Publications

2001

• sur les mécanismes de la plasticité et de l'endommagement
  
  • Berveiller M.
  • Bretheau T.
  • Fougères R.
  • Gautier E.
  • Maire E.
  , 2001, pp.203-249.
• Inductive Logic Programming
  
  • Rouveirol Céline
  • Sebag Michèle
  , 2001, 2157. (10.1007/3-540-44797-0)
  DOI : 10.1007/3-540-44797-0
• Etude thermodynamique de l'évolution sous chargement dynamique de structures délaminées
  
  • Pradeilles-Duval Rachel Marie
  Comptes rendus de l’Académie des sciences. Série IIb, Mécanique, Elsevier, 2001, 329, pp.535-540. On considère un assemblage de plaques modélisant une structure stratifiée se délaminant. La propagation du délaminage est caractérisée par la transformation d'une plaque en deux autres. On examine dans le cadre du formalisme hamiltonien l'influence d'un chargement dynamique sur une telle structure, d'un point de vue thermodynamique. L'étude du taux de restitution associé à la propagation de la fissure, considérée comme une source de chaleur localisée sur le front de délaminage, est discutée. (10.1016/S1620-7742(01)01364-2)
  DOI : 10.1016/S1620-7742(01)01364-2
• X-ray computed tomography of sugar crystals flow in silo
  
  • Luong M. P.
  , 2001, pp.403-407. No abstract provided
• Exploiting complete or partial geometrical symmetry in Symmetric Galerkin BEM
  
  • Bonnet Marc
  , 2001, pp.527-534. No abstract provided
• Creep of argillites under small mechanical loading
  
  • Bérest Pierre
  • Charpentier Jean-Pierre
  • Valès Frédéric
  , 2001. Study of rocks under small (typically s = 0.1 MPa) mechanical loading is of great importance both for a better understanding of geological deformation features and for the analysis of rock mass behavior at large distance from underground openings. A very small amount of experimental data is available. Very long-term tests are required, as the creep rates induced by such small mechanical loading are exceedingly small (10 ­13 to 10-12s-1). Accurate displacement measurements and a thorough control of both hygrometry and temperature must be used. We used high resolution displacements sensors, whose resolution is 10-9m, designed for purpose by P.A.Blum from IPG Paris. The creep test system were set in a 20-m deep gallery where hygrometry is close to 100%PHs suburbs ; and in a 200-m deep salt mine where hygrometry is 54+/-2% RH . In both sites daily temperature fluctuations are smaller than a few hundredth of a Celsius degree, allowing for quite constant ambient conditions during several month long tests, the observed displacement-versus-time curves can be corrected from the thermoelastic effects. Creep of salt samples was measured in the 200-m deep mine ; transient creep, steady-state creep and the effcts of stress drop were observed during a 18-month long test. The measured steady-state creep rates (10-12s-1) are much faster than the values extrapolated from standard tests performed under larger mechanical loading. Argillite creep was measured in the 20-m deep gallery. High hygrometry conditions result in relatively fast clay swelling. In this context, argillite creep rate, which is slower than swelling rate by one order of magnitude, is difficult to identify
• Storage of tritiated water in salt caverns
  
  • Bérest Pierre
  • Brouard Benoit
  , 2001.
• A new approach for Hardening Rate Measurements in HCP Materials and Applications in Mechanical Modelling
  
  • Philippe Marie-Jeanne
  • Crépin Jérôme
  • Lecomte J.S.
  , 2001.
• Dynamique des systèmes de solides rigides avec liaisons unilatérales ou frottement
  
  • Ballard Patrick
  , 2001.
• Some aspects of dynamic testing with wave-guides
  
  • Gary G.
  , 2001.
• Intelligent design of woven composites
  
  • Zarka Joseph
  • Doux Thierry
  , 2001. (10.1016/S0167-6636(02)00259-4)
  DOI : 10.1016/S0167-6636(02)00259-4
• Étude modale d'une clarinette
  
  • Facchinetti Matteo Luca
  • Constantinescu Andrei
  • Boutillon Xavier
  , 2001. Ce travail est une contribution à la compréhension de la dynamique d’une clarinette en conditions de jeu. On propose une modélisation complète de l’instrument, en éléments finis fluides et solides, dont on analyse les modes propres réels : les résultats sont comparés avec des mesures expérimentales, par interférométrie holographique, en validant ainsi le modèle numérique.
• Boundary element based formulations for crack shape sensitivity analysis
  
