces experienced by a wall and that this factor is not accounted for in certain contemporary models.
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- Award ID(s):
- 2110262
- PAR ID:
- 10574106
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-6809-1
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Location:
- Hampton Roads, VA, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/OCEANS47191.2022.9977215
