[article]
Titre : |
The role of alkali content of Portland cement on the expansion of concrete prisms containing reactive aggregates and supplementary cementing materials |
Type de document : |
texte imprimé |
Auteurs : |
Medhat H. Shehata, Auteur ; Michael D.A. Thomas, Auteur |
Année de publication : |
2012 |
Article en page(s) : |
pp. 569–574 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Mots-clés : |
Alkali–aggregate reaction Alkalis Fly ash Pore solution Modified accelerated mortar bar test |
Résumé : |
This paper presents results covering the effects of alkali content of Portland cement (PC) on expansion of concrete containing reactive aggregates and supplementary cementing materials (SCM). The results showed that the alkali content of PC has a significant effect on expansion of concrete prisms with no SCM. When SCM is used, the expansion was found to be related to both the chemical composition of the SCM and, to a lesser extent, the alkali content of the PC. The concrete expansions were explained, at least partly, on the basis of the alkalinity of a pore solution extracted from hardened cement paste samples containing the same cementing blends. An empirical relation was developed correlating the chemical composition (Ca, Si and total Na2Oe) of the cementing blend (PC + SCM) and the alkalinity of the pore solution. Results from accelerated mortar bar test (ASTM C 1260) and a modified version thereof are also presented. |
En ligne : |
http://www.sciencedirect.com/science/article/pii/S0008884609002075 |
in Cement and concrete research > Vol. 40 N° 4 (Avril 2010) . - pp. 569–574
[article] The role of alkali content of Portland cement on the expansion of concrete prisms containing reactive aggregates and supplementary cementing materials [texte imprimé] / Medhat H. Shehata, Auteur ; Michael D.A. Thomas, Auteur . - 2012 . - pp. 569–574. Bibliogr. Langues : Anglais ( eng) in Cement and concrete research > Vol. 40 N° 4 (Avril 2010) . - pp. 569–574
Mots-clés : |
Alkali–aggregate reaction Alkalis Fly ash Pore solution Modified accelerated mortar bar test |
Résumé : |
This paper presents results covering the effects of alkali content of Portland cement (PC) on expansion of concrete containing reactive aggregates and supplementary cementing materials (SCM). The results showed that the alkali content of PC has a significant effect on expansion of concrete prisms with no SCM. When SCM is used, the expansion was found to be related to both the chemical composition of the SCM and, to a lesser extent, the alkali content of the PC. The concrete expansions were explained, at least partly, on the basis of the alkalinity of a pore solution extracted from hardened cement paste samples containing the same cementing blends. An empirical relation was developed correlating the chemical composition (Ca, Si and total Na2Oe) of the cementing blend (PC + SCM) and the alkalinity of the pore solution. Results from accelerated mortar bar test (ASTM C 1260) and a modified version thereof are also presented. |
En ligne : |
http://www.sciencedirect.com/science/article/pii/S0008884609002075 |
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