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Made available in DSpace on 2016-12-12T20:25:11Z (GMT). No. of bitstreams: 1 Thiago Andre Carniel.pdf: 5594070 bytes, checksum: 5e24f59f581ec79c2edb07d9afdd502e (MD5) Previous issue date: 2013-07-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents the development of a numerical formulation for the transient analysis of spatial truss structures considering geometrical and material nonlinearities. The equilibrium problem is formulated using the Principle of the Virtual Power in a current Lagrangian description. The displacement and velocity fields are discretized employing the Finite Element Method and the nonlinear equilibrium equations are solved by the full Newton- Raphson procedure. In order to obtain quadratic convergence, the algorithmic tangent matrix expression is developed and presented. Next, the transient problem is formulated and solved using the Newmark integration algorithm. The material model adopted is viscoelastic-viscoplastic coupled to Lemaitre s damage. The viscoelastic behavior is represented by the generalized Kelvin-Voigt rheological model and the viscoplastic contribution is introduced via Perzyna s equation. The evolution laws of the material model are integrated numerically using the implicit Euler scheme, resulting in the corresponding return mapping. The algorithmic tangent modulus for this material model is derived and validated by means of numerical differentiation using the complex variable approach. The constitutive parameters for the model are obtained by minimization of the difference between experimental and numerical curves, aiming at polymeric materials. Since non-uniqueness is expected for the minimization problem, the gradient free Particle Swarm Optimization method (PSO) is adopted for its solution. Finally, the results obtained and some particularities of the proposed model are discussed. / Este trabalho tem por objetivo desenvolver uma formulação numérica para a análise transiente de estruturas treliçadas tridimensionais considerando não linearidade geométrica e material. O problema de equilíbrio é apresentado através do Princípio das Potências Virtuais segundo uma formulação Lagrangeana Corrente. O campo de deslocamentos e velocidades é discretizado através do Método dos Elementos Finitos. As equações não lineares de equilíbrio são resolvidas pelo método de Newton-Raphson, sendo apresentado o desenvolvimento da matriz de rigidez tangente consistente. Posteriormente, o problema transiente é formulado, sendo as equações do movimento solucionadas pelo método de integração implícito de Newmark. O modelo constitutivo proposto é viscoelástico-viscoplástico acoplado com o modelo de dano de Lemaitre. A formulação viscoelástica é representada pelo modelo generalizado de Kelvin-Voigt e a contribuição viscoplástica é dada pela equação de Perzyna. As leis de evolução do modelo material são integradas numericamente através do algoritmo implícito de Euler, resultando no algoritmo de retorno. Para obter a taxa de convergência quadrática do método iterativo de Newton-Raphson durante o equilíbrio estrutural, é apresentado o cálculo analítico do módulo tangente algoritmo consistente, o qual é validado através do método da derivada complexa. Os parâmetros materiais são encontrados através do ajuste entre as curvas experimental e teórica, visando a aplicação para materiais poliméricos. Para o ajuste das curvas utilizou-se o método de Otimização por Nuvem de Partículas Particle Swarm Optimization (PSO). Ao final é realizada uma discussão dos resultados encontrados e comentado as particularidades do modelo proposto.

