Documents disponibles écrits par cet auteur

Comparing numerical and experimental approaches for the stochastic modeling of the bouncing of a boulder on a coarse soil / Franck Bourrier in European journal of environmental and civil engineering, Vol. 14 N° 1 (Janvier 2010) 

Public ISBD [article]  in European journal of environmental and civil engineering > Vol. 14 N° 1 (Janvier 2010) . - pp. 87-111 Titre : Comparing numerical and experimental approaches for the stochastic modeling of the bouncing of a boulder on a coarse soil Type de document : texte imprimé Auteurs : Franck Bourrier, Auteur ; Nicot, François, Auteur ; Nicolas Eckert, Auteur Année de publication : 2010 Article en page(s) : pp. 87-111 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Rockfall  hazard  Impact  Discrete  element  method  Stochastic  Trajectory  analysis Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This paper proposes numerical investigations for the stochastic modeling of a boulder impacting a coarse granular soil. The soil is considered as a noncohesive granular medium using a discrete element method and the soil model is calibrated compared to results from half-scale experiments. Based on this numerical model, an extensive numerical simulation campaign is carried out. The statistical analysis of the numerical results allows the definition of a stochastic bouncing model that quantifies most of the variability of the numerical results. Comparisons with classical bouncing models in the field of trajectory analysis highlight that this model expands classical approaches. The comparison of results from real-scale experiments to trajectory simulations based on the stochastic model show the relevance of the proposed approach to modeling rockfall trajectories. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/resnum.jsp [article] Comparing numerical and experimental approaches for the stochastic modeling of the bouncing of a boulder on a coarse soil [texte imprimé] / Franck Bourrier, Auteur ; Nicot, François, Auteur ; Nicolas Eckert, Auteur . - 2010 . - pp. 87-111. Génie Civil Langues : Anglais (eng) in European journal of environmental and civil engineering > Vol. 14 N° 1 (Janvier 2010) . - pp. 87-111 Mots-clés : Rockfall  hazard  Impact  Discrete  element  method  Stochastic  Trajectory  analysis Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This paper proposes numerical investigations for the stochastic modeling of a boulder impacting a coarse granular soil. The soil is considered as a noncohesive granular medium using a discrete element method and the soil model is calibrated compared to results from half-scale experiments. Based on this numerical model, an extensive numerical simulation campaign is carried out. The statistical analysis of the numerical results allows the definition of a stochastic bouncing model that quantifies most of the variability of the numerical results. Comparisons with classical bouncing models in the field of trajectory analysis highlight that this model expands classical approaches. The comparison of results from real-scale experiments to trajectory simulations based on the stochastic model show the relevance of the proposed approach to modeling rockfall trajectories. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/resnum.jsp

European journal of environmental and civil engineering / Di Pisco, Marco 

Public ISBD [périodique]  Voir les bulletins disponibles Rechercher dans ce périodique  Titre : European journal of environmental and civil engineering : revue européenne de génie civil Type de document : texte imprimé Auteurs : Di Pisco, Marco, Directeur de publication, rédacteur en chef ; La Borderie, Christian, Editeur scientifique ; Nicot, François, Editeur scientifique Editeur : Paris [France] : Lavoisier Année de publication : 2008- ISBN/ISSN/EAN : 1964-8189 Note générale : Périodicité : Bimestrielle 2010-2012 Langues : Français (fre) Mots-clés : Génie  civil  ;  Technique  de  l'environnement Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes DEWEY : 624 En ligne : http://www.ejece.revuesonline.com [périodique]  Voir les bulletins disponibles Rechercher dans ce périodique European journal of environmental and civil engineering : revue européenne de génie civil [texte imprimé] / Di Pisco, Marco, Directeur de publication, rédacteur en chef ; La Borderie, Christian, Editeur scientifique ; Nicot, François, Editeur scientifique . - Paris (France) : Lavoisier, 2008-. ISSN : 1964-8189 Périodicité : Bimestrielle 2010-2012 Langues : Français (fre) Mots-clés : Génie  civil  ;  Technique  de  l'environnement Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes DEWEY : 624 En ligne : http://www.ejece.revuesonline.com

