Chemical characterization of cement composites- A FTIR study
- Vol.96(2), Feb
- Thane ACC LTD 2022
- 35-40p.
Chemistry of cement hydration is studied by many methods including spectroscopic method. Fourier transform infrared spectroscopy (FTIR) method works on the principle of absorption of infrared light at different wavelengths which are characteristics of chemical composition. Nowadays, in order to reduce the cement consumption in concrete, supplementary cementitious materials (SCMs) such as fly ash, ground granulated blast furnace slag (GGBS) are used as cement replacement materials. When such SCMs are used, hydration mechanism is altered that in turn affects the strength of cement concrete. For any improved properties of cement concrete, mixes need to be engineered or modified and is possible only when the hydration mechanism is properly understood. In view of this, in the present work, the hydration of fly ash / GGBS cement composites and engineered composites have been investigated by using the FTIR analysis. Modification in the major hydrates such as Portlandite and C-S-H are investigated. During the ageing of the hydrated cement paste, particularly, when pozzolanic material like fly ash is used, the polymerization of silica and the decalcification happens that are identified by the shift in the position of the major bands of C-S-H by the FTIR.