DURCWAVE ‘amending the Design criteria of URban defences in LECZs through Composite-modelling of WAVE overtopping under climate change scenarios’

The main scientific objective of DURCWAVE project is to define new design criteria for wave action by modelling wave overtopping and post-overtopping processes of these urban defences.Postprint (published version

Overtopping formula for vertical tiers-headed breakwaters

The semi-empirical methods are useful tools to understand the wave overtopping phenomena, but uncertainty remains on their applicability. It’s necessary to carry out campaign surveys or laboratory tests to support them. In this paper we apply the methods proposed in the European Overtopping Manual (2007) in order to assess the flows over a vertical breakwater, marking the need to calibrate those methodologies to take into account the peculiar geometry of the structural system. This was done by introducing appropriate correction factors. The results show an improved accuracy, among numerical results and physical ones.Postprint (published version

Characterization of overtopping waves on sea dikes with gentle and shallow foreshores

Due to ongoing climate change, overtopping risk is increasing. In order to have effective countermeasures, it is useful to understand overtopping processes in details. In this study overtopping flow on a dike with gentle and shallow foreshores are investigated using a non-hydrostatic wave-flow model, SWASH (an acronym of Simulating WAves till SHore). The SWASH model in 2DV (i.e., flume like configuration) is first validated using the data of long crested wave cases with second order wave generation in the physical model test conducted. After that it is used to produce overtopping flow in different wave conditions and bathymetries. The results indicated that the overtopping risk is better characterized by the time dependent h (overtopping flow depth) and u (overtopping flow velocity) instead of hmax (maximum overtopping flow depth) and umax (maximum overtopping flow velocity), which led to overestimation of the risk. The time dependent u and h are strongly influenced by the dike configuration, namely by the promenade width and the existence of a vertical wall on the promenade: the simulation shows that the vertical wall induces seaward velocity on the dike which might be an extra risk during extreme events.This research was part of the CREST (Climate REsilient CoaST) project (http://www.crestproject.be/en), funded by the Flemish Agency for Innovation by Science and Technology, grant number 150028. Corrado Altomare acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No.: 792370.Peer ReviewedPostprint (published version

Simulation of random wave overtopping by a WCSPH model

In this work the Weakly Compressible SPH-based (WCSPH) model DualSPHysics has been validated and applied to study the random wave overtopping of dike-promenade layout in shallow water conditions. Data from physical model tests carried out in a small-scale wave flume have been used for model validation. The results have been compared in terms of water surface elevation, mean discharges and individual overtopping volumes distribution. The selected geometrical layout is representative of the coastal area of Premià de Mar, in Catalonia (Spain). This stretch of the coast presents both railways and a bike path very close to the shore and therefore exposed to possible sea storms. For the first time an SPH-based model has been employed to reproduce long-lasting wave overtopping tests, made of time series of 1000 irregular waves, which are representative of real sea states. The density diffusion scheme and the modified Dynamic Boundary Conditions have been applied in the present simulations. By employing standard setup for SPH modelling of wave-structure interaction problems of a very long duration, stable simulations and accurate results have been attained