Publications

2000

• A Concept for Earthquake-Resistant Design of Underground Structures: Stress Response Spectrum
  
  • Kurose Ayumi
  • Bérest Pierre
  , 2000, pp.1043-1049. This paper introduces a method to evaluate the mechanical effects induced in the cross-section of an underground structure, constructed in a medium of great thickness, under earthquake ground motion. Damage observations after large earthquakes (e.g., Kobe, 1995) have shown the cross-sectional vulnerability of underground structures at shallow or great depth. Present earthquake-resistant design standards only suggest calculation methods for structures constructed in a soil laying over a rigid basement and cannot be applied to a structure constructed in a medium of great thickness, such as a tunnel, an underground hydrocarbon storage facility or a nuclear-waste disposal site. Thus, development of a systematic method to evaluate the seismic effects induced in the cross-section of a structure in an unbounded medium is of interest. The approach proposed here is conceptually similar to that used for earthquake response analysis of buildings: using a simple but realistic model of an underground linear structure (a 2D cavity with circular cross-section in an infinite, elastic, linear, homogeneous and isotropic medium) and real earthquake records, we propose a response spectrum more suitable, than the usual velocity or acceleration response spectrum, for analyzing the structural stability of underground construction during earthquakes: the Stress Response Spectrum (SRS), which is defined as the maximum value of the maximum shear stress at the cavity wall during the duration of ground motion. The SRS values are computed by using 21 earthquake motions (provided by the Japan Meteorological Agency) of magnitude higher than 4, which were recorded by the Japan Nuclear Cycle Research Institute (JNC) in a 315-meter deep gallery excavated in an a granodioritic rock mass at the Kamaishi Mine in Iwate, Japan. In light of the numerical analysis, the SRS appears to be a potential tool for the earthquake-response analysis of underground structures. The Stress Response Spectrum will provide engineers with the order of magnitude of mechanical effects in an underground structure for a given earthquake motion; conversely, for a given target SRS, may assist in producing a design earthquake more suitable for analysis of deep underground structures than those currently available.
• Computational and experimental investigations of the local strain field in elastoplastic two-phase materials
  
  • Doumalin Pascal
  • Bornert Michel
  • Soppa Ewa
  , 2000, pp.323-328.
• Surface deformation analysis of composites by mesomechanics
  
  • Soppa E.
  • Doumalin Pascal
  • Bornert Michel
  • Schmauder S.
  , 2000, 3, pp.443-449. No abstract provided
• Micromechanical applications of digital image correlation techniques
  
  • Doumalin P.
  • Bornert Michel
  , 2000, pp.67-74. No abstract provided
• Dissipation intrinsèque d'un matériau sableux
  
  • Luong M. P.
  , 2000, pp.127-132. No abstract provided
• Simulation expérimentale du risque en génie civil
  
  • Luong M. P.
  , 2000, pp.77-106. No abstract provided
• Influence of the film thickness on texture, residual stresses and cracking behaviour of PVD tungsten coatings deposited on a ductile substrate
  
  • Ganne T.
  • Farges G.
  • Crépin Jérôme
  • Pradeilles-Duval R. M.
  • Zaoui A.
  , 2000. No abstract provided
• Effet de la fréquence de sollicitation et de l'environnement sur la propagation des fissures de fatigue en mode II dans l'acier maraging M250
  
  • Doquet V.
  , 2000. No abstract provided
• Adaptive mesh for inelastic analysis of structures
  
  • Zarka J.
  • Hablot J. M.
  , 2000. No abstract provided
• Modelisation d un contact plan/plan entre un graphite et du Ti6Al4V renforce TiC : essai de tribocorrosion anneau/disque, analyse de l usure des materiaux
  
  • Serre I.
  • Celati N.
  • Pradeilles Duval R. M.
  , 2000. No abstract provided
• Application of modal analysis and synthesis of reed and pipe to numerical simulations of a clarinet
  
