2,233 research outputs found
Validation of low velocity impact modelling on different stacking sequences of CFRP laminates and influence of fibre failure
No full textThis paper presents a validation of low-velocity impact Finite Element (FE) modelling. Based on switching ply location of reference layup [02,452,902,-452]s T700GC/M21 laminated plates from Bouvet et al. (2012) [1], twelve possible layups under a constraint of double-ply, mirror-symmetric, balanced, and quasi- isotropic are allowed. However only seven layups are chosen for the study and one of them reveals the importance of longitudinal fibre compressive failure during impact events. Therefore, the second aspect of this work is the introduction of a fibre compressive failure law associated with fracture damage development. This makes it possible to improve the simulation for all seven different layups. Good correspondence is achieved between simulation and experiment for aspects such as delamination areas/shapes and force–displacement responses. The influence of the addition of fibre compressive failure according to fracture toughness in mode I is discussed
« En face / d’événements / en face / des gens / et toujours la télévision / entre nous ». Le 11 septembre 2001 vu par deux poètes contemporains (Patrick Bouvet, Christophe Fiat)
No full textDirect, de Patrick Bouvet, et New York 2001 de Christophe Fiat, deux livres de poésie consacrés au 11 septembre 2001, ont pour point commun de s’intéresser au traitement médiatique de l’événement. A travers un geste de reprise et de remise en branle des discours qui ont accompagné l’événement, ces deux poètes interrogent et critiquent le processus de fictionnalisation, d’éloignement du réel de l’événement dans le spectacle. Mais derrière la critique se profile également une tentative pour ressaisir l’événement dans sa singularité, en tant qu’il peut advenir dans et par la langue.Direct by Patrick Bouvet and New York 2001 by Christophe Fiat are two collections of poems devoted to September 11th 2001. They share a common interest in how the media deal with the event. By considering and replaying the words that were uttered at the time of the event both poets question and criticize how the event has been fictionalized and turned into a show. But against the criticism they try as well to grasp the singularity of the event , how it occurs through and by language.Direct, de Patrick Bouvet, et New York 2001 de Christophe Fiat, dos libros de poesía dedicados al 11 de septiembre de 2001, comparten un mismo interés por el tratamiento mediático del evento. Mediante un acto de recuperación y de reactivación del discurso que acompañó el evento, ambos poetas cuestionan y critican el proceso de ficcionalización, de distanciamiento de lo real del evento en el espectáculo. No obstante, detrás de las críticas se perfila un intento de captar el evento en toda su singularidad, en tanto que puede suceder en y a través del lenguaje
Le multiculturalisme au coeur
No full textWalzer Michael, Kastoryano Riva, Bouvet Laurent, Jaffrelot. Le multiculturalisme au coeur. In: Critique internationale, vol. 3. 1999. Crime et politique en démocratie, sous la direction de Didier Bigo. pp. 55-63
Discrete ply model of circular pull-through test of fasteners in laminates
No full textIn aeronautical structures, assemblies with thin laminates are becoming increasingly usual, especially for fuselage design. In these structures, out-of-plane loads can appear in bolted joints and can lead to progressive punching of the fastener’s head in the laminate resulting, in some cases, in a failure mode called pull-through [1]. This complex phenomenon, which occurs in assemblies, was studied firstly by using a simplified ‘‘circular’’ pull-through test method. Qualitative micrographic examinations showed damage very similar to that observed in impacted specimens. The research presented here extends the Discrete Ply Model Method (DPM) developed by Bouvet et al. [2] to this case. The finite elements model is based on a particular mesh taking ply orientations into account. Cohesive elements are placed at the interfaces between solid elements to represent matrix cracks and delamination, thus allowing the natural coupling between these two damage modes to be represented. The model shows good correlation with test results, in terms of load/displacement curve, and correct prediction of the damage map until failure, including the
splitting phenomenon
Tradução de uma disputa : Christophe versus Pétion em La tragédie du roi Christophe, de Aimé Césaire
