Documents disponibles écrits par cet auteur

Chemo–mechanical modeling for prediction of alkali silica reaction (ASR) expansion / Stéphane Multon in Cement and concrete research, Vol. 39 N° 6 (Juin 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 6 (Juin 2009) . - pp. Martin Cyr Titre : Chemo–mechanical modeling for prediction of alkali silica reaction (ASR) expansion Type de document : texte imprimé Auteurs : Stéphane Multon, Auteur ; Alain Sellier, Auteur ; Martin Cyr, Auteur Année de publication : 2009 Article en page(s) : pp. Martin Cyr Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Alkali-silica  reaction  (ASR);  Particle  size;  Alkali  content;  Expansion;  Model Résumé : The effect of the size of the aggregate on ASR expansion has already been well illustrated. This paper presents a microscopic model to analyze the development of ASR expansion of mortars containing reactive aggregate of different sizes. The attack of the reactive silica by alkali was determined through the mass balance equation, which controls the diffusion mechanism in the aggregate and the fixation of the alkali in the ASR gels. The mechanical part of the model is based on the damage theory in order to assess the decrease of stiffness of the mortar due to cracking caused by ASR and to calculate the expansion of a Representative Elementary Volume (REV) of concrete. Parameters of the model were estimated by curve fitting the expansions of four experimental mortars. The paper shows that the decrease of expansion with the size of the aggregate and the increase of the expansion with the alkali content are reproduced by the model, which is able to predict the expansions of six other mortars containing two sizes of reactive aggregate and cast with two alkali contents. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609000702 [article] Chemo–mechanical modeling for prediction of alkali silica reaction (ASR) expansion [texte imprimé] / Stéphane Multon, Auteur ; Alain Sellier, Auteur ; Martin Cyr, Auteur . - 2009 . - pp. Martin Cyr. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 6 (Juin 2009) . - pp. Martin Cyr Mots-clés : Alkali-silica  reaction  (ASR);  Particle  size;  Alkali  content;  Expansion;  Model Résumé : The effect of the size of the aggregate on ASR expansion has already been well illustrated. This paper presents a microscopic model to analyze the development of ASR expansion of mortars containing reactive aggregate of different sizes. The attack of the reactive silica by alkali was determined through the mass balance equation, which controls the diffusion mechanism in the aggregate and the fixation of the alkali in the ASR gels. The mechanical part of the model is based on the damage theory in order to assess the decrease of stiffness of the mortar due to cracking caused by ASR and to calculate the expansion of a Representative Elementary Volume (REV) of concrete. Parameters of the model were estimated by curve fitting the expansions of four experimental mortars. The paper shows that the decrease of expansion with the size of the aggregate and the increase of the expansion with the alkali content are reproduced by the model, which is able to predict the expansions of six other mortars containing two sizes of reactive aggregate and cast with two alkali contents. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609000702

Effects of aggregate size and alkali content on ASR expansion / Stéphane Multon in Cement and concrete research, Vol. 40 N° 4 (Avril 2010) 

