The 3rd edition of the GéoMécanique newsletter is brought to you by Chao Yuan. It contains the latest news regarding research publications, conference visits and other activities of the staff and students from the GéoMécanique group of Laboratoire 3SR (Sols, Solides, Structures – Risques). If you have something you want to share, please don’t hesitate to contact us at: geomecanique.newsletter@3sr-grenoble.fr. Please feel free to forward the letter to colleagues and friends, and let them know that they can subscribe by themselves here. Enjoy.
Miscellaneous
Members of 3SR lab. and Geomechanics group were invited on Thursday 21 May in Vercors mountain by their colleagues from IRSTEA (National Research Institute of Science and Technology for Environment and Agriculture) working in the fields of gravity-related phenomena (avalanches, torrential floods, rock falls, dyke or dam bursts) and performance and risks of hydraulic structures and/or protection. Pascal, Gaël, Ghonwa, Patrizia, Viviana, Moustafa, Stiven and Albert presented the activities of 3SR and Geomechanics group in relation with IRSTEA. Interactions with colleagues from IRSTEA were very interesting. Even if many collaborations already exist with IRSTEA, we should still develop them (geosynthetics, FEMxDEM on snow, fluid-solid interactions in soils, …)
Recent results on localized fluidization of an injected granular layer are shown in the video of this month. The top part shows the changes of porosity as the injected flux is increased (the fluid is injected below the layer), suggesting bubbling phenomena in grain-fluid systems. At the bottom: the evolution of the inlet pressure, showing a marked peak as the flux is increased. The results compare quite well with some experiments done at Irstea (Pierre Philippe). They have been obtained by Eduard Puid-Montella (MSc, supervised by Bruno Chareyre and Luc Sibille), following the preliminary steps of Marcella Toraldo on the same topic.
A PhD position (starting in September 2015) is available at Laboratoire 3SR, University of Grenoble (France) on experimental mechanics of granular materials. The title of the project is “Force Inferred from macroscopic loading and grain motions” — further details are provided in the pdf file. Interested applicants should send a CV as well as a cover letter and one (or more) recommendation letter(s) to <Vincent.Richefeu@3sr-grenoble.fr> and <Jean-Noel.Roux@ifsttar.fr>. The deadline for applying is June 25, 2015.
Publications
The paper by Alessandro Tengattini and Edward Andò entitled “Kalisphera: an analytical tool to reproduce the partial volume effect of spheres imaged in 3D” has been accepted for publication in IOP’s Measurement Science and Technology.
The paper “Shear bands as bottlenecks in force transmission” has been just accepted for publication in EPL (Europhysics Letters). In this paper, co-authored by Eddy Andò and Cino Viggiani of 3SR plus a number of colleagues including Antoinette Tordesillas of Melbourne University, we construct a network flow model of force transmission to identify the bottlenecks in the contact networks of dense granular media.
Research projects
The final meeting of the C2D2 program (Concevoir et Construire pour le Développement Durable) was organized on June 3th by the french ministry of Environment and Energy and the RGC&U network. Bruno Chareyre presented the final report of the project “Hydrofond”, funded by the C2D2 program and focused on the hydromechanics of submerged foundations. The research has been done in a collaboration between 3SR and LEGI (Grenoble INP), Artelia consutling group, and LAMI (Univ. Clermont Ferrand).
Visits and conferences
Viviana Bonilla-Sierra, Frédéric Donzé, Timos Papachristos, Alexandra Tsopela and Luc Scholtès have participated in the 13th ISRM Congress 2015 – International Symposium on Rock Mechanics, held in Montréal, Québec, Canada from May 10 to 13. Timos presented his work titled “Hydraulic fracturation simulated by a 3D coupled HM-DEM model” in the Shale Symposium. Viviana talked about “A DEM analysis of rock slope stability in presence of a non-persistent joint” in the Slope Stability, Landslides and Surface Mining Session. Luc (our former PhD student) deliveded Jérôme Duriez’s (also our former PhD student) presentation titled “Discrete modeling of rock fracturing for various modes and mechanical properties”.
Viviana, Frédéric, Timos, Alexandra and Luc in 13th ISRM Congress, Montréal, Canada