Ceramics-Silikáty 49, (4) 237 - 241 (2005)

This paper presents experimental study to determine the effect of temperature on the hydration kinetics of metakaolin (MK)–lime sludge–silica fume mixture. The kaolin was activated at 800°C for 2 hours. The metakaolin and lime sludge were mixed in a ratio of 1:1. To this mixture, 5 wt.% of silica fume was added to form the final blended composition. The water/binder ratio is 0.93 by weight. The specimens were cured at temperature 20 and 60°C at 100% relative humidity (RH). The phase composition of the formed hydrates was determined by X-ray diffraction and from the thermal analysis (TG and DSC) data. The results showed that the compressive strength of sample cured at 60°C was greater than that cured at 20°C. It is also demonstrated that, the sequence of appearance of hydrated phases at 20°C was CSH, C₂ASH₈ and C₄AH₁₃; while the formed hydrates at 60°C were CSH, C₂ASH₈, C₄AH₁₃ and hydrogarnet (C₃ASH₆).