Progress in cement science - why alkaline activation?

Abstract

Fifty years ago just an idea of the presence of free alkalis in a cement matrix was considered by the ordinary portland cement (OPC) people as an absurd one and this was a basic postulate accepted in the chemistry of cements. In 1957 a scientist from Ukraine (USSR) Victor Glukhovsky put forward an assumption which was taken as a base for development and bringing into practice of construction a principally new class of cementitious materials which first appeared in the art under a name of “alkaline cements” (now also known under a general name of “alkali-activated cements (AAC)”. A validity of these ideas is confirmed by more than 50 years of evolutional development and vast experience collected from practical use of new materials in a variety of large-scale applications. A present review covers theoretical views on role played by alkali in cement stone structure formation. Examples of compositional build-up of the alkali- activated cementitious materials as a function of quantity of alkali and type of aluminosilicate component are reported as well as the results of inspection taken over the AAC concrete structures made with these cements.