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This project investigated the potential of mangroves of modest cross-shore thickness to attenuate wave heights and reduce loads on sheltered structures through a prototype-scale physical model. Two forest densities and a baseline case were considered, and transient, regular, and irregular waves generated over the 18 m mangrove test section. Water surface elevations seaward, throughout, and leeward of the mangrove forest were measured, as well as pressures on a test wall positioned behind the forest test section.
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Prototype-scale laboratory observations of wave force reduction by an idealized mangrove forest of moderate cross-shore width
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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- PAR ID:
- 10574079
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Ocean Engineering
- Volume:
- 310
- Issue:
- P2
- ISSN:
- 0029-8018
- Page Range / eLocation ID:
- 118740
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.oceaneng.2024.118740
