Publications

2011

• Modeling radiation effects on the fracture process in simplified nuclear glass
  
  • Kieu Le-Hai
  • Delaye Jean-Marc
  • Stolz Claude
  , 2011.
• Minimal Integer Automaton behind Crystal Plasticity
  
  • Salman Umut
  • Truskinovsky Lev
  Physical Review Letters, American Physical Society, 2011, 106, pp.175503. Power law fluctuations and scale-free spatial patterns are known to characterize steady state plastic flow in crystalline materials. In this Letter we study the emergence of correlations in a simple Frenkel-Kontorova-type model of 2D plasticity which is largely free of arbitrariness, amenable to analytical study, and is capable of generating critical exponents matching experiments. Our main observation concerns the possibility to reduce continuum plasticity to an integer-valued automaton revealing inherent discreteness of the plastic flow. (10.1103/PhysRevLett.106.175503)
  DOI : 10.1103/PhysRevLett.106.175503
• Experimental investigation of the delayed behaviour of unsaturated argillaceous rocks by means of Digital Image Correlation techniques
  
  • Yang Diansen
  • Bornert Michel
  • Chanchole Serge
  • Wang Linlin
  • Valli Pierre
  • Gatmiri Behrouz
  Applied Clay Science, Elsevier, 2011, 54 (1), pp.53-62. We present an experimental study on the delayed behavior of unsaturated argillaceous rocks, including shrinkage, swelling, and creep, by means of Digital Image Correlation (DIC) techniques. In order to measure the very low strain rate of the argillaceous rocks at various scales (100 μm-cm) under uniaxial compression and various environmental conditions, a specific optimized optical setup was used. The natural argillaceous rocks were hydrated or dehydrated by controlling the ambient humidity around the samples, and the obtained unsaturated samples were then subjected to creep tests at different stress levels. The mechanical response to hydration and dehydration strongly depended on the mechanical loading, which induced an additional deformation. During creep, the strain rate increased when the moisture or the applied stress increased. The strain rate at a relative humidity of 75% was about one order of magnitude larger than at a dried state (relative humidity = 25%). The anisotropy of the strain induced by the moisture and mechanical loading was enhanced over time. The time dependent behavior as observed at different scales (100 μm-cm) is discussed. (10.1016/j.clay.2011.07.012)
  DOI : 10.1016/j.clay.2011.07.012
• Twelve-year monitoring of the idle Etrez salt cavern
  
  • Berest Pierre
  • Bérest P.
  • Brouard Benoît
  • Hévin Grégoire
  International Journal of Rock Mechanics and Mining Sciences, Pergamon and Elsevier, 2011, Volume 48 (1), pp.168-173. (10.1016/j.ijrmms.2010.07.004)
  DOI : 10.1016/j.ijrmms.2010.07.004
• Variational Principles in the Theory of Gradient Plasticity
  
  • Nguyen Quoc Son
  Comptes Rendus. Mécanique, Académie des sciences (Paris), 2011, 000 (000), pp.000. Gradient models have been intensively discussed in the literature for the study of time- dependent or time-independent processes such as visco-plasticity, plasticity and damage. This paper is devoted to the theory of Gradient Plasticity. A general and consistent math- ematical description available for common time-independent behaviours is presented. Our attention is focussed on the derivation of general results such as the description of the gov- erning equations for the global response, for the rate response, the expression of the associ- ated variational principles and the question of uniquenness in terms of the energy potential ́ and the dissipation potential. (10.1016/j.crme.2011.08.002)
  DOI : 10.1016/j.crme.2011.08.002
• Multiscale viscoplastic behaviour of halite : micromechanical approaches by full field measurements
  
  • Bourcier M.
  • Dimanov A.
  • Bornert Michel
  • Héripré E.
  • Charrier B.
  • Ludwig Wolfgang
  • Raphanel J. L.
  , 2011.
• Advances in the constitutive equation parameter identification procedure why experiments should discuss with numerical simulations
  
  • Crépin Jérôme
  • Geoffroy Dominique
  • Héripré Eva
  • Roos Arjen
  , 2011.
• Newtonian flow of heterogeneous synthetic gabbros at high strain: Grain sliding, ductile failure, and contrasting local mechanisms and interactions
  