Dans les générateurs de vapeur des centrales nucléaires à eau pressurisée, les tuyauteries sont soumises à des chargements thermique et mécanique, qui sont variables et divisés en deux régimes différents : la fatigue oligocyclique et la fatigue gigacyclique. Les aciers au carbone – manganèse, type A42, A48 et Tu48 (normes françaises) sont souvent utilisés dans de telles applications. Les propriétés du matériau manifestent certains caractères spéciaux en mécanique et métallurgie comme le vieillissement dynamique conduisant à une augmentation de la valeur de la contrainte maximale et une diminution de la ductilité à la température 200 ℃. Le comportement en fatigue oligocyclique et gigacyclique sont étudiés à température ambiante et 200 ℃. Des essais de fatigue cumulée ont été mis en oeuvre pour étudier l’effet du cumul de dommage combinant des cycles de fatigue oligocyclique suivis de cycles en fatigue gigacyclique. Tous les résultats sont analysés en utilisant la mécanique de l’endommagement des milieux continus et l’analyse microfractographique. Les cycles d’hystérésis en fatigue oligocyclique sont dus à la déformation plastique de durcissement cinématique, ils peuvent être décrits par sous le modèle d’Armstrong – Frederick ; le durcissement isotrope est utile pour prédire l’évolution de l’amplitude de contrainte. Mais avec l’augmentation de la déformation plastique accumulée, le dommage ne peut être négligé. Le modèle de Chaboche d’endommagement par fatigue est utilisé pour décrire l’évolution des dommages oligocyclique et il est étendu au régime gigacyclique. Un modèle de fatigue cumulée des dommages a été développé à partir du modèle de Chaboche et appliqué à l’estimation des dommages de fatigue pour décrire le comportement de l’évolution de la contrainte en fonction du nombre de cycles. En fatigue oligocyclique à la température de 200 ℃, l’acier A48 est sensible au phénomène de vieillissement dynamique et il apparaît un durcissement secondaire, qui peut être prédit par la théorie des dislocations et est simulé dans la thése. L’analyse des surfaces de rupture est effectuée par fractographie au Microscope Electronique à Balayage pour les essais en oligocyclique, gigacyclique et cumul. En fatigue oligocylique, la fissure est initiée en surface. En fatigue gigacyclique, certaines fissures sont initiées sur des inclusions situées à l’intérieur d’éprouvettes. / In steam generators of nuclear power plants, typical pipes components are subjected to thermal and mechanical loading which are variable and divided into two different regimes: low cycle fatigue and gigacycle fatigue. Carbon-manganese steels A42, A48 and Tu48 steels (French standards) are often used in such applications. The material properties manifest some special characters in mechanics and metallurgy such as Dynamic Strain Aging, increasing UTS values in 200℃ temperature domain. The LCF and VHCF behaviors are investigated respectively by test method at room temperature and 200℃. The cumulative fatigue tests are implemented through referencing the load as prior LCF following gigacycle fatigue from the steam generator pipes thermal loads in order to obtain the performance of material under accumulated fatigue damage. All the test results are analyzed by using plastic mechanics, continuums damage mechanics and microscopic analysis. Hysteresis loops are due to plastic deformation in LCF which is the effect of kinematic hardening and they can be described by Armstrong – Frederick form models; the isotropy hardening is used to predict the evolution of stress amplitude in LCF. But with rising of accumulated plastic deformation, the damage can not be neglected. The Chaboche fatigue damage model is applied to describe the damage evolution of LCF and extended to VHCF regime. The cumulative fatigue damage model is extended from Chaboche model and applies to the estimation cumulative fatigue damage. The constitutive relationship and isotropy rule are coupled with fatigue damage model that can describe the whole fatigue behavior. In 200℃ for LCF, A48 is sensitive to dynamic strain aging and its secondary hardening behavior is important which can be predicted by dislocation theory and is simulated in the paper. The fractographic analysis is performed by SEM for LCF, VHCF and cumulative fatigue tests. The LCF crack is initiated in surface. Some of cracks of VHCF are given birth from the inclusions located at interior of sample.