  • Bonnet Marc
  Engineering Analysis with Boundary Elements, Elsevier, 2001, 25, pp.347-362. The present paper addresses several BIE-based or BIE-oriented formulations for sensitivity analysis of integral functionals with respect to the geometrical shape of a crack. Functionals defined in terms of integrals over the external boundary of a cracked body and involving the solution of a frequency-domain boundary-value elastodynamic problem are considered, but the ideas presented in this paper are applicable, with the appropriate modifications, to other kinds of linear field equations as well. Both direct differentiation and adjoint problem techniques are addressed, with recourse to either collocation or symmetric Galerkin BIE formulations. After a review of some basic concepts about shape sensitivity and material differentiation, the derivative integral equations for the elastodynamic crack problem are discussed in connection with both collocation and symmetric Galerkin BIE formulations. Building upon these results, the direct differentiation and the adjoint solution approaches are then developed. In particular, the adjoint solution approach is presented in three different forms compatible with boundary element method (BEM) analysis of crack problems, based on the discretized collocation BEM equations, the symmetric Galerkin BEM equations and the direct and adjoint stress intensity factors, respectively. The paper closes with a few comments. (10.1016/S0955-7997(01)00025-X)
  DOI : 10.1016/S0955-7997(01)00025-X
• On shakedown theorems in hardening plasticity
  
  • Nguyen Quoc Son
  • Pham Duc Chinh
  Comptes rendus de l’Académie des sciences. Série IIb, Mécanique, Elsevier, 2001, 329, pp.307-314. The model of generalized standard materials gives a convenient framework to extend Koiter's shakedown theorems into hardening plasticity. The extension of the static shakedown theorem (Melan–Koiter's theorem), proposed previously in [5], is considered here. It leads to the definition of safety coefficients in hardening plasticity by duality. Static and kinematic approaches are discussed for the models of isotropic hardening, of linear kinematic hardening (Ziegler–Prager's model) and of limited kinematic hardening. This discussion also leads to an extension of Koiter's kinematic shakedown theorem and to a second kinematic coefficient. (10.1016/S1620-7742(01)01321-6)
  DOI : 10.1016/S1620-7742(01)01321-6
• Experimental and numerical characterisation of in plane deformation in two-phase materials
  
  • Soppa Ewa Anna
  • Doumalin Pascal
  • Binkele Peter
  • Wiesendanger Tobias
  • Bornert Michel
  • Schmauder Siegfried
  Computational Materials Science, Elsevier, 2001, 21 (3), pp.261-275. The aim of the present work consists in the comparison of in-plane strain fields with out-of-plane displacements in micro-areas of an Ag/Ni-composite after a macroscopic compressive deformation of 8.6%. The in-plane deformations in an Ag/Ni-composite have been analysed experimentally with a high resolution object grating technique and numerically using the finite element method. The out-of-plane displacements were measured with an atomic force microscope (AFM). The development of local strain fields in micro-areas at the surface of an Ag/Ni-composite was simulated numerically using the FE-method in plane strain condition. A real cut-out of the microstructure served as input for the calculation. The out-of-plane displacements determined by AFM measurements were used further to correct the in-plane values of strains evaluated by the object grating technique. The roughness on the surface of the sample was characterised by fractal dimensions and compared with the in-plane strains in the same micro-region. (10.1016/S0927-0256(01)00170-7)
  DOI : 10.1016/S0927-0256(01)00170-7
• Modal analysis of a complete clarinet
  
  • Facchinetti Matteo Luca
  • Boutillon Xavier
  • Constantinescu Andrei
  , 2001. A modal computation of a complete clarinet is presented by the association of finite-element models of the reed and of part of the pipe, and a lumped-element model of the rest of the pipe. This is a continuation of an initial work by Pinard and Laine (unpublished reports of the Ecole Polytechnique) on isolated reeds. The eigenmodes of the complete system are computed and the results lead to a discussion of the following points: flexion and torsion modes of the reed, their coupling to the acoustical field, plane wave hypothesis, equivalent volume approximation in the mouthpiece, and alignment of resonance peaks.
• Increasing the maximum strain measured with the elastic and viscoelastic Hopkinson bars
  
  • Othman Ramzi
  • Bussac Marie-Noëlle
  • Collet Pierre
  • Gary Gérard
  , 2001.
• Tomographie aux rayons X de l'écoulement du sucre en poudre ensilé
  
  • Luong M. P.
  , 2001. No abstract provided
• Moving discontinuities: applications to fracture and wear
  
  • Stolz Claude
  , 2001.
• Caractérisation de l'écrouissage dans des monocristaux de Zirconium
  
  • Lecomte J. S.
  • Crépin Jérôme
  • Philippe Marie-Jeanne
  , 2001.
• Modification du critère de Gurson par une approche micromécanique
  
  • Bilger Nicolas
  • Auslender François
  • Bornert Michel
  • Masson Renaud
  • Zaoui André
  , 2001.
• Matériaux du nucléaire
  
  • Zaoui A.
  , 2001.
• Some recent advances in symmetric Galerkin boundary element methods and their coupling with finite elements
  
  • Bonnet Marc
  , 2001.
• Evolution de la pression dans une caverne remplie de fluide
  
  • Bérest P.
  • Brouard B.
  • Bergues J.
  • Durup G.
  , 2001, pp.96. No abstract provided
• Un exemple d'onde stick-slip
  
  • Moirot F.
  • Nguyen Q. S.
  , 2001, pp.229-236. No abstract provided