  • Dimanov Alexandre
  • Dresen Georg
  • Raphanel J.
  European Journal of Mineralogy, Copernicus, 2011, Volume: 23 (Issue: 3), pp.Pages: 303−322. (10.1127/0935-1221/2011/0023-2110)
  DOI : 10.1127/0935-1221/2011/0023-2110
• The effective behavior of elastic bodies containing microcracks or microholes localized on a surface
  
  • Marigo Jean-Jacques
  • Pideri Catherine
  International Journal of Damage Mechanics, SAGE Publications, 2011, 20 (Special issue of ESMC2009), pp.pages 1151-1177. We propose a two-scale method to find the effective behavior of a three-dimensional linear elastic medium containing a series of microcracks or microholes located on a surface. The obtained effective behavior is that of a homogeneous body with, in place of the actual microdefects, a surface across which the displacements and the stresses suffer jump discontinuities. The transmission conditions are in general of Ventcel's type. The coefficients entering in these jump conditions are obtained by solving six elastic problems posed on an infinite representative cell. The theoretical analysis is illustrated by a few examples. (10.1177/1056789511406914)
  DOI : 10.1177/1056789511406914
• A computational approach for the fatigue design of threaded connections
  
  • Ferjani Mohamed
  • Averbuch Daniel
  • Constantinescu Andrei
  International Journal of Fatigue, Elsevier, 2011, 33, pp.pp. 610-623. The aim of this paper is to propose a lifetime prediction method for threaded connections. The example discussed here is a drillstring connection used in the oil and gas industry. The method is based on a mechanical analysis performed either with finite elements or a closed-form solution described in a companion paper, and a fatigue analysis using the Dang Van criterion which has been extended to finite life domain. The mechanical analysis provides the stabilized stress path and the fatigue analysis provides the fatigue life. Fatigue tests have been performed on small scale threaded connections in order to validate the methodology. The comparisons with the predictions show the difficulties to estimate the fatigue life on structures presenting high stress gradient due to scale effects. (10.1016/j.ijfatigue.2010.11.006)
  DOI : 10.1016/j.ijfatigue.2010.11.006
• Simulation of simplified nuclear glass fracture by molecular dynamics
  
  • Kieu Le-Hai
  • Delaye Jean-Marc
  • Stolz Claude
  , 2011.
• Punch Indentation of Polyurea at Different Velocities: Experiments and Simulations
  
  • Shim J.
  • Mohr Dirk
  Mechanics of Materials, Elsevier, 2011, pp.349-360.
• Effect of Stress Triaxiality and Lode Angle on the Kinetics of Strain-induced Austenite-to-Martensite Transformation
  
  • Beese A.M.
  • Mohr Dirk
  Acta Materialia, Elsevier, 2011, pp.2589-2600.
• The air-liquid flow in a microfluidic airway tree
  
  • Song Yu
  • Baudoin Michael
  • Manneville Paul
  • Baroud Charles N.
  Medical Engineering & Physics, Elsevier, 2011, 33 (7), pp.849-856. Microfluidic techniques are employed to investigate air-liquid flows in the lung. A network of microchannels with five generations is made and used as a simplified model of a section of the pulmonary airway tree. Liquid plugs are injected into the network and pushed by a flow of air; they divide at every bifurcation until they reach the exits of the network. A resistance, associated with the presence of one plug in a given generation, is defined to establish a linear relation between the driving pressure and the total flow rate in the network. Based on this resistance, good predictions are obtained for the flow of two successive plugs in different generations. The total flow rate of a two-plug flow is found to depend not only on the driving pressure and lengths of the plugs, but also the initial distance between them. Furthermore, long range interactions between daughters of a dividing plug are observed and discussed, particularly when the plugs are flowing through the bifurcations. These interactions lead to different flow patterns for different forcing conditions: the flow develops symmetrically when subjected to constant pressure or high flow rate forcing, while a low flow rate driving yields an asymmetric flow. Copyright © 2010 IPEM. Published by Elsevier Ltd (10.1016/j.medengphy.2010.10.001)
  DOI : 10.1016/j.medengphy.2010.10.001
• Legendre-Fenchel duality in elasticity
  
  • Ciarlet Philippe G.
  • Geymonat Giuseppe
  • Krasucki Françoise
  Comptes rendus de l'Académie des sciences. Série I, Mathématique, Elsevier, 2011, 349, pp.597-602. We show that the displacement and strain formulations of the displacement-traction problem of three-dimensional linearized elasticity can be viewed as Legendre-Fenchel dual problems to the stress formulation of the same problem. We also show that each corresponding Lagrangian has a saddle-point, thus fully justifying this new approach to elasticity by means of Legendre-Fenchel duality. (10.1016/j.crma.2011.03.007)
  DOI : 10.1016/j.crma.2011.03.007
• Integrative Mechanobiology of Growth and Architectural Development in Changing Mechanical Environments
  