Este trabalho apresenta um novo modelo numérico para simulação de juntas de argamassa em estruturas de alvenaria no plano via método dos elementos finitos. Neste modelo, blocos de alvenaria e juntas de argamassa são representados separadamente. Elementos finitos com alta razão de aspecto são utilizados para representar as juntas de argamassa e são inseridos na malha de elementos finitos através de uma técnica de fragmentação de malha. A principal vantagem desta técnica consiste na utilização de modelos constitutivos contínuos para representar regiões descontínuas, uma vez que seu campo de deformações quando a altura do elemento de interface tende a zero é semelhante ao apresentado pela abordagem de aproximação contínua de descontinuidades fortes. Um modelo constitutivo contínuo baseado na mecânica do dano foi desenvolvido para representar o comportamento dos elementos de interface. Este modelo consegue representar a abertura e fechamento de fraturas, bem como o efeito de atrito em função da tensão de confinamento nas interfaces. Como o objetivo deste trabalho consiste na simulação da formação e propagação de fraturas ao longo das juntas de argamassa, comportamento elástico linear foi atribuindo aos elementos triangulares de três nós utilizados na discretização dos blocos de alvenaria. Vários exemplos numéricos são apresentados. Inicialmente, testes básicos são realizados para demonstrar as principais características do modelo quando submetido a carregamentos de tração, compressão e cisalhamento. Posteriormente, estruturas de alvenaria submetidas a carregamentos estáticos são analisadas e os resultados comparados com as respostas experimentais a fim de validar o modelo proposto. A técnica proposta se mostrou bastante promissora para simulação da formação e propagação de fratura em juntas de argamassa de estruturas de alvenaria. / This work presents a novel numerical model to simulate the failure process in masonry structures subjected to static loads via finite element method. Brick and mortar joints are modeled separately with their own constitutive equations. Interface finite element with high aspect ratio are used to simulate the mortar interface and inserted by the mesh fragmentation technique. The main advantage of this strategy is supported by the fact that, as the aspect ratio of a standard low-order solid finite element increases, the element strains also increase, approaching the same kinematics as the Continuum Strong Discontinuity Approach. A constitutive model was developed, based on the continuum damage mechanics, in order to represent the behavior of the interface finite elements. This model is able to simulate the creation and propagation of cracks, as well as, the frictional effects in dependence on stress confinement on the interfaces. Furthermore, as the objective of this work aims to simulate the failure in the mortar joints, the brick elements are assumed as linear elastic material. Three node standard triangular finite element are used to represent the bricks. Several numerical models are carried out. Initially, basics tests are show in order to demonstrate the main characteristics of the proposed model subjected to tensile, compression and shear loads. Subsequently, masonry structures are subjected to static loads are analyzed and the results compared with the experimental responses in order to validate the proposed model. This technique proved to be very promising for the simulation of failure onset and propagation in mortar joints of masonry structures.

No presente trabalho desenvolve-se um modelo constitutivo baseado na mecânica do dano contínuo para representar o acúmulo da degradação do concreto produzido por cargas repetidas. O modelo de dano apresenta as condições necessárias exigidas na chamada aproximação de descontinuidades fortes proposta por Simó, Oliver e Armero e, conseqüentemente, pode ser empregado na formulação de elementos finitos com descontinuidade forte incorporada. Em decorrência de sua capacidade de descrever o comportamento do meio descontínuo independentemente da posição dos contornos do elemento finito, essa classe de formulação constitui uma alternativa valiosa para remediar a forte dependência da malha observada nos modelos de fissuras distribuídas, assim como para evitar as sofisticadas técnicas de reconstrução da malha exigidas nos modelos de fissura discreta, nos quais a fissura é introduzida na interface entre elementos. O trabalho traz contribuições no sentido de proporcionar uma ferramenta alternativa para a análise de propagação de fissuras por fadiga em elementos estruturais de concreto, dentro do contexto da mecânica do dano contínuo. Verifica-se a eficiência da formulação mediante análise numérica de problemas de fadiga em elementos estruturais de concreto. / A constitutive model based on the continuum damage mechanics is proposed to describe the accumulation of the degradation produced by repeated loads in concrete materials. The proposed damage model presents the necessary conditions required in the strong discontinuity approach advocated by Simó, Oliver and Armero and, consequently, it can be used in the embedded strong discontinuity finite element approach. This class of approach has been recognized by its capability to model discontinuities independently on the element boundaries. In fracture mechanics, the embedded strong discontinuity element has been proved to be a efficient alternative to remedy the strong mesh dependence verified in smeared crack approaches, as well as to avoid the sophisticated remeshing techniques required in the discrete crack approaches, in which the crack is introduced in the element interfaces. This work provides an alternative tool for the analysis of crack propagation in concrete structures under fatigue in the context of the continuum damage mechanics. Numerical analysis of concrete elements under fatigue are performed to access the effectiveness of the proposed approach.

