Effects on hydration products

DTA (K32,025) and XRD (A29) studies indicate that cement pastes cured at temperatures of or approaching lOO C contain little or no detectable hydrated aluminate phases, the observation of hydrogarnet noted above thus being unusual. Kalousek and Adams (K32) considered that the Al , 864 and other ions were incorporated into a Phase X , which possibly included all the oxide components of the cement. In pastes cured normally, much of the AFm phase is probably poorly crystalline and intimately mixed with the C-S-H (Seetion 7.3.1). This tendency may be increased if hydration takes place more rapidly. 

Studies on calcium silicate pastes show that the distribution of silicate anion size is shifted significantly upwards with a rise in curing temperature (Section 5.3.2). XRD gives no definite indication that the C-S-H formed at temperatures up to 100 C is more crystalline than that formed at ordinary temperatures, though the product of the 2-month treatment at 90 C mentioned earlier (T5) contained a little a-CjSH, a crystalline phase which is 

Calcium aluminate cements behave well at low temperatures (Section 

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