Built on Sand

Le livre Matière en Grains a été traduit et est disponible aux éditions MIT Press sous le titre Built on Sand – The Science of Granular Materials.

Granular matter—materials composed of vast amounts of solid grains—constitutes the most abundant form of matter on Earth. Granular materials assemble in disordered configurations scientists often liken to a bag of marbles. Made of macroscopic particles rather than molecules, they defy the standard scheme of classification in terms of solid, liquid, and gas. Avalanches, for example, can be characterized as friction, geometric congestion between grains. Granular materials provide a model for various domains, including engineering, physics, and biology, shedding light on collective behavior in disordered settings in general. William Blake famously wished “To see a World in a Grain of Sand”; in this book, pioneering researchers in granular matter explain the science contained in a simple assembly of grains.

The authors begin by describing a single grain with its different origins, shapes and sizes, then examine grains in piled or stacked form. They explain the packing fraction of granular media, a crucial issue that bears on the properties displayed in practical applications, explore small-scale deformations in piles of disordered grains, with particular attention to friction, and present theories of various modes of disorder. Along the way, key concepts such as force chains, arching effects, wet grains, sticky contacts, and inertial effects are discussed. Drawing on recent numerical simulations as well as classical concepts developed in physics and mechanics, this book offers an accessible introduction to a rapidly developing field.

Du merveilleux caché dans le quotidien – La physique de l’élégance

C’est un sentiment que nous avons tous éprouvé : derrière les objets qui émaillent notre quotidien se cache une étrange beauté. Elle semble le fruit d’un ordre naturel ou voulu, d’une organisation sous-jacente, mais aussi d’une fonction que nous ne percevons pas toujours.

Dans ce livre largement illustré, les auteurs, physiciens à l’ESPCI-Paris (École supérieurede physique et de chimie industrielles de la ville de Paris), se proposent de réapprendre à voir le monde qui nous entoure, tout en révélant la science à l’œuvre. Des combles d’Azay-le-Rideau à la mousse de savon, en passant par la boulette de papier froissé et le pont de liane, les 35 thèmes traités ont tous un point commun : la merveilleuse élégance des formes.

Etienne Guyon a consacré plusieurs chapitres où l’élégance se construit dans la matière en grains, du chateau de sable jusqu’à la structure en béton. Une partie « du grain au verre » reprend de façon différente quelques thèmes abordés dans Matière en Grains.

Communiqué de presse et table des matières

Du merveilleux caché dans le quotidien, Étienne Guyon, José Bico, Étienne Reyssat, Benoît Roman, Edition Flammarion.


320 pages – 162 x 210 mm Couleur – Broché

EAN : 9782081350618

ISBN : 9782081350618


25-29/06/2018 ICAR 2018 à Bordeaux

ICAR 2018 Conference: 10th International Conference on Aeolian Research, 25-29 June 2018, Bordeaux, France.

ICAR is an international conference dedicated to aeolian erosion and transport phenomena. Its 10th edition is to be held in Bordeaux from the 25th to the 29th of June, 2018. This cycle of conferences is sponsored by the International Society of Aeolian Research (ISAR), a non-profit association promoting research on aeolian processes, landforms and modelling, and editing the journal `Aeolian Research’ (www.aeolianresearch.org).


The conference covers a wide spectrum of all current research topics in aeolian science, and will include the following sessions:
1. Dunes and bedforms
conveners: M. Baddock, R. Ewing, L. Ping
2. Dust dynamics and processes
conveners: M. Klose, J.-B. Stuut
3. Modelling and numerical simulations
conveners: J. Nield, A. Valance
4. Paleo-environments
conveners: J. Roskin, A. Stone
5. Planetary aeolian research
conveners: J. Radebaugh, S. Silvestro
6. Experiments and instrumentation
conveners: M. Louge, G. Wiggs
7. Aerodynamics and sediment transport
conveners: C. McKenna-Neuman, H. Yizhaq
8. Coastal environments
conveners: P. Hesp, D. Jackson
9. Anthropogenic interactions
conveners: J. Leys, G. Sterk
10. Interaction with vegetation
conveners: J. Gillies, G. Okin

8-13/04/2018 EGU à Vienne

Conférence EGU (European Geosciences Union) à Vienne en Autriche du 8 au 13 avril 2018.

Session The importance of granular processes and segregation in geophysical flows: implications for landscape evolution and hazard analysis

co-organized by Philippe Frey (Grenoble), Nico Gray (Manchester) and Alexandre Valance (Rennes) at the forthcoming EGU General Assembly taking place in April, 8-13, 2018 in Vienna, Austria.

The deadline for the receipt of abstracts is 10 Jan 2018, 13:00 CET

Abstract for the session:

Modelling of Earth and planetary surface processes from channel dynamics to erosion of landscapes has made good use of the continuum framework, rather than directly dealing with particle scale processes, partly because of the typical large scale of the problem. Experiments, field observations, and modelling have shown the dynamics of discrete particle interactions, sometimes referred to as ‘granular physics’, plays an important role in erosion, transport, deposition and more generally in the evolution of landscapes and hazard analysis.
In particular, segregation by size, density and other properties largely modifies fluxes and results in complex patterns observed in many geophysical flows and landscapes. Examples include in fluvial geomorphology, armouring, downstream fining and drastic change in bedload and suspended sediment transport ; in debris flows, the coarsening of the front and levees ; and in Aeolian transport the internal structure of dune fields. Segregation also plays a role in hazards associated with snow avalanches, pyroclastic flows, rock avalanches, gravity currents and other geomorphic flows.
This session welcomes experimental, theoretical, numerical and field-based contributions within different environments, including coasts, estuaries, rivers, mountains enhancing our understanding of granular processes as well as their upscaling into continuum-like frameworks able of representing large-scale systems.