  • Facchinetti Matteo
  • Boutillon Xavier
  • Constantinescu Andrei
  , 2000, 108 (5), pp.2590-2590. A finite-element model of a complete clarinet is proposed in order to simulate the acoustical dynamics of the instrument. Following the work of Pinard and Laine on isolated reeds [unpublished reports of the Ecole Polytechnique], modal analysis of clarinet reeds performed with holographic interferometry has been compared with modal synthesis derived from the FEM. In this linear model, the reed is considered alone first, then coupled to the mouthpiece, and finally to the mouthpiece and the barrel. The good agreement between the two approaches makes the mixed solid-acoustical FEM usable in a numerical simulation of the whole clarinet. The rest of the pipe is modeled by lumped mechanical elements whose parameters are fitted with measurements of the acoustical input impedance. Eigenmodes of the complete system—reed, mouthpiece, barrel, pipe—are computed and damping is subsequently attributed to each mode. The evolution of the system subject to nonlinear boundary conditions—incoming airflow, one-sided contact of the reed against the curved lay of the mouthpiece—is computed in the time domain: at each time step, external forces and internal variables are projected onto the modal basis and the evolution of each modal amplitude is integrated. Findings of the simulations will be discussed. <p style="color:red">[NO PDF]</p> (10.1121/1.4743630)
  DOI : 10.1121/1.4743630
• Plastic heterogeneities of a copper multicrystal deformed in uniaxial tension: experimental study and finite element simulations
  
  • Delaire F.
  • Raphanel Jean L
  • Rey Colette
  Acta Materialia, Elsevier, 2000, 48, pp.1075-1087. A copper sample made of a single layer of grains is plastically deformed by uniaxial tension at room temperature and low strain rate. The deformation field is measured by means of grids deposited on the polished surface of the undeformed specimen and local orientations are recorded using electron back scattering diagrams in a scanning electron microscope. These measures are compared with simulations made by a finite element code using a physically based model for the deformation and hardening of face centered cubic crystals. A good agreement is found between measured and computed values. The simulations give access to much more detail about the history of glide in each grain and help establish which systems are active at a local level. They also provide the evolution of internal variables such as dislocation densities. A new insight into intergranular accommodation as well as intragranular heterogeneities is provided. (10.1016/S1359-6454(99)00408-5)
  DOI : 10.1016/S1359-6454(99)00408-5
• Thermodynamical description of moving discontinuities : application to fracture and wear
  
  • Stolz C.
  , 2000, pp.1463-1468. No abstract provided
• Micromechanics-based modeling of plastic polycrystals: an affine formulation
  
  • Zaoui André
  • Masson Renaud
  Materials Science and Engineering: A, Elsevier, 2000, 285, pp.418-424. Recent comparisons of predictions associated with Hill’s original ‘incremental’ formulation for the self-consistent modelling of elastoplastic polycrystals with a newly available nonlinear upper bound for the moduli have brought to light the fact that this formulation leads to a frequent violation of this bound. This conclusion has motivated the conception of a new formulation, called the ‘affine formulation’, which is expected to yield softer predictions. The principle of this formulation is first reported for the simpler case of nonlinear elasticity (or viscosity) and compared with other approaches. It is then extended to cases for which the current responses depend on the loading path, with specification to the self-consistent scheme in order to model transient responses of polycrystals; though no variational approach exists in these cases, the obtained predictions can be considered as improved ones since they are shown to be, as expected, softer than those derived from other models. (10.1016/S0921-5093(00)00687-0)
  DOI : 10.1016/S0921-5093(00)00687-0
• Une approche non destructive pour l'identification de contraintes de contact
  
  • Ben Abdallah J.
  • Bonnet Marc
  Comptes Rendus de l'Academie des Sciences Serie II, Gauthier-Villars, 2000, 328, pp.525-529. Cette note concerne une méthode non destructive d'identification de la distribution de contraintes de contact entre un poinçon rigide et un massif élastique semi-infini au moyen de mesures du déplacement normal et des déformations tangentielles à la surface libre du massif. Les résultats numériques, obtenus pour des configurations axisymétriques, valident cette méthode, y compris en présence de données expérimentales inexactes et quand la zone de contact n'est pas a priori exactement connue (expérience d'indentation). (10.1016/S1620-7742(00)00022-2)
  DOI : 10.1016/S1620-7742(00)00022-2
• Deformation mechanisms and strain localization at the brittle-ductile transition of the continental crust in extension
  