Este trabalho busca avaliar a ductilidade de ligas metálicas utilizando como ferramenta a teoria da mecânica do dano proposta por Kachanov e desenvolvida por Lemaitre, a qual é apresentada desde as hipóteses básicas até as equações que modelam a deterioração de um material em regime de fratura dúctil. Como o enfoque do trabalho é a predição de trincas em processos de conformação mecânica, em especial estampagem de chapas, o mecanismo de formação destes defeitos é revisado, buscando na literatura o entendimento de como os parâmetros microestruturais influenciam na fratura dúctil. Ensaios de tração foram efetuados em corpos de prova retirados de chapas de aço SAE 1050 em duas condições microestruturais, cementita esferoidizada em matriz ferrítica e ferritaperlita, e em duas direções em relação à laminação da chapa original, paralelo e transversal. A evolução do dano foi medida de maneira indireta por meio da variação do módulo elástico e as propriedades mecânicas necessárias para utilização do modelo de Lemaitre foram calculadas. Por meio de difração de raios X, efetuamos o estudo da evolução da textura cristalográfica, apresentado na forma de figuras de distribuição de orientação e análise da intensidade das principais fibras encontradas em aços laminados a quente. Não foi observada influência significativa do tipo de microestrutura e da direção de deformação na evolução da textura. Por fim, o modelo de evolução de dano de Lemaitre foi transformado em um algoritmo numérico e implementado no código comercial Abaqus, em sua versão explícita, por meio do uso da subrotina VUMAT. Resultados foram obtidos e comparados com os experimentos, validando a aplicação do modelo. A evolução do dano para o aço SAE 1050 também foi comparada com resultados para outros aços ao manganês encontrados na literatura. Relações empíricas entre o teor de carbono e parâmetros como a deformação limite para início do dano, resistência à evolução do dano e dano máximo suportado foram desenvolvidas e apresentadas, com o intuito de funcionar como guias gerais para cálculo sem a necessidade de uma bateria de ensaios dedicados, facilitando a utilização da teoria da mecânica do dano em condições industriais. / The aim of the present work is to evaluate the ductility of metallic alloys employing the theory of damage mechanics as suggested by Kachanov and developed by Lemaitre, which is presented since its basic hypothesis until the equation that model the material deterioration under a regime of ductile fracture. As the focus of the work is the fracture prediction during mechanical working processes (mainly sheet metal stamping), the mechanism of formation of these defects is revised, based upon literature data, aiming at the understanding of how the material microstructural parameters influence ductile fracture. Tensile tests have been performed on samples obtained from SAE 1050 steel sheets for two microstructural conditions namely spheroidized cementite and regular ferrite-perlite for two rolling directions (rolling and transverse directions). In those tests, damage evolution has been measured indirectly through the materials variation in the Young modulus with strain, obtaining the mechanical properties, needed to be used in the calculation of Lemaitres model. Through X-ray diffraction measurements, the crystallographic texture evolution, presented in the form of orientation distribution functions and the associated fiber intensities observed for both microstructural conditions, has been evaluated. No major influence has been observed in this texture evolution, for the tested conditions. Finally, the Lemaitre damage evolution model has been transformed into a numerical algorithm and implemented in the Abaqus commercial code, in its explicit form, through the VUMAT sub-routine. Results have been obtained and compared with the experimental values, validating the suggested model. Damage evolution for the SAE 1050 steel has been also compared with results from literature for other C-Mn steels. Empirical relationships between C level and damage parameters such as limit strain for damage initiation, resistance to damage evolution and maximum allowable damage, have been developed and presented, envisaging their application as general guidelines, without requiring a sequence of dedicated tests, making easier the usage of damage mechanics under industrial conditions.