  • Moulia Bruno B.
  • Der Loughian Christelle C.
  • Bastien Renaud
  • Martin O.
  • Rodriguez M.
  • Gourcilleau Delphine
  • Barbacci A.
  • Badel Eric
  • Franchel G.
  • Lenne C.
  • Roeckel-Drevet Patricia P.
  • Allain Jean-Marc
  • Frachisse J. M.
  • de Langre Emmanuel
  • Coutand Catherine
  • Fournier-Leblanc Nathalie
  • Julien Jean-Louis J.-L.
  , 2011, 9, pp.269-302. Mechanosensitive control of plant growth is a major process shaping how terrestrial plants acclimate to the mechanical challenges set by wind, self-weight, and autostresses. Loads acting on the plant are distributed down to the tissues, following continuum mechanics. Mechanosensing, though, occurs within the cell, building up into integrated signals; yet the reviews on mechanosensing tend to address macroscopic and molecular responses, ignoring the biomechanical aspects of load distribution to tissues and reducing biological signal integration to a "mean plant cell." In this chapter, load distribution and biological signal integration are analyzed directly. The Sum of Strain Sensing model S 3 m is then discussed as a synthesis of the state of the art in quantitative deterministic knowledge and as a template for the development of an integrative and system mechanobiology. (10.1007/978-3-642-19091-9_11)
  DOI : 10.1007/978-3-642-19091-9_11
• Semianalytical solution for the stress distribution in notched tubes
  
  • Ferjani Mohamed
  • Averbuch Daniel
  • Constantinescu Andrei
  International Journal of Fatigue, Elsevier, 2011, 33, pp.pp. 557-567. The aim of this paper is to present an alternative solution to the finite element method for the determination of the elastic stress field for an axi-symmetric notched tube under tension and bending loadings. The proposed solution is an extension of the work of Filippi and Lazzarin (2004) [8] to tubular specimens. It provides the stress field distribution along the notch bisector. A good agreement was found between the solution proposed in the present paper and the results from a finite element analysis. A sensitivity analysis is performed to establish the domain of validity of the solution with respect to the dimensions of the notched tube. (10.1016/j.ijfatigue.2010.10.009)
  DOI : 10.1016/j.ijfatigue.2010.10.009
• Hydromechanical behavior of heterogeneous carbonate rock under proportional triaxial loadings
  
  • Dimanov Alexandre
  • Dautriat Jérémie
  • Gland N.
  • Raphanel J.
  Journal of Geophysical Research, American Geophysical Union, 2011, 116 (B01205), pp.DOI: 10.1029/2009JB000830. (10.1029/2009JB000830)
  DOI : 10.1029/2009JB000830
• In-situ X-ray microtomography characterization of damage in SiC/SiC minicomposites
  
  • Chateau Camille
  • Gélébart Lionel
  • Bornert Michel
  • Crépin Jérôme
  • Boller Elodie
  • Sauder C.
  • Ludwig Wolfgang
  Composites Science and Technology, Elsevier, 2011, 71 (6), pp.916-924. The purpose of the present study is to characterize matrix crack propagation and fiber breaking occurrences within SiC/SiC minicomposite in order to validate later on a multiscale damage model at the local scale. An in-situ X-ray microtomography tensile test was performed at the European Synchrotron Radiation Facility (ESRF, ID19 beamline) in order to obtain 3-dimensional (3D) images at six successive loading levels. Results reveal a slow and discontinuous propagation of matrix cracks, even after the occurrence of matrix crack saturation. A few fiber failures were also observed. However, radiographs of the whole length (14 mm) of the minicomposites under a load and after the failure were more appropriate to get statistical data about fiber breaking. Thus, observations before the ultimate failure revealed only a few fibers breaking homogenously along the minicomposite. In addition, an increase in fiber breaking density in the vicinity of the fatal matrix crack was observed after failure. These experimental results are discussed in regards to assumptions used in usual 1-dimensional (1D) models for minicomposites. (10.1016/j.compscitech.2011.02.008)
  DOI : 10.1016/j.compscitech.2011.02.008