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PREFACE:

The first use of alkali as a component of cementing material dates back to 1930, when Kuhl investigated the setting behaviour of mixtures of ground slag powder and caustic potash solution. Chassevent measured reactivity of slags using caustic potash and soda solution in 1937.

 Purdon (1940) did the first extensive laboratory study on clinkerless cements consisting of slag and caustic soda or slag and caustic alkalis produced by a base and an alkaline salt in 1940. The important historic developments of alkaliactivated cements are summarized in Table 1.1. In later 1957, Glukhovsky first discovered the possibility of producing binders using low basic calcium or calcium-free aluminosilicate (clays) and solutions of alkali metal (Glukhovsky 1959). 

He called the binders “soil cements” and the corresponding concretes “soil silicates”. Depending on the composition of starting materials, the binders can be divided into two groups: alkaline binding system Me2 O–Me2O3–SiO2–H2 O and alkalineearth alkali binding system Me 2 O–MeO–Me2O3–SiO2–H2 O.

 Extensive researches and developments on alkali-activated cements and concrete have been carried out since then. The Trief cements and F-cements from the Scandinavian countries (Forss 1983a, b) and alkