Effect of Curing Condition and Carbonation on Hydration of Blast Furnace Slag Cement
By Takahiro Sagawa and Toyoharu Nawa
Concrete Research and Technology
Vol.18, No.3, Sep. 2007 (Issue 45)
- Synopsis:
- Ordinary Portland cement and blast furnace slag cement pastes with various water to binder ratio between 30 to 50% were hydrated under different curing conditions. Hydration ratio of cement compounds and slag, amount of hydration products were determined quantitatively by Rietveld method. Hydration of BFS is a little delayed in air-dried curing of 60%RH. CaO/SiO2 molar ratio of C-S-H decrease as increasing the amount of produced Ca(OH)2; CaO/SiO2 molar ratio of C-S-H in blast furnace slag cement is about 1.6, ordinary Portland cement is about 1.8 at the age of 91 days in water curing. CaO/SiO2 molar ratio of C-S-H in blast furnace slag cement and ordinary Portland cement remarkably decrease below 1.0 from carbonation.
- Keywords:
- Blast furnace slag, Cement compound, Rietveld method, Hydration ratio, Hydration products, Curing condition, Carbonation