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A copula-based model to describe the uncertainty of overtopping variables on mound breakwaters

Mares Nasarre, P. (author), van Gent, M.R.A. (author), Morales Napoles, O. (author)

Rising sea levels caused by climate change are increasing the risk of overtopping on coastal structures. Moreover, there is a growing societal concern about the visual impact of these structures, which leads to the lowering of their crest freeboards. In previous studies, safety during overtopping events was assessed considering the...

journal article 2024

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OpenFOAM design sensitivity analysis on a homogeneous low-crested structure with concrete elements seaward of a vertical seawall to reduce overtopping

Jonker, R. G. (author), AlYousif, A.Y. (author), Hofland, Bas (author), Antonini, A. (author), Zoon, Arthur (author), Smith, Gregory (author)

This study treats a detached homogenous low-crested structure (HLCS) made of Cubipod concrete elements placed seaward of a vertical wall (forming a basin in between) to reduce overtopping. Assessing the complex hydrodynamics and effects of changing the geometry of such a system in relation to overtopping reduction is challenging. The...

journal article 2024

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Non-Hydrostatic Modelling of Coastal Flooding in Port Environments

Suzuki, T. (author), Altomare, Corrado (author), Willems, Marc (author), Dan, Sebastian (author)

Understanding key flooding processes such as wave overtopping and overflow (i.e., water flows over a structure when the crest level of the structure is lower than the water level in front) is crucial for coastal management and coastal safety assessment. In port and harbour environments, waves are not only perpendicular to the coastal...

journal article 2023

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Wave overtopping layer thickness on the crest of rubble mound seawalls

Koosheh, Ali (author), Etemad-Shahidi, Amir (author), Cartwright, Nick (author), Tomlinson, Rodger (author), van Gent, M.R.A. (author)

During storms, ensuring the protection of people, vehicles and infrastructure on the crest of coastal structures from wave overtopping hazards is crucial. The thickness of the wave overtopping layer is a key variable used for assessing safety and maintaining a secure design. Traditionally, this parameter is associated with the height...

journal article 2023

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Numerical modelling of wave overtopping discharges at rubble mound breakwaters using OpenFOAM®

Mata, Marisol Irías (author), van Gent, M.R.A. (author)

Numerical modelling of wave interaction with rock-armoured rubble mound breakwaters has been performed to study wave overtopping. The influences of the slope angle, a berm in the seaward slope, a protruding crest wall, a recurved parapet, and the wave steepness have been studied using a validated CFD model (OpenFOAM). The numerical modelling...

journal article 2023

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Using salt marshes for coastal protection: Effective but hard to get where needed most

Marin-Diaz, Beatriz (author), van der Wal, Daphne (author), Kaptein, Leon (author), Martinez-Garcia, Pol (author), Lashley, Christopher H. (author), de Jong, Kornelis (author), Nieuwenhuis, Jan Willem (author), Govers, Laura L. (author), Olff, Han (author), Bouma, Tjeerd J. (author)

Salt marshes fronting coastal structures, such as seawalls and dikes, may offer important ecosystem-based coastal defence by reducing the wave loading and run-up levels during storms. We question (i) how the long-term salt marsh development in the Dutch Wadden Sea relates to the tidal-flat foreshore bathymetry and (ii) how the wave run-up...

journal article 2023

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Numerical investigation of the effects of roughness, a berm and oblique waves on wave overtopping processes at dikes

Chen, W. (author), Warmink, J.J. (author), van Gent, M.R.A. (author), Hulscher, S.J.M.H. (author)

The mean overtopping discharge and the overtopping flow parameters related to individual overtopping events are often used to characterize the wave overtopping processes at dikes. Roughness, berms and oblique waves have significant effects on the wave overtopping processes at dikes while these effects are still not fully understood. A 2DV...

journal article 2022

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Experimental study of wave overtopping at rubble mound seawalls

Koosheh, Ali (author), Etemad-Shahidi, Amir (author), Cartwright, Nick (author), Tomlinson, Rodger (author), van Gent, M.R.A. (author)

Seawalls play a significant role in protecting coastal areas against wave attack and flooding. The accurate estimation of wave overtopping at seawalls is therefore crucial to adequately protect people and infrastructure in these regions. In this study, the mean wave overtopping rate at rubble mound seawalls was investigated through 140 small...

journal article 2022

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Simulation of 3D overtopping flow–object–structure interaction with a calibration-based wave generation method with DualSPHysics and SWASH

Suzuki, T. (author), García-Feal, Orlando (author), Domínguez, José M. (author), Altomare, Corrado (author)

Ongoing climate change is a significant threat to coastal communities. To understand potential risks during extreme storm events, detailed post-overtopping processes are investigated using DualSPHysics and SWASH with a newly developed approach. It is a calibrated-based wave generation: a target incident wave is first obtained from the...

journal article 2022

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Distribution of individual wave overtopping volumes at rubble mound seawalls

Koosheh, Ali (author), Etemad-Shahidi, Amir (author), Cartwright, Nick (author), Tomlinson, Rodger (author), van Gent, M.R.A. (author)

For a safe design of a rubble mound seawall, overtopping characteristics such as the mean overtopping discharge (q) and the maximum individual overtopping volume (V_max) should be limited. Unlike q, the estimation of V_max is more complex and requires a wave-by-wave analysis of overtopping as well as a statistical analysis...

