| Titre : | Experimental study of Si–Al substitution in calcium-silicate-hydrate (C-S-H) prepared under equilibrium conditions (2009) |
| Auteurs : | Xiaolin Pardal, Auteur ; Isabelle Pochard, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Cement and concrete research (Vol. 39 N° 8, Août 2009) |
| Article en page(s) : | pp. 637–643 |
| Note générale : | Génie Civil |
| Langues : | Anglais |
| Tags : | 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 |
