Page 67 - Handbook of Thermal Analysis of Construction Materials
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Section 5.0 - Hydration of Portland Cement 49
composition of C-S-H (in terms of C/S ratio) is variable depending on the
time of hydration. At 1 day, the C/S ratio is about 2.0 and 1.4–1.6 after
3+
3+
several years. The C-S-H can take up substantial amounts of Al , Fe , and
2-
SO ions.
4
Figure 5. Fraction of cement phases hydrated in cement pastes at different times.
Recent investigations have shown that in both C S and portland
3
cement pastes, the monomer that is present in the C S and C S compounds
3 2
4-
(SiO tetrahedra) polymerizes to form dimers, and larger silicate ions as
4
hydration progresses. The gas liquid chromatographic analysis of the
trimethyl silylation derivatives has shown that anions with 3 or 4 Si atoms
