Activation of fly ash and its effects on composite cement properties

摘要

A new method of fly ash (FA) activation with addition of Ca(OH)_2 and small quantity of Na_2SiO_3 is put forward in this paper. SEM, DTA, XRD analyses, alkali-absorption test and strength measurement indicate that the activity of FA activated by this method is obviously increased. Activated fly ash (AFA) can accelerate cement early hydration, promote setting and hardening and be an excellent accelerator for setting and hardening.