ESR12 Adel Albaba

Research project description

Modelling the Mechanical Behaviour of Flexible Structures against Debris Flow

Fellow:                      Adel Albaba

Host Institutions:    IRSTEA and Grenoble Institute of Technology (INPG), Grenoble Supervisor:

Co-Supervisors:     Dr. François Nicot (IRSTEA), Dr Stephane Lambert (IRSTEA) and Dr Bruno Chareyre (INPG)

Debris flows are one of the most severe risks affecting mountainous areas. Strongly dictated by the weather conditions (storms, rainfalls), predicting the occurrence of such events and preventing their damage remain difficult tasks.

An innovative solution for debris flow mitigation consists of flexible structures, made up of wire nets, placed across sections of the torrent bed. Such open structures make water flows possible, but can control more viscous flows such as debris flows with a possible fraction of gravels or rocks.

The project focuses on the mechanical behaviour of such structures, by developing a numerical tool with engineering purposes. To this aim, discrete element method DEM is used (YADE open software), to describe both the debris flow and the barrier, starting with a rigid wall (Figure 1) which will be later replaced by ring nets, resulting a better understanding of their interaction. A specific attention is given to the modelling of debris flows, described as a saturated granular assembly. Recent developments carried out to model saturated granular materials with internal flows will be accounted for. Finally, comparisons with case studies will be done in order to validate the numerical tool, and practical recommendations (geometrical configuration, size, constitutive materials) will be drawn in order to optimize the resultant forces developed in the different parts of the structure.

The project strongly serves one of the important aims of MUMOLADE projects (Geohazards Mitigation). Furthermore, the project is well connected with ESR 12 where an experimental work is being carried out on scaled debris flow. Future cooperation is expected with ESR 9 and ESR 10 concerning the viscous behaviour of debris flow.

ESR12 Adel Albaba

ESR12 Adel Albaba