Textile Verstärkungsstrukturen werden aufgrund der hohen Variabilität der Fadenablage, dem erreichbaren hohen Automatisierungsgrad und der guten mechanischen Kennwerte in hochbeanspruchten Faser-Kunststoff-Verbundstrukturen eingesetzt. Eine besondere Rolle spielen hier 3D-Textilverstärkungen mit gestreckter Fadenanordnung etwa in Form von 3D-Geweben, Mehrlagengestricken und -gewirken. Sie bieten neben hervorragenden Steifigkeiten und Festigkeiten durch den in Dickenrichtung angeordneten und den Fadenverbund sichernden Maschenfaden einen hohen Widerstand gegen Delaminationen sowie eine gute Drapierbarkeit. In der Arbeit wird ein neuartiges Degradationsmodell für textilverstärkte Kunststoffe bei zyklischer Belastung auf Basis kontinuums-schädigungsmechanischer Ansätze entwickelt. Dazu wird zunächst die Schädigungsphänomenologie exemplarisch für Glasfaser-Mehrlagengestrickverstärktes Epoxidharz sowohl bei einachsiger als auch erstmals bei frequenz- und phasengleicher mehrachsiger zyklischer Belastung untersucht und klassifiziert. In umfangreichen Versuchsreihen sind belastungsspezifische Schäden - in den bereits für quasistatische Beanspruchung identifizierten Bruchmoden - zu beobachten, die sich in charakteristischer Weise über den Verlauf der zyklischen Belastung aufsummieren und eine deutliche Abhängigkeit von der Belastungsart und -richtung aufweisen. In den mehrachsigen Belastungsversuchen konnte die bislang unbekannte unterschiedliche Kopplung der Zug- und Schubsteifigkeitsverläufe bzw. Druck- und Schubsteifigkeitsverläufe quantifiziert und mit den auftretenden Schädigungsphänomenen korreliert werden. Die zur Kalibrierung des Materialmodells notwendigen Kennwerte und Modellparameter werden anhand von ein- und mehrachsigen Einstufenversuchen durch Auswertung der Spannungs-Dehnungs-Hysterese sowie der Schwingfestigkeitsschaubilder ermittelt. Das Potential der hier vorgenommenen schichtweisen Lebensdauermodellierung unter Berücksichtigung von Schädigungsinitiierung und Schädigungsevolution wird in ausgewählten Validierungsversuchen demonstriert. Neben der realistischen Abbildung des Degradationsverhaltens ist eine sehr gute Vorausberechnung der richtungsabhängigen Restfestigkeit nach zyklischer Belastung möglich. Das hier entwickelte Degradationsmodell liefert damit erstmals die wesentlichen schichtbezogenen Informationen zum Werkstoffzustand während zyklischer Belastung und ist ein essentieller Grundbaustein für die umfassende Lebensdaueranalyse von textilverstärkten Strukturbauteilen. / Due to the high variability of the thread placement, the achievable high degree of automation and the good mechanical properties textile reinforcements are used in highly loaded fiber reinforced polymer structures. A specific role is played here by 3D textile reinforcements with stretched thread arrangements, for example in the form of 3D fabrics and multi-layered weft knits. In addition to excellent stiffness and strength, they provide a high resistance to delamination as well as good drapability due to the mesh thread arranged in the thickness direction securing the thread system. In this work a novel degradation model for cyclically loaded textile-reinforced polymers on the basis of continuum damage mechanics approaches is developed. For this purpose, the damage phenomenology is investigated and classified for glass fiber multi-layer weft knit reinforced epoxy resin in uniaxial as well as in-phase multiaxial cyclic loading. In extensive tests load-specific damage can be observed - in the fracture modes already identified for quasistatic stress - which characteristically develop over the course of the cyclic load and show a clear dependence on the type and direction of loading. In the multi-axial load tests, the hitherto unknown coupling of the tensile and shear stiffness or compression and shear stiffness could be quantified and correlated with the occurring damage phenomena. The characteristic values and model parameters necessary for calibrating the material model are determined by means of single- and multi-axial constant amplitude tests by evaluating the stress-strain hysteresis and the S-N curves. The potential of the presented layer-wise fatigue damage model is demonstrated in selected validation experiments. In addition to the realistic modelling of the degradation behaviour, a very good prediction of the direction-dependent residual strength after cyclic loading is achieved. For the first time, the degradation model developed here provides the essential layer-related information on the state of the material during cyclic loading and is an essential building block for the comprehensive lifetime analysis of textile-reinforced composite structures.

