Documents disponibles écrits par cet auteur

Finite-element modeling to calculate the overall stiffness of cracked reinforced concrete beams / Arnaud Castel in Journal of structural engineering, Vol. 138 N° 7 (Juillet 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 889–898 Titre : Finite-element modeling to calculate the overall stiffness of cracked reinforced concrete beams Type de document : texte imprimé Auteurs : Arnaud Castel, Auteur ; Thierry Vidal, Auteur ; Raoul François, Auteur Année de publication : 2012 Article en page(s) : pp. 889–898 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Reinforced  Concrete  Tension  stiffening  Bond  Serviceability  FE  model Résumé : The macro-finite-element (MFE) modeling proposed in this paper is dedicated to the calculation of the deflection of already cracked reinforced concrete beams under service loading at the stabilized cracking stage. MFEs are beam finite elements, characterized by their average moment of inertia, calculated using nonlinear assumed distributions of steel strain, concrete strain, and neutral axis between two consecutive bending cracks. The results of the MFE model are successfully compared with experiments performed on five RC beams, including square- and T-section beams and two concretes (grades 30 and 40 MPa). A successful application of the MFE method to a statically indeterminate beam is also presented. The MFE modeling is appealing for use in practice because of its computational simplicity. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000520 [article] Finite-element modeling to calculate the overall stiffness of cracked reinforced concrete beams [texte imprimé] / Arnaud Castel, Auteur ; Thierry Vidal, Auteur ; Raoul François, Auteur . - 2012 . - pp. 889–898. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 889–898 Mots-clés : Reinforced  Concrete  Tension  stiffening  Bond  Serviceability  FE  model Résumé : The macro-finite-element (MFE) modeling proposed in this paper is dedicated to the calculation of the deflection of already cracked reinforced concrete beams under service loading at the stabilized cracking stage. MFEs are beam finite elements, characterized by their average moment of inertia, calculated using nonlinear assumed distributions of steel strain, concrete strain, and neutral axis between two consecutive bending cracks. The results of the MFE model are successfully compared with experiments performed on five RC beams, including square- and T-section beams and two concretes (grades 30 and 40 MPa). A successful application of the MFE method to a statically indeterminate beam is also presented. The MFE modeling is appealing for use in practice because of its computational simplicity. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000520

Structural performance of a 26-year-old corroded reinforced concrete beam / Inamullah Khan in European journal of environmental and civil engineering, Vol. 16 N° 3-4 (Mars/Avril 2012) 

Public ISBD [article]  in European journal of environmental and civil engineering > Vol. 16 N° 3-4 (Mars/Avril 2012) . - pp. 440-449 Titre : Structural performance of a 26-year-old corroded reinforced concrete beam Type de document : texte imprimé Auteurs : Inamullah Khan, Auteur ; Raoul François, Auteur ; Arnaud Castel, Auteur Année de publication : 2012 Article en page(s) : pp. 440-449 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Corrosion  Reinforced  concrete  Load-bearing  capacity  Stiffness  Ductility  Chloride Résumé : This article presents experimental results and the modelling of a highly corroded beam subjected to a chloride environment to assess the performance of long-term-corrosion-damaged beams. A reinforced concrete beam corroded by 26 years of exposure to a chloride environment was tested until failure, as was a control beam of the same age. Cracking maps and corrosion maps were drawn for the corroded beam. Force displacement curves for both beams and stress strain curves for the steel bars were also plotted. From the results it appears that corrosion has a significant impact on the load carrying capacity, stiffness and deflection of beams. The modelling approach using Macro Finite Element (MFE) shows good agreement with experimental results in terms of load capacity, stiffness of the beam and ultimate deflection. DEWEY : 624 ISSN : 1964-8189 En ligne : http://www.tandfonline.com/doi/abs/10.1080/19648189.2012.667992 [article] Structural performance of a 26-year-old corroded reinforced concrete beam [texte imprimé] / Inamullah Khan, Auteur ; Raoul François, Auteur ; Arnaud Castel, Auteur . - 2012 . - pp. 440-449. Génie Civil Langues : Anglais (eng) in European journal of environmental and civil engineering > Vol. 16 N° 3-4 (Mars/Avril 2012) . - pp. 440-449 Mots-clés : Corrosion  Reinforced  concrete  Load-bearing  capacity  Stiffness  Ductility  Chloride Résumé : This article presents experimental results and the modelling of a highly corroded beam subjected to a chloride environment to assess the performance of long-term-corrosion-damaged beams. A reinforced concrete beam corroded by 26 years of exposure to a chloride environment was tested until failure, as was a control beam of the same age. Cracking maps and corrosion maps were drawn for the corroded beam. Force displacement curves for both beams and stress strain curves for the steel bars were also plotted. From the results it appears that corrosion has a significant impact on the load carrying capacity, stiffness and deflection of beams. The modelling approach using Macro Finite Element (MFE) shows good agreement with experimental results in terms of load capacity, stiffness of the beam and ultimate deflection. DEWEY : 624 ISSN : 1964-8189 En ligne : http://www.tandfonline.com/doi/abs/10.1080/19648189.2012.667992

