Documents disponibles écrits par cet auteur

Experimental study of Si–Al substitution in calcium-silicate-hydrate (C-S-H) prepared under equilibrium conditions / Xiaolin Pardal in Cement and concrete research, Vol. 39 N° 8 (Août 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 8 (Août 2009) . - pp. 637–643 Titre : Experimental study of Si–Al substitution in calcium-silicate-hydrate (C-S-H) prepared under equilibrium conditions Type de document : texte imprimé Auteurs : Xiaolin Pardal, Auteur ; Isabelle Pochard, Auteur Année de publication : 2009 Article en page(s) : pp. 637–643 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Calcium-silicate-hydrate  (C-S-H);  Aluminium;  Thermodynamic  equilibria;  Chemistry Résumé : C-A-S-H of varying Al/Si and Ca/(Al + Si) ratios have been prepared introducing C-S-H (Ca/Si = 0.66 and 0.95) at different weight concentrations in a solution coming from the hydration of tricalcium aluminate (Ca3Al2O6) in water. XRD and EDX (TEM) analyses show that using this typical synthesise procedure, pure C-A-S-H is obtained only for calcium hydroxide concentrations below 4.5 mmol L− 1. Otherwise, calcium carboaluminate or strätlingite is also present beside C-A-S-H. The tobermorite-like structure is maintained for C-A-S-H. A kinetic study has shown that the formation of C-A-S-H is a fast reaction, typically less than a few hours. The Ca/(Al + Si) ratio of C-A-S-H matches the Ca/Si ratio of the initial C-S-H, in the ionic concentration range studied i.e., less than 4.5 and 3 mmol L− 1 of calcium hydroxide and aluminium hydroxide respectively. The Al/Si ratio increases with the aluminium concentration in the solution and reaches a maximum value of 0.19. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S000888460900091X [article] Experimental study of Si–Al substitution in calcium-silicate-hydrate (C-S-H) prepared under equilibrium conditions [texte imprimé] / Xiaolin Pardal, Auteur ; Isabelle Pochard, Auteur . - 2009 . - pp. 637–643. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 8 (Août 2009) . - pp. 637–643 Mots-clés : Calcium-silicate-hydrate  (C-S-H);  Aluminium;  Thermodynamic  equilibria;  Chemistry Résumé : C-A-S-H of varying Al/Si and Ca/(Al + Si) ratios have been prepared introducing C-S-H (Ca/Si = 0.66 and 0.95) at different weight concentrations in a solution coming from the hydration of tricalcium aluminate (Ca3Al2O6) in water. XRD and EDX (TEM) analyses show that using this typical synthesise procedure, pure C-A-S-H is obtained only for calcium hydroxide concentrations below 4.5 mmol L− 1. Otherwise, calcium carboaluminate or strätlingite is also present beside C-A-S-H. The tobermorite-like structure is maintained for C-A-S-H. A kinetic study has shown that the formation of C-A-S-H is a fast reaction, typically less than a few hours. The Ca/(Al + Si) ratio of C-A-S-H matches the Ca/Si ratio of the initial C-S-H, in the ionic concentration range studied i.e., less than 4.5 and 3 mmol L− 1 of calcium hydroxide and aluminium hydroxide respectively. The Al/Si ratio increases with the aluminium concentration in the solution and reaches a maximum value of 0.19. ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S000888460900091X