Dans cette thèse, une nouvelle loi d'endommagement en traction des roches sous chargement exploisif est établie. Basée sur l'approche micro-mécanique et énergétique, la loi d'évolution d'endommagement dynamique est conçue à l'aide de la méthode mathématique d'homogénéisation basée sur le développement asymptotique, et en tenant compte de l'effet inertiel lors de la propagation de fissure. Les simulations numériques sont présentées en vue d'illustrer la capacité du modèle à décrire les comportements connus comme les effets de taille pour la réponse structurelle, la sensibilité au taux de déformation, la transition fragile-ductile et la dispersion de l'onde.<p><p>La loi est implémentée dans le code aux éléments finis LAGAMINE pour étudier la réponse macroscopique du modèle. Plusieurs cas d'applications en dynamique ont été examinés.\\<p><p>- En 1D, les problèmes de localisation ont été étudiés dans une barre sollicitée en traction dynamique par une rampe de chargement. Selon l'amplitude de chargement, trois réponses ont été identifiées: a) comportement purement élastique pour des faibles charges, b) localisation à l'extrémité encastrée de la barre pour des chargements modérés et c) localisation à la tête de la barre pour des chargements élevés. L'influence de la taille microstrurelle sur la localisation a été examinée. Des simulations numériques de l'essai de traction dynamique par écaillage ont été éffectuées. Des essais expérimentaux de traction dynamique par écaillage ont été réalisés sur la bauxite et ont permis de valider le modèle en comparant l'analyse post mortem de l'éprouvette aux résultats des simulations numériques d'écaillage. Ces essais ont aussi permis de déterminer les caractéristiques mécaniques du matériau, la résistance mécanique en traction dynamique, l'instant de rupture et la vitesse de déformation à rupture.\\<p><p>- En 2D, des simulations numériques sont efféctuées pour reproduire le comportement d'une mine sous charge explosive. Le modèle a été capable de reproduire l'endommagement en traction sous charge explosive. L'influence des paramètres du modèle tels que: l'orientation de fissures, la taille de microstructure et la valeur initial d'endommagement sur la distribution de l'endommagement autour du trou de charge a été étudiée. Enfin, un cas d'application sur les mines de bauxite de Guinée a été étudié, incluant un calcul de l'extension de la zone endommagée ainsi qu'une prédiction numérique du niveau de vibration engendrée suite aux tirs à l'explosif. La prédiction du modèle est globalement en accord avec les résultats de la littérature. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

L'objectif de ce travail est de proposer un modèle de comportement avec endommagement ductile pour la simulation des procédés de mise en forme de tôles minces qui peut bien représenter le comportement des matériaux sous des trajets de chargement complexes en grandes déformations plastiques. Basé sur la thermodynamique des processus irréversibles, les équations de comportement couplé à l’endommagement tiennent compte des anisotropies initiales et induites, de l’écrouissage isotrope et cinématique et de l’endommagement isotrope ductile. Les effets de fermeture des microfissures, de triaxialité des contraintes et de l’angle de Lode sont introduits pour influencer l’évolution de l’endommagement sous une large gamme de triaxialité des contraintes. La distorsion de la surface de charge est introduite via un tenseur déviateur qui gouverne la distorsion de la surface de charge. A des fins de comparaison, les courbes limites de formage sont tracées basées sur l’approche M-K.Des essais sont conduits sur trois matériaux pour les besoins d’identification et de validation des modèles proposés. L’identification utilise un couplage entre le code ABAQUS et un programme MATLAB via un script en langage Python. Après l’implémentation numérique du modèle dans ABAQUS/Explicite et une étude paramétrique systématique, plusieurs procédés de mise en forme de structures minces sont simulés. Des comparaisons expériences-calculs montrent les performances prédictives de la modélisation proposée / The objective of this work is to propose a “highly” predictive material