Study of the impact of localised cracks on the corrosion mechanism / Raoul François in European journal of environmental and civil engineering, Vol. 16 N° 3-4 (Mars/Avril 2012) 

Public ISBD [article]  in European journal of environmental and civil engineering > Vol. 16 N° 3-4 (Mars/Avril 2012) . - pp. 392-401 Titre : Study of the impact of localised cracks on the corrosion mechanism Type de document : texte imprimé Auteurs : Raoul François, Auteur ; Inamullah Khan, Auteur ; Ngoc Anh Vu, Auteur Année de publication : 2012 Article en page(s) : pp. 392-401 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Corrosion  Steel  bars  Cracks  Chloride Résumé : Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. Much research has been carried out to investigate the influence of cracks on rebar corrosion. In this project ring shaped mortar samples with an 8mm steel bar inside were cracked with different crack widths and then subjected to continuous wetting and drying cycles in salt solution having 35 g/L of NaCl, to accelerate the corrosion process in laboratory conditions. The samples were broken after 1.5 years and 2.5 years to observe the corrosion pattern. Results show that cracks whatever their width allow the corrosion onset at the bottom of cracks and along the steel–concrete interface damaged zone caused by the creation of cracks. This process leads to corrosion cracks formation time dependant of the crack opening, which modify the environmental conditions at the level of steel leading to the generalisation of corrosion all along the re-bars. DEWEY : 624 ISSN : 1964-8189 En ligne : http://www.tandfonline.com/doi/abs/10.1080/19648189.2012.667982 [article] Study of the impact of localised cracks on the corrosion mechanism [texte imprimé] / Raoul François, Auteur ; Inamullah Khan, Auteur ; Ngoc Anh Vu, Auteur . - 2012 . - pp. 392-401. Génie Civil Langues : Anglais (eng) in European journal of environmental and civil engineering > Vol. 16 N° 3-4 (Mars/Avril 2012) . - pp. 392-401 Mots-clés : Corrosion  Steel  bars  Cracks  Chloride Résumé : Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. Much research has been carried out to investigate the influence of cracks on rebar corrosion. In this project ring shaped mortar samples with an 8mm steel bar inside were cracked with different crack widths and then subjected to continuous wetting and drying cycles in salt solution having 35 g/L of NaCl, to accelerate the corrosion process in laboratory conditions. The samples were broken after 1.5 years and 2.5 years to observe the corrosion pattern. Results show that cracks whatever their width allow the corrosion onset at the bottom of cracks and along the steel–concrete interface damaged zone caused by the creation of cracks. This process leads to corrosion cracks formation time dependant of the crack opening, which modify the environmental conditions at the level of steel leading to the generalisation of corrosion all along the re-bars. DEWEY : 624 ISSN : 1964-8189 En ligne : http://www.tandfonline.com/doi/abs/10.1080/19648189.2012.667982

The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment / Ruijin Zhang in Cement and concrete research, Vol. 39 N° 11 (Novembre 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1077–1086 Titre : The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment Type de document : texte imprimé Auteurs : Ruijin Zhang, Auteur ; Arnaud Castel, Auteur ; Raoul François, Auteur Année de publication : 2010 Article en page(s) : pp. 1077–1086 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Crack  Detection  ;Corrosion  ;Long-Term  Performance  ;  Bond  Strength  ;  Reinforcement Résumé : This paper deals with two corroded reinforcement concrete beams, which have been stored under sustained load in a chloride environment for 14 and 23 years respectively. The evolution of corrosion pattern of reinforcement and its influence on serviceability are studied. In chloride-induced corrosion process, corrosion cracking affects significantly the corrosion pattern. During the corrosion cracking initiation period, only local pitting corrosion occurs. At early stage of cracking propagation, localized pitting corrosion is still predominant as cracks widths are very small and cracks are not interconnected, but a general corrosion slowly develops as the cracks widen. At late cracking stage, interconnected cracking with wide width develops along large parts of the beam leading to a general corrosion pattern. Macrocells and microcells concepts are used for the interpretation of the results. Mechanical experiments and corrosion simulation tests are performed to clarify the influence of this corrosion pattern evolution on the serviceability of the beams (deflection increase). Experimental results show that, when the corrosion is localized (early cracking stage), the steel–concrete bond loss is the main factor affecting the beams serviceability. The local cross-section loss resulting from pitting attack does not significantly influence the deflection of the beam. When corrosion is generalized (late cracking stage), as the steel–concrete bond is already lost, the generalized steel cross-section reduction becomes the main factor affecting the beams serviceability. But, at this stage, the deflection increase is slower due to the low general corrosion rate. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609001860 [article] The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment [texte imprimé] / Ruijin Zhang, Auteur ; Arnaud Castel, Auteur ; Raoul François, Auteur . - 2010 . - pp. 1077–1086. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1077–1086 Mots-clés : Crack  Detection  ;Corrosion  ;Long-Term  Performance  ;  Bond  Strength  ;  Reinforcement Résumé : This paper deals with two corroded reinforcement concrete beams, which have been stored under sustained load in a chloride environment for 14 and 23 years respectively. The evolution of corrosion pattern of reinforcement and its influence on serviceability are studied. In chloride-induced corrosion process, corrosion cracking affects significantly the corrosion pattern. During the corrosion cracking initiation period, only local pitting corrosion occurs. At early stage of cracking propagation, localized pitting corrosion is still predominant as cracks widths are very small and cracks are not interconnected, but a general corrosion slowly develops as the cracks widen. At late cracking stage, interconnected cracking with wide width develops along large parts of the beam leading to a general corrosion pattern. Macrocells and microcells concepts are used for the interpretation of the results. Mechanical experiments and corrosion simulation tests are performed to clarify the influence of this corrosion pattern evolution on the serviceability of the beams (deflection increase). Experimental results show that, when the corrosion is localized (early cracking stage), the steel–concrete bond loss is the main factor affecting the beams serviceability. The local cross-section loss resulting from pitting attack does not significantly influence the deflection of the beam. When corrosion is generalized (late cracking stage), as the steel–concrete bond is already lost, the generalized steel cross-section reduction becomes the main factor affecting the beams serviceability. But, at this stage, the deflection increase is slower due to the low general corrosion rate. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609001860

