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This paper describes 2-D numerical simulations aiming to reproduce the pressure impulse named confined-crest impact (Castellino et al., 2018), which occurs when a recurved parapet wall and non-breaking wave conditions are interacting. The simulations are carried out by using the IH2VOF and IHFOAM, the latter developed as OpenFOAM additional library. The results show a large increase of the pressures and forces value when the recurved part of the vertical parapet results completely occluded by the non-breaking wave crest. A sensitivity analysis has been carried out to study the influence of the geometrical parameters (radius r and opening angle a). It has been found a low variability with respect to the radius increase (from 1.0 m to 2.0 m) and a higher influence related to the opening angle variation. Finally, the non-dimensional force component has been represented as a function of the hydraulic and geometrical parameters by means of the dimensionless product (l/h)*s. These parameters represent the overhang extension seaward of the parapet, the water depth and the wave steepness with reference to deep-water conditions.

Floods can transport debris of a very wide range of dimensions, from cohesive sediments to large floating debris, such as trees and cars. The latter increases the risk associated with floods by, for example, obstructing the flow or damaging structures due to impact. The transport of this type of debris and their interaction with structures are often studied experimentally in the context of tsunamis and flash floods. Numerical studies on this problem are rare, therefore the present study focuses on the numerical modelling of the flow-debris interaction. This is achieved by simulating multiple laboratory experiments, available in the literature, of a single buoyant container transported by a dam-break flow in order to validate the chosen numerical approach. The numerical simulations are carried using the open source DualSPHysics model based on the smoothed particle hydrodynamics method coupled with the multi-physics engine CHRONO, which handles the container–bottom interactions. The trajectory, as well as the velocity of the centroid of the container, were tracked throughout the simulation and compared with the same quantities measured in the laboratory. The agreement between the model and the experiment results is quantitatively assessed using the normalised root mean squared error and it is shown that the model is accurate in reproducing the floating container trajectory and velocity.

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