Page 64 - Handbook of Thermal Analysis of Construction Materials

Section 4.0 - Behaviors of Individual Cement Minerals 47

was not based on adequate control of certain parameters such as particle size
distribution, water:solid ratio, specimen geometry, method of estimation of
the degree of hydration, etc. Beaudoin and Ramachandran [11] have re-
assessed the strength development in cement mineral pastes, both in terms
of time and degree of hydration. Figure 4 compares the results of Bogue and
Lerch with those of Beaudoin and Ramachandran. [11] Significant differ-
ences in the relative values of strengths developed by various phases were
found. At 10 days of hydration the strength values were ranked as
follows by Beaudoin and Ramachandran: C AF > C S > C S > C A. At
2
3
4
3
14 days, the relative values were in the order: C S > C AF > C S > C A.
3
3
2
4
The Bogue-Lerch strength values both at 10 and 14 days were: C S >
3
C S > C A > C AF. At one year, the corresponding values were: C S >
2 3 4 3
C S > C AF > C A (Beaudoin-Ramachandran) and C S > C S > C A >
3
2
3
2
4
3
C AF (Bogue-Lerch). Comparison of strengths as a function of the degree
4
of hydration revealed that at a hydration degree of 70–100%, the strength
was in the decreasing order: C S > C AF > C A.
3
4
3

Figure 4. Compressive strength of hydrated cement compounds. (Reprinted from Beaudoin,
J. J., and Ramachandran, V. S., Cement and Concrete Res., 22:689–694, 1992, with kind
permission from Elsevier Science Ltd, The Boulevard, Langford Lane, Kiddlington
OX51GB.)