The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment / Ruijin Zhang in Cement and concrete research, Vol. 39 N° 11 (Novembre 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1077–1086 Titre : The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment Type de document : texte imprimé Auteurs : Ruijin Zhang, Auteur ; Arnaud Castel, Auteur ; Raoul François, Auteur Année de publication : 2010 Article en page(s) : pp. 1077–1086 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Crack  Detection  ;  Corrosion  ;  Long-Term  Performance  ;  Bond  Strength  ;  Reinforcement Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : This paper deals with two corroded reinforcement concrete beams, which have been stored under sustained load in a chloride environment for 14 and 23 years respectively. The evolution of corrosion pattern of reinforcement and its influence on serviceability are studied. In chloride-induced corrosion process, corrosion cracking affects significantly the corrosion pattern. During the corrosion cracking initiation period, only local pitting corrosion occurs. At early stage of cracking propagation, localized pitting corrosion is still predominant as cracks widths are very small and cracks are not interconnected, but a general corrosion slowly develops as the cracks widen. At late cracking stage, interconnected cracking with wide width develops along large parts of the beam leading to a general corrosion pattern. Macrocells and microcells concepts are used for the interpretation of the results. Mechanical experiments and corrosion simulation tests are performed to clarify the influence of this corrosion pattern evolution on the serviceability of the beams (deflection increase). Experimental results show that, when the corrosion is localized (early cracking stage), the steel–concrete bond loss is the main factor affecting the beams serviceability. The local cross-section loss resulting from pitting attack does not significantly influence the deflection of the beam. When corrosion is generalized (late cracking stage), as the steel–concrete bond is already lost, the generalized steel cross-section reduction becomes the main factor affecting the beams serviceability. But, at this stage, the deflection increase is slower due to the low general corrosion rate. REFERENCE : 0008-8846 DEWEY : 620.13 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609001860 [article] The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment [texte imprimé] / Ruijin Zhang, Auteur ; Arnaud Castel, Auteur ; Raoul François, Auteur . - 2010 . - pp. 1077–1086. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1077–1086 Mots-clés : Crack  Detection  ;  Corrosion  ;  Long-Term  Performance  ;  Bond  Strength  ;  Reinforcement Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : This paper deals with two corroded reinforcement concrete beams, which have been stored under sustained load in a chloride environment for 14 and 23 years respectively. The evolution of corrosion pattern of reinforcement and its influence on serviceability are studied. In chloride-induced corrosion process, corrosion cracking affects significantly the corrosion pattern. During the corrosion cracking initiation period, only local pitting corrosion occurs. At early stage of cracking propagation, localized pitting corrosion is still predominant as cracks widths are very small and cracks are not interconnected, but a general corrosion slowly develops as the cracks widen. At late cracking stage, interconnected cracking with wide width develops along large parts of the beam leading to a general corrosion pattern. Macrocells and microcells concepts are used for the interpretation of the results. Mechanical experiments and corrosion simulation tests are performed to clarify the influence of this corrosion pattern evolution on the serviceability of the beams (deflection increase). Experimental results show that, when the corrosion is localized (early cracking stage), the steel–concrete bond loss is the main factor affecting the beams serviceability. The local cross-section loss resulting from pitting attack does not significantly influence the deflection of the beam. When corrosion is generalized (late cracking stage), as the steel–concrete bond is already lost, the generalized steel cross-section reduction becomes the main factor affecting the beams serviceability. But, at this stage, the deflection increase is slower due to the low general corrosion rate. REFERENCE : 0008-8846 DEWEY : 620.13 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609001860