In the current context of climate change and ageing infrastructures, breaching of earthen embankments becomes a major issue for many cities and countries. It is well known that overtopping during floods is one of the main causes of breaching leading to devastating floods. The first intent of this thesis is to propose and conceptualize a holistic modelling approach of the dike breaching process by overtopping. Starting from observations of the process in the field and in laboratory experiments, the main physical mechanisms involved were identified. Sediment transport, surface-subsurface flow interaction, effect of suction pressure on the material’s strength, and large deformations of the dike structure were recognized as key processes.

The thesis results in a numerical framework for modelling dike breaching under overtopping conditions, explicitly capturing the interaction between hydraulic flow, water infiltration, and geomechanical failure. The model combines state-of-the-art hydraulic and sediment transport formulations with an advanced unsaturated soil mechanics framework that accounts for large deformations and high-order continuum theory, providing a advanced level of physical realism for dike failure simulations.

Membres du jury :

• Prof. Sandra Soares-Frazão (UCLouvain)(Promoteur)

• Prof. Hadrien Rattez (UCLouvain)(Promoteur)

• Prof. Grégoire Winckelmans (UCLouvain) (Président)

• Prof. Mathieu Javaux (UCLouvain) (Secrétaire)

• Prof. Frédéric Collin (ULIège) 

• Prof. Daniel Caviedes-Voullième (Forschungszentrum Jülich, TU Dresden)

Soutenance accessible par Teams : https://teams.microsoft.com/meet/38232123067278?p=FDA7I5jFgHLaPQU2bX