model for sheet metal forming simulation which can well represent the sheet material behavior under complex loading paths and large plastic strains. Based on the thermodynamics of irreversible processes framework, the advanced fully coupled constitutive equations are proposed taking into account the initial and induced anisotropies, isotropic and kinematic hardening as well as the isotropic ductile damage. The microcracks closure, the stress triaxiality and the Lode angle effects are introduced to influence the damage rate under a wide range of triaxiality ratios. The distortion of the yield surface is described by replacing the usual stress deviator tensor by a ‘distorted stress’ deviator tensor, which governs the distortion of the yield surfaces. For comparisons, the FLD and FLSD models based on M-K approach are developed.A series of experiments for three materials are conducted for the identification and validation of the proposed models. For the parameters identification of the fully coupled CDM model, an inverse methodology combining MATLAB-based minimization software with ABAQUS FE code through the Python script is used. After the implementation of the model in ABAQUS/Explicit and a systematic parametric study, various sheet metal forming processes have been numerically simulated. At last, through the comparisons between experimental and numerical results including the ductile damage initiation and propagation, the high capability of the fully coupled CDM model is proved

L’objectif de ce travail est de développer une modélisation prédictive du comportement et de la rupture ductile des matériaux métalliques à anisotropies initiales et induites par l’endommagement. La thermodynamique des processus irréversibles est utilisée comme cadre pour la formulation proposée. Le modèle de comportement est élastoplastique anisotrope avec écrouissage non linéaire isotrope et cinématique en grandes déformations plastiques, avec une théorie non associée à normalité associée, basée sur des normes de contraintes quadratiques. L’endommagement ductile anisotrope est décrit par un tenseur du second ordre symétrique dont l’évolution est décrites par des relations de type Lemaitre-Desmorat. Le couplage fort comportement-endommagement est réalisé dans le cadre de l’hypothèse de l’équivalence en énergie totale où l’effet de l’endommagement sur le comportement est introduit par un tenseur « effet d’endommagement » d’ordre quatre symétrique de type Murakami. Après une caractérisation expérimentale des mécanismes physiques de l’endommagement dans l’acier AISI 316L, le modèle de comportement avec endommagement a été identifié. Une fois discrétisé et implémenté dans le code de calcul de structures ABAQUS/Explicit®, une étude paramétrique et de nombreuses simulations numériques de l’endommagement anisotrope en mise en forme de quelques structures ont été réalisées et discutées en détail / The objective of this work is to develop a predictive modeling of behavior and ductile fracture of metallic materials with initial anisotropy and induced by the ductile anisotropic damage. Thermodynamics of irreversible processes is used as a framework for the proposed formulation. The model is anisotropic elastoplastic with non-linear isotropic and kinematic hardening under large plastic strains. It is formulated in the framework of the non-associative plasticity theory with associative normality rule and based on quadratic equivalent stress. The anisotropic ductile damage is described by a symmetric second-rank tensor whose evolution is described by Lemaitre /Desmorat type relationships. The strong damage-behavior coupling is done under the assumption of total energy equivalence where the effect of the anisotropic damage is introduced by a fourth-rank symmetric damage-effect tensor of Murakami kind.After an experimental characterization of the main physical mechanisms of anisotropic damage in stainless steel AISI 316L, the behavior model with damage has been identified. Once discretized and implemented in the computer code ABAQUS / Explicit ®, a parametric study and many numerical simulations of anisotropic damage in some metal forming processes have been carried out and discussed in detail