No full textEsta contribuição propõe a tradução comentada da primeira cena da peça de teatro La Tragédie du roi Christophe (A tragédia do rei Christophe), de Aimé Césaire. O texto foi publicado pelo autor martinicano em 1963 e encenado a partir de 1964. A história aborda o embate histórico entre os dois líderes revolucionários haitianos, Alexandre Pétion (1770-1818) e Henry Christophe (1767-1820), após o estabelecimento da independência do Haiti, em 1804. O ex-escravizado Henry Christophe I, autoproclamado rei do Haiti em 1811, protagoniza, na peça, os impasses políticos decorrentes do processo de descolonização para a constituição de um novo estado haitiano livre e democrático. Optamos por traduzir a cena que anuncia e ilustra, na abertura do primeiro Ato, o caráter trágico que permeia o desenrolar dos eventos.This contribution proposes the commented translation of the first scene of the play La Tragédie du roi Christophe (The tragedy of King Christophe), by Aimé Césaire. The text was published by the Martinican author in 1963 and staged from 1964 onwards. The story addresses the historical clash between the two Haitian revolutionary leaders, Alexandre Pétion (1770-1818) and Henry Christophe (1767-1820), after the establishment of Haitian independence in 1804. The ex-enslaved Henry Christophe I, self-proclaimed King of Haiti in 1811, stars, in the play, political impasses resulting from the decolonization process, for the constitution of a new free and democratic Haitian state. We chose to translate the scene that announces and illustrates, in the opening of the first Act, the tragic character that permeates the unfolding of events
Modelling of impact damage and permanent indentation on laminate composite plate
No full textThis paper deals with impact damage and permanent indentation modelling. A model enabling the formation of damages developing during a low velocity / low energy impact test on laminate composite panels has been elaborated. The different impact damages developing during an impact test, i.e. matrix cracking, fibres failure and interfaces delamination, are simulated. The interlaminar damages, i.e. interfaces delamination, are classically simulated thanks to interface finite elements based on the fracture mechanics. The particularity of this model is to account for the intralaminar damages, i.e. matrix cracks, thanks to interface finite elements which respect their discontinue character. These interface elements allow equally to simulate the permanent indentation during the impact unloading. This impact mark modelling is very original in the literature, and should allow to entirely design a composite structure thanks to impact damage tolerance
Low velocity impact modeling in composite laminates capturing permanent indentation
No full textThis paper deals with impact damage and permanent indentation modeling. A numerical model has been elaborated in order to simulate the different impact damage types developing during low velocity/low energy impact. The three current damage types: matrix cracking, fiber failure and delamination, are simulated. Inter-laminar damage, i.e. interface delamination, is conventionally simulated using interface elements based on fracture mechanics. Intra-laminar damage, i.e. matrix cracks, is simulated using interface elements based on failure criterion. Fiber failure is simulated using degradation in the volume elements. The originality of this model is to simulate permanent indentation after impact with a ‘‘plastic-like’’model introduced in the matrix cracking elements. This model type is based on experimental observations showing matrix cracking debris which block crack closure. Lastly, experimental validation is performed, which demonstrates the model’s satisfactory relevance in simulating impact damage. This acceptable match between experiment and modeling confirms the interest of the novel approach proposed in this paper to describe the physics behind permanent indentation
Cinematon #327: Jean-Christophe Bouvet
No full texthttps://researchrepository.wvu.edu/fixation-db-experimental-film/1815/thumbnail.jp
Reversible Rail Shear Apparatus Applied to the Study of Woven Laminate Shear Behavior
No full textThe multitude of in-plane shear tests existing in the literature seems to demonstrate the complexity of developing a test adapted to all experimental works. In a general framework of investigation of translaminar cracks in thin laminates, a test able to reproduce a pure in-plane shear loading was required. The laminate studied is notably employed as helicopter blade skin, and cyclic torsion induced by aerodynamic load involves cyclic in-plane shear. This particular application established some specifications for the test needed to carry out this study. To comply with them, an original technological solution has been developed from a three-rail shear test apparatus. This paper describes the resulting “reversible rail shear test” solution and its application to the study of in-plane shear behavior of a thin glass-epoxy laminate. The results concern plain and notched coupons under quasi-static loading, and crack growth tests under cyclic loading
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