Green-gray connections: Coupled equations of wave attenuation and structural response for engineering design of hybrid infrastructure

IF 4.5 2区工程技术 Q1 ENGINEERING, CIVIL

Coastal Engineering Pub Date : 2025-09-15 DOI:10.1016/j.coastaleng.2025.104877

Margaret Libby , Tori Tomiczek , Daniel T. Cox , Pedro Lomónaco

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引用次数: 0

Abstract

A quantitative method is proposed for predicting the engineering performance of a hybrid green-gray system comprised of a mangrove forest seaward of a conventional engineered structure to mitigate wave action. The method coupled existing empirical equations to (1) predict the wave height attenuation of random waves transmitted through the mangrove forest and (2) use the resulting significant wave height as input to existing equations to estimate wave overtopping on a vertical wall or rubble-mound revetment or wave force on a vertical wall. The predicted wave height attenuation was parameterized by a drag coefficient obtained from an empirical relation developed from previous laboratory results. The method was validated with data from two large-scale wave flume studies of wave overtopping and wave force, which used similar model mangroves at 1:2 and 1:1 scale, respectively. The method conservatively predicted the overtopping of a vertical wall or rubble-mound revetment within a factor of 1.7 for discharge rates greater than 1 × 10⁻³ m³/s/m and a factor of 3.5 for discharge rates greater than 1 × 10⁻⁴ m³/s/m. The predictions of wave forces were also conservative and were within a factor of 1.3 compared to the measurements. The overprediction of the wave force increased slightly with mangrove forest density, indicating a possible interaction between the waves and the green and gray features that reduced the wave forces more than expected from the wave attenuation alone. The apparent interaction was small, and the results of the proposed method were reasonable compared to the observations. The present results show promise for a design approach which assumes independent performance of the components to motivate a calculation coupling empirical equations to estimate the performance of hybrid green-gray systems for coastal defenses. Future study is necessary to parameterize wave attenuation by natural mangrove forests and to account for nonlinear processes such as wave breaking and wave-induced setup.

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绿灰连接：混合基础设施工程设计中波浪衰减与结构响应的耦合方程

提出了一种定量的方法来预测一个由红树林组成的混合绿灰系统的工程性能，以减轻波浪作用的传统工程结构。该方法将现有经验方程耦合到(1)预测通过红树林传播的随机波的波高衰减；(2)将得到的显著波高作为现有方程的输入，以估计垂直墙或碎石丘护岸上的波浪过顶或垂直墙上的波浪力。预测的波高衰减由阻力系数参数化，阻力系数是从以前的实验室结果中得到的经验关系。该方法通过两个大型波浪水槽研究的数据进行了验证，这两个研究分别使用了1:2和1:1比例的类似模型红树林。对于流量大于1 × 10−3 m3/s/m的垂直墙或碎石丘护岸，该方法的保守预测因子为1.7；对于流量大于1 × 10−4 m3/s/m的护岸，该方法的保守预测因子为3.5。波浪力的预测也是保守的，与测量结果相比，误差在1.3倍以内。随着红树林密度的增加，对波浪力的过度预测略有增加，这表明波浪与绿色和灰色特征之间可能存在相互作用，这种相互作用比仅从波浪衰减中预期的更能降低波浪力。表观相互作用较小，所得结果与观测结果比较合理。目前的结果表明，一种假设组件独立性能的设计方法有望激发计算耦合经验方程来估计海防混合绿灰系统的性能。未来的研究需要对天然红树林的波浪衰减进行参数化，并考虑波浪破碎和波浪诱导建立等非线性过程。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Coastal Engineering 工程技术-工程：大洋

CiteScore

9.20

自引率

13.60%

发文量

审稿时长

3.5 months

期刊介绍： Coastal Engineering is an international medium for coastal engineers and scientists. Combining practical applications with modern technological and scientific approaches, such as mathematical and numerical modelling, laboratory and field observations and experiments, it publishes fundamental studies as well as case studies on the following aspects of coastal, harbour and offshore engineering: waves, currents and sediment transport; coastal, estuarine and offshore morphology; technical and functional design of coastal and harbour structures; morphological and environmental impact of coastal, harbour and offshore structures.