Public ISBD [article]  in Cement and concrete research > Vol. 40 N° 4 (Avril 2010) . - pp. 508–516 Titre : Effects of aggregate size and alkali content on ASR expansion Type de document : texte imprimé Auteurs : Stéphane Multon, Auteur Année de publication : 2012 Article en page(s) : pp. 508–516 Note générale : Bibliogr. Langues : Anglais (eng) Mots-clés : Particle  size  distribution  ;  Alkali-aggregate  reaction  ;  Alkalis  ;  Modeling  ;  Pessimum  of  aggregate  size Résumé : Attempts to model ASR expansion are usually limited by the difficulty of taking into account the heterogeneous nature and size range of reactive aggregates. This work is a part of an overall project aimed at developing models to predict the potential expansion of concrete containing alkali-reactive aggregates. The paper gives measurements in order to provide experimental data concerning the effect of particle size of an alkali-reactive siliceous limestone on mortar expansion. Results show that no expansion was measured on the mortars using small particles (under 80 µm) while the coarse particles (0.63–1.25 mm) gave the largest expansions (0.33%). When two sizes of aggregate were used, ASR-expansions decreased with the proportion of small particles. Models are proposed to study correlations between the measured expansions and parameters such as the size of aggregates and the alkali and reactive silica contents. The pessimum effect of reactive aggregate size is assessed and the consequences on accelerated laboratory tests are discussed. En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609002038 [article] Effects of aggregate size and alkali content on ASR expansion [texte imprimé] / Stéphane Multon, Auteur . - 2012 . - pp. 508–516. Bibliogr. Langues : Anglais (eng) in Cement and concrete research > Vol. 40 N° 4 (Avril 2010) . - pp. 508–516 Mots-clés : Particle  size  distribution  ;  Alkali-aggregate  reaction  ;  Alkalis  ;  Modeling  ;  Pessimum  of  aggregate  size Résumé : Attempts to model ASR expansion are usually limited by the difficulty of taking into account the heterogeneous nature and size range of reactive aggregates. This work is a part of an overall project aimed at developing models to predict the potential expansion of concrete containing alkali-reactive aggregates. The paper gives measurements in order to provide experimental data concerning the effect of particle size of an alkali-reactive siliceous limestone on mortar expansion. Results show that no expansion was measured on the mortars using small particles (under 80 µm) while the coarse particles (0.63–1.25 mm) gave the largest expansions (0.33%). When two sizes of aggregate were used, ASR-expansions decreased with the proportion of small particles. Models are proposed to study correlations between the measured expansions and parameters such as the size of aggregates and the alkali and reactive silica contents. The pessimum effect of reactive aggregate size is assessed and the consequences on accelerated laboratory tests are discussed. En ligne : http://www.sciencedirect.com/science/article/pii/S0008884609002038

A review of continuum damage modelling for dam analysis / Eric Bourdarot in European journal of environmental and civil engineering, Vol. 14 N° 6-7 (Juin 2010) 

Public ISBD [article]  in European journal of environmental and civil engineering > Vol. 14 N° 6-7 (Juin 2010) . - pp. 805-822 Titre : A review of continuum damage modelling for dam analysis : Main steps of a fruitful university-industry collaboration leading to an integrated model applicable to AAR affected structures Type de document : texte imprimé Auteurs : Eric Bourdarot, Auteur ; Alain Sellier, Auteur ; Stéphane Multon, Auteur Année de publication : 2011 Article en page(s) : pp. 805-822 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Dam  Concrete  Damage  Swelling  Modelling  Alkali-aggregate  reactions Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This article presents the different steps of a research process initiated in the field of dam engineering, through collaboration between EDF and ENS Cachan, following Jacky Mazars' pioneering work on the application of the damage concept to concrete structure modelling. Considering the importance of concrete swelling phenomena for the long-term behaviour of concrete dams, special efforts have been devoted to the development of a rheologic model in this field. This paper explains how the research performed contributed to the elaboration and the justification of the main equations included. An application to the Temple-sur-Lot dam is presented. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/resnum.jsp [article] A review of continuum damage modelling for dam analysis : Main steps of a fruitful university-industry collaboration leading to an integrated model applicable to AAR affected structures [texte imprimé] / Eric Bourdarot, Auteur ; Alain Sellier, Auteur ; Stéphane Multon, Auteur . - 2011 . - pp. 805-822. Génie Civil Langues : Anglais (eng) in European journal of environmental and civil engineering > Vol. 14 N° 6-7 (Juin 2010) . - pp. 805-822 Mots-clés : Dam  Concrete  Damage  Swelling  Modelling  Alkali-aggregate  reactions Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : This article presents the different steps of a research process initiated in the field of dam engineering, through collaboration between EDF and ENS Cachan, following Jacky Mazars' pioneering work on the application of the damage concept to concrete structure modelling. Considering the importance of concrete swelling phenomena for the long-term behaviour of concrete dams, special efforts have been devoted to the development of a rheologic model in this field. This paper explains how the research performed contributed to the elaboration and the justification of the main equations included. An application to the Temple-sur-Lot dam is presented. DEWEY : 624 ISSN : 1964-8189 En ligne : http://ejece.revuesonline.com/resnum.jsp