  • Gueydan Frédéric
  • Leroy Yves
  • Jolivet Laurent
  , 2000.
• Treatment of singular integrals in 3D symmetric Galerkin boundary element method
  
  • Mouhoubi Saida
  • Ulmet L.
  • Bonnet Marc
  , 2000. No abstract provided
• On the indentification of planar cracks in 3D acoustics
  
  • Bui Huy Duong
  • Constantinescu Andrei
  • Maigre Hubert
  , 2000, pp.181-190.
• Modèles micromécaniques : effets de l'anisotropie et de l'hétérogénéité de la répartition des renforts dans un composite à particules
  
  • Bornert Michel
  • Lebail H.
  • Franciosi P.
  • Jeulin Dominique
  , 2000. No abstract provided
• Etude pétro-structurale du détachement du Tende (Corse). Rôle des micas blancs dans la localisation de la déformation ductile
  
  • Gueydan F.
  • Jolivet L.
  • Agard Philippe
  , 2000. No abstract provided
• Evaluation non destructive des structures mécaniques par thermographie infrarouge
  
  • Luong Minh-Phong
  Rev. Franç. Mécanique, 2000, 2000, pp.19-25.
• On viscous fluid flow near the moving crack tip
  
  • Bui Huy Duong
  • Guyon Corinne
  • Thomas Bernadette
  , 2000, 76, pp.63-74. We consider a crack partially filled with a fluid. We show that the presence of a lag avoids the appearance of pressure and velocity singularities. For the static equilibrium, we recall the previous result on the Capillary Stress Intensity Factor which provides a purely mechanical explanation of the Rehbinder effect, according to which the toughness of the material can be lowered by humidity. For the steady state propagation of a crack due to viscous fluid flow, we set the coupled system of non-linear equations. (10.1007/0-306-46946-4_4)
  DOI : 10.1007/0-306-46946-4_4
• Infrared thermography of the tensile behavior of natural gut string
  
  • Luong M. P.
  , 2000, pp.423-430. No abstract provided
• Modelisation of dynamic crack propagation criteria
  
  • Karimzada T.
  • Maigre H.
  Journal de Physique IV Proceedings, EDP Sciences, 2000, 10, pp.461-466. The aim of this study is the analysis of the dynamic crack propagation criteria in materials under impact loading. We want to define which mechanical quantities monitor the propagation, then use these parameters in numerical simulations and finally compare the results with dynamic propagation experiments. First, we propose a 1D semi-analytical model. In this model several mechanical quantities can be used to define the propagation criterion, like the energy release rate... The effect of the applied loading and the reflections of waves is also very important, leading sometimes to a stick-slip propagation. Next, we present a 2D modelisation. In this case, it is not possible to study analytically the effect each criterion and we need to use a numerical simulation. We propose a numerical method based on finite element. The propagation is simulated by releasing nodes with a the release criterion defined from the propagation criterion. The numerical scheme is chosen to respect the equivalence between the total dissipation and the fracture dissipation. In parallel, we have performed dynamic propagation experiments on PMMA. The samples are DCB specimens loading with a wedge in a Kolsky set-up. During each test, the location of the crack has been recorded 4 times with high speed cameras (1 microsecond shutter). (10.1051/jp4:2000977)
  DOI : 10.1051/jp4:2000977
• Spatial localization of the error of constitutive law for the identification of defects in elastic bodies
  
  • Bui Huy Duong
  • Constantinescu Andreï
  Archives of Mechanics, Polish Scientific Publishers Pwn, 2000, 52, pp.511-522. The error on constitutive law (ECL) is a cost functional currently used in inverse problems for identifying interior distribution of coefficients of partial differential equations from overspecified boundary conditions. In previous works, different authors have shown that the ECL permits a good spatial localization of the perturbations of the coefficients. The purpose of this paper is to justify this spatial localization property. The result is obtained for the elliptic equations of elasticity using boundary integral representations of the solutions and comparing the linear and the perturbed solution of the problem.