Documents disponibles écrits par cet auteur

Contribution of granular interactions to self compacting concrete stability: Development of a new device / S. Bethmont in Cement and concrete research, Vol. 39 N° 1 (Janvier 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 1 (Janvier 2009) . - pp. 30–35 Titre : Contribution of granular interactions to self compacting concrete stability: Development of a new device Type de document : texte imprimé Auteurs : S. Bethmont, Auteur ; L. D'Aloia Schwartzentruber, Auteur ; C. E. Stefani, Auteur Année de publication : 2009 Article en page(s) : pp. 30–35 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Rheology;  Cement  paste;  Aggregate;  Concrete;  Self  Compacting  Concrete  (SCC) Résumé : Understanding the SCC behaviour is essential for resolving placement and consolidation problems in the field. As far as segregation is concerned, one of the main remaining obstacles is the design of a concrete mixture suitable for given casting conditions. Physical approaches which consist in studying the sedimentation of a single particle in a yield stress fluid failed to describe SCC static segregation. Segregation is a more complex phenomenon and the interactions between coarse aggregates have to be taken into account. They contribute to the stability of fresh SCC and this contribution should only depend on the solid fraction of the granular skeleton. A new experimental device has been developed in order to highlight and quantify the combined effects of coarse aggregates. This device allows studying lattices of particles. These latter are organised according to a cubic centred pattern and are immersed in a yield stress fluid. The experimental device and the test procedure are described in this paper. The validity of measurements has been demonstrated by performing a first series of tests and numerical simulations. Repeatability is quite satisfactory and “wall effects” can be limited. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884608001956 [article] Contribution of granular interactions to self compacting concrete stability: Development of a new device [texte imprimé] / S. Bethmont, Auteur ; L. D'Aloia Schwartzentruber, Auteur ; C. E. Stefani, Auteur . - 2009 . - pp. 30–35. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 1 (Janvier 2009) . - pp. 30–35 Mots-clés : Rheology;  Cement  paste;  Aggregate;  Concrete;  Self  Compacting  Concrete  (SCC) Résumé : Understanding the SCC behaviour is essential for resolving placement and consolidation problems in the field. As far as segregation is concerned, one of the main remaining obstacles is the design of a concrete mixture suitable for given casting conditions. Physical approaches which consist in studying the sedimentation of a single particle in a yield stress fluid failed to describe SCC static segregation. Segregation is a more complex phenomenon and the interactions between coarse aggregates have to be taken into account. They contribute to the stability of fresh SCC and this contribution should only depend on the solid fraction of the granular skeleton. A new experimental device has been developed in order to highlight and quantify the combined effects of coarse aggregates. This device allows studying lattices of particles. These latter are organised according to a cubic centred pattern and are immersed in a yield stress fluid. The experimental device and the test procedure are described in this paper. The validity of measurements has been demonstrated by performing a first series of tests and numerical simulations. Repeatability is quite satisfactory and “wall effects” can be limited. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S0008884608001956