Documents disponibles écrits par cet auteur

Analysis of snap-back instability due to end -plate debonding in strengthened beams / A. Carpinteri in Journal of engineering mechanics, Vol. 136 N° 2 (Fevrier 2010) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 136 N° 2 (Fevrier 2010) . - pp. 199-208 Titre : Analysis of snap-back instability due to end -plate debonding in strengthened beams Type de document : texte imprimé Auteurs : A. Carpinteri, Auteur ; Paggi, M., Auteur Article en page(s) : pp. 199-208 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Fiber  reinforced  polymers  Bonding  Cracking  Nonlinear  analysis  Finite  element  method  Beams  Plates. Résumé : The problem of end-plate debonding of the external reinforcement in strengthened concrete beams is analyzed in this paper. As experimentally observed, this mode of failure is highly brittle and poses severe limitations to the efficacy of the strengthening technique. A numerical analysis of the full-range behavior of strengthened beams in bending is herein proposed to study the stages of nucleation and propagation of interfacial cracks between the external reinforcement and the concrete substrate. This is achieved by modeling the nonlinear interface behavior according to a cohesive law accounting for Mode Mixity. The numerically obtained load versus midspan deflection curves for three- or four-point bending beams show that the process of end-plate debonding is the result of a snap-back instability, which is fully interpreted in the framework of the Catastrophe Theory. To capture the softening branch with positive slope, the interface crack-length control scheme is proposed in the numerical simulations. The results of a wide parametric study exploring the effect of the relative reinforcement length, the mechanical percentage of fiber-reinforced polymer sheets, the beam slenderness, and the ratio between Mode II and Mode I fracture energies are collected in useful diagrams. Finally, an experimental assessment of the proposed model completes the paper. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] Analysis of snap-back instability due to end -plate debonding in strengthened beams [texte imprimé] / A. Carpinteri, Auteur ; Paggi, M., Auteur . - pp. 199-208. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 136 N° 2 (Fevrier 2010) . - pp. 199-208 Mots-clés : Fiber  reinforced  polymers  Bonding  Cracking  Nonlinear  analysis  Finite  element  method  Beams  Plates. Résumé : The problem of end-plate debonding of the external reinforcement in strengthened concrete beams is analyzed in this paper. As experimentally observed, this mode of failure is highly brittle and poses severe limitations to the efficacy of the strengthening technique. A numerical analysis of the full-range behavior of strengthened beams in bending is herein proposed to study the stages of nucleation and propagation of interfacial cracks between the external reinforcement and the concrete substrate. This is achieved by modeling the nonlinear interface behavior according to a cohesive law accounting for Mode Mixity. The numerically obtained load versus midspan deflection curves for three- or four-point bending beams show that the process of end-plate debonding is the result of a snap-back instability, which is fully interpreted in the framework of the Catastrophe Theory. To capture the softening branch with positive slope, the interface crack-length control scheme is proposed in the numerical simulations. The results of a wide parametric study exploring the effect of the relative reinforcement length, the mechanical percentage of fiber-reinforced polymer sheets, the beam slenderness, and the ratio between Mode II and Mode I fracture energies are collected in useful diagrams. Finally, an experimental assessment of the proposed model completes the paper. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]

New model for the analysis of size-scale effects on the ductility of reinforced concrete elements in bending / A. Carpinteri in Journal of engineering mechanics, Vol. 135 N°3 (Mars 2009) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 135 N°3 (Mars 2009) . - pp. 221-229 Titre : New model for the analysis of size-scale effects on the ductility of reinforced concrete elements in bending Type de document : texte imprimé Auteurs : A. Carpinteri, Auteur ; M. Corrado, Auteur ; M. Paggi, Auteur Article en page(s) : pp. 221-229 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Reinforced  concrete  Ductility  Size  effect  Crushing  Nonlinear  analysis  Finite  element  method  Bending. Résumé : The well-known cohesive crack model describes strain localization with a softening stress variation in concrete members subjected to tension. An analogous behavior is also observed in compression, when strain localization takes place in a damaged zone and the stress reaches the compression strength with surface energy dissipation. In the present paper, we propose the new concept of overlapping crack model, which is analogous to the cohesive one and permits us to simulate material interpenetration due to crushing. The two aforementioned elementary models are merged into a more complex algorithm able to describe both cracking and crushing growths during loading processes in reinforced concrete members. A numerical procedure based on elastic coefficients is developed, taking into account the proposed constitutive laws in tension and compression. With this algorithm, it is possible to effectively capture the flexural behavior of reinforced concrete beams by varying the reinforcement percentage and/or the beam depth. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] New model for the analysis of size-scale effects on the ductility of reinforced concrete elements in bending [texte imprimé] / A. Carpinteri, Auteur ; M. Corrado, Auteur ; M. Paggi, Auteur . - pp. 221-229. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 135 N°3 (Mars 2009) . - pp. 221-229 Mots-clés : Reinforced  concrete  Ductility  Size  effect  Crushing  Nonlinear  analysis  Finite  element  method  Bending. Résumé : The well-known cohesive crack model describes strain localization with a softening stress variation in concrete members subjected to tension. An analogous behavior is also observed in compression, when strain localization takes place in a damaged zone and the stress reaches the compression strength with surface energy dissipation. In the present paper, we propose the new concept of overlapping crack model, which is analogous to the cohesive one and permits us to simulate material interpenetration due to crushing. The two aforementioned elementary models are merged into a more complex algorithm able to describe both cracking and crushing growths during loading processes in reinforced concrete members. A numerical procedure based on elastic coefficients is developed, taking into account the proposed constitutive laws in tension and compression. With this algorithm, it is possible to effectively capture the flexural behavior of reinforced concrete beams by varying the reinforcement percentage and/or the beam depth. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]