Micromechanical formulation of stress dilatancy as a flow rule in plasticity of granular materials / Wan, Richard in Journal of engineering mechanics, Vol. 136 N° 5 (Mai 2010) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 136 N° 5 (Mai 2010) . - pp. 589-598 Titre : Micromechanical formulation of stress dilatancy as a flow rule in plasticity of granular materials Type de document : texte imprimé Auteurs : Wan, Richard, Auteur ; Nicot, François, Auteur ; Darve, Félix, Auteur Article en page(s) : pp. 589-598 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Elastoplasticity  Granular  media  Discrete  elements  Micromechanics  Dilatancy. Résumé : The paper presents micromechanical formulations of stress dilatancy and their connection to a flow rule in classical elastoplasticity. Dilatancy is inarguably the manifestation of an internal kinematic constraint involving both particle shape and connectivity (texture or fabric) with operative interparticle friction against applied stresses. However, this notion of microstructural dependence is nonexistent in most stress-dilatancy formulations in the literature. We present two different micromechanical approaches that arrive at stress-dilatancy expressions with embedded micromechanical information in the form of a second-order fabric tensor. In connection to stress dilatancy, the underlying nature of the flow rule is next discussed with respect to the dependence of the plastic strain increment vector on the direction of loading (stress increment). It is demonstrated analytically that the flow rule is singular in three-dimensional stress and strain conditions. Finally, the dependencies of dilatancy on fabric are illustrated through various numerical simulations using the micromechanically enriched stress-dilatancy models and a discrete element method. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=ASCERL&CURRENT=null [...] [article] Micromechanical formulation of stress dilatancy as a flow rule in plasticity of granular materials [texte imprimé] / Wan, Richard, Auteur ; Nicot, François, Auteur ; Darve, Félix, Auteur . - pp. 589-598. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 136 N° 5 (Mai 2010) . - pp. 589-598 Mots-clés : Elastoplasticity  Granular  media  Discrete  elements  Micromechanics  Dilatancy. Résumé : The paper presents micromechanical formulations of stress dilatancy and their connection to a flow rule in classical elastoplasticity. Dilatancy is inarguably the manifestation of an internal kinematic constraint involving both particle shape and connectivity (texture or fabric) with operative interparticle friction against applied stresses. However, this notion of microstructural dependence is nonexistent in most stress-dilatancy formulations in the literature. We present two different micromechanical approaches that arrive at stress-dilatancy expressions with embedded micromechanical information in the form of a second-order fabric tensor. In connection to stress dilatancy, the underlying nature of the flow rule is next discussed with respect to the dependence of the plastic strain increment vector on the direction of loading (stress increment). It is demonstrated analytically that the flow rule is singular in three-dimensional stress and strain conditions. Finally, the dependencies of dilatancy on fabric are illustrated through various numerical simulations using the micromechanically enriched stress-dilatancy models and a discrete element method. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=ASCERL&CURRENT=null [...]

Snow mechanics applied to avalanche risk mitigation / Nicot, François in European journal of environmental and civil engineering, Vol. 15 N° Spécial (Septembre 2011) 

Public ISBD [article]  in European journal of environmental and civil engineering > Vol. 15 N° Spécial (Septembre 2011) . - pp. 15-30 Titre : Snow mechanics applied to avalanche risk mitigation Titre original : Mécanique de la neige appliquée au génie par avalanche Type de document : texte imprimé Auteurs : Nicot, François, Auteur Année de publication : 2012 Article en page(s) : pp. 15-30 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Micro-mechanics  Snow  Micro-structure  Homogenization  Discrete  elements  Cables  structures  Mechanical  interaction  Structure  design Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : The snow avalanche risk is usually mitigated by means of specific structures set up in triggering zones. These structures are designed in order to prevent avalanches from occurring. Thus, a description of the mechanisms governing the interaction between the snow mantel and the structure is required. For this purpose, the complexity of the snow material, made up of an assembly of contacting ice grains, should be accounted for. This paper aims at presenting a multiscale approach, leading to the implementation of a micro-mechanical model of snow within a Lagrangian-discrete numerical code describing the behavior of the structure. Both intra- and inter-granular deformation mechanisms in the snow material are considered. Then, after a discussion on the different scales of interest, and on how they are connected, the results of numerical simulations are finally commented in order to emphasize the capability of the numerical tool developed for engineering purposes. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/article.jsp?articleId=16584 [article] Snow mechanics applied to avalanche risk mitigation = Mécanique de la neige appliquée au génie par avalanche [texte imprimé] / Nicot, François, Auteur . - 2012 . - pp. 15-30. Génie Civil Langues : Anglais (eng) in European journal of environmental and civil engineering > Vol. 15 N° Spécial (Septembre 2011) . - pp. 15-30 Mots-clés : Micro-mechanics  Snow  Micro-structure  Homogenization  Discrete  elements  Cables  structures  Mechanical  interaction  Structure  design Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : The snow avalanche risk is usually mitigated by means of specific structures set up in triggering zones. These structures are designed in order to prevent avalanches from occurring. Thus, a description of the mechanisms governing the interaction between the snow mantel and the structure is required. For this purpose, the complexity of the snow material, made up of an assembly of contacting ice grains, should be accounted for. This paper aims at presenting a multiscale approach, leading to the implementation of a micro-mechanical model of snow within a Lagrangian-discrete numerical code describing the behavior of the structure. Both intra- and inter-granular deformation mechanisms in the snow material are considered. Then, after a discussion on the different scales of interest, and on how they are connected, the results of numerical simulations are finally commented in order to emphasize the capability of the numerical tool developed for engineering purposes. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/article.jsp?articleId=16584