Influence of modification of SiO2 on the formation of calcium silicate hydrate

• Autorzy: Baltakys K. , Jauberthie R. , Siauciunas R. , Kaminskas R.
• Języki publikacji: EN

Abstrakty

EN

Interactions of Ca(OH)2 with various modifications of SiO2: amorphous (Hi-Sil, TSD) or crystalline (quartz) silica were established. The molar ratio of primary mixtures CaO/SiO2 was 0.5. The samples were cured in a vapour chamber (20 oC, 100% humidity) for 7 and 28 days. The products were characterized by X-ray diffraction, thermogravimetry, differential scanning calorimetry, Fourier-transform infrared and scanning electron microscopy analysis. SiO2 modification used had a decisive influence on the processes of formation of calcium silicate hydrates. In the mixture with amorphous SiO2, Ca(OH)2 reacted completely during 7 days of synthesis, while large quantity of Ca(OH)2 remained unreacted even after 28 days when quartz was used. It was found that in the Ca(OH)2-amorphous SiO2-H2O system, after a 28-day exposure, the surface of SiO2 globules was totally covered with well-crystalline C-S-H(I) plates. Moreover, in the samples with quartz, only the gaps between quartz crystals were filled with C-S-H(I).

Słowa kluczowe

EN

calcium silicate hydrate; crystalline SiO2; silica fume; Portland cement; X-ray diffraction

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2007
• Tom: Vol. 25, No. 3
• Strony: 663--670
• Opis fizyczny: Bibliogr. 16 poz.

Twórcy

autor

Baltakys K.

autor

Jauberthie R.

autor

Siauciunas R.

autor

Kaminskas R.

• Department of Silicate Technology, Kaunas University of Technology, Radvilenu 19, LT - 50270 Kaunas, Lithuania

Bibliografia

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