journal article 2022

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Wave overtopping discharges at rubble mound breakwaters including effects of a crest wall and a berm

van Gent, M.R.A. (author), Wolters, Guido (author), Capel, Alex (author)

Physical model tests have been performed to study wave overtopping at rubble mound breakwaters, including breakwaters with a crest wall, breakwaters with a berm, and breakwaters with a crest wall and a berm. For rubble mound structures with a protruding crest wall or with a stable berm, limited information is available in literature even...

journal article 2022

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Wave overtopping at near-vertical seawalls: Influence of foreshore evolution during storms

Briganti, Riccardo (author), Musumeci, Rosaria Ester (author), van der Meer, Jentsje (author), Romano, Alessandro (author), Stancanelli, L.M. (author), Kudella, Matthias (author), Akbar, Rizki (author), Altomare, Corrado (author), Suzuki, T. (author)

This work presents the results of an investigation on how wave overtopping at a near-vertical seawall at the back of a sandy foreshore is influenced by sequences of erosive storms. The experiments were carried out in the Large Wave Flume (GWK) at Leibniz University, Hannover (Germany). The tested layout consisted of a near-vertical 10/1...

journal article 2022

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On the mean overtopping rate of rubble mound structures

Etemad-Shahidi, Amir (author), Koosheh, Ali (author), van Gent, M.R.A. (author)

Estimation of the mean overtopping discharge is a major task in the design and assessment of the crest level of rubble mound structures such as breakwaters and seawalls. The tolerable mean overtopping rates are given based on the associated risk and wave characteristics. Several empirical formulas have been developed for the prediction of...

journal article 2022

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Overflow Tests on Grass-Covered Embankments at the Living Lab Hedwige-Prosperpolder: An Overview

Koelewijn, André R. (author), Rikkert, S.J.H. (author), Peeters, P. (author), Depreiter, Davy (author), van Damme, Myron (author), Zomer, Wouter (author)

In regions with a temperate climate, a well-maintained grass sod on a clay layer is considered a reliable protection for dams and dikes. In the Living Lab Hedwige-Prosperpolder, on the left bank of the Scheldt river straddling the border between Belgium and the Netherlands, a series of 27 overflow tests with a purpose-built overflow generator...

journal article 2022

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Wave overtopping predictions using an advanced machine learning technique

den Bieman, Joost P. (author), van Gent, M.R.A. (author), van den Boogaard, Henk F.P. (author)

Coastal structures are often designed to a maximum allowable wave overtopping discharge, hence accurate prediction of the amount of wave overtopping is an important issue. Both empirical formulae and neural networks are among the commonly used prediction tools. In this work, a new model for the prediction of mean wave overtopping discharge is...

journal article 2021

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Field measurements of very oblique wave run-up and overtopping with laser scanners

Oosterlo, P. (author), Hofland, Bas (author), van der Meer, J.W. (author), Overduin, Maarten (author), Steendam, Gosse Jan (author)

This paper presents the first field measurements with an innovative laser scanner system, during an actual severe winter storm with very oblique wave attack. The goal of this paper is to validate this innovative system for measuring wave run-up and wave overtopping parameters during storms with very oblique wave attack. The paper describes the...

journal article 2021

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Calibration and preparation of field measurements of oblique wave run-up and overtopping on dikes using laser scanners

Oosterlo, P. (author), Hofland, Bas (author), van der Meer, J.W. (author), Overduin, Maarten (author), Steendam, Gosse Jan (author)

Wave overtopping is typically measured in the field using overtopping tanks. In this paper, an alternative system is developed that uses two laser scanners. The system also measures wave run-up, as well as run-up depths and velocities, both during perpendicular and oblique waves on a dike in the field. The paper considers the first calibration...

journal article 2021

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Formulating Wave Overtopping at Vertical and Sloping Structures with Shallow Foreshores Using Deep-Water Wave Characteristics

Lashley, Christopher H. (author), Van Der Meer, Jentsje (author), Bricker, J.D. (author), Altomare, Corrado (author), Suzuki, T. (author), Hirayama, Katsuya (author)

The state-of-The-Art formulas for mean wave overtopping (q) assessment typically require wave conditions at the toe of the structure as input. However, for structures built either on land or in very shallow water, obtaining accurate estimates of wave height and period at the structure toe often proves difficult and requires the use of either...

journal article 2021

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Influence of oblique wave attack on wave overtopping at caisson breakwaters with sea and swell conditions

van Gent, M.R.A. (author)

The amount of wave overtopping at coastal structures such as vertical caisson breakwaters is strongly dependent on the angle of wave attack. The reducing effects of oblique waves on wave overtopping compared to perpendicular wave attack has been studied by means of three-dimensional wave basin tests. In these physical model tests the caisson...

journal article 2021

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Wave overtopping discharge for very gently sloping foreshores

Nguyên, Hà (author), Hofland, Bas (author), Chinh, Vu Dan (author), Stive, M.J.F. (author)

The spectral wave period T_m-1,0 at the toe of sea-dikes is a crucial parameter to predict wave overtopping discharge over sea-dikes. It is known from literature that this period quickly increases when waves reach shallow foreshores; however, sometimes the assumption is made that the wave period remains constant from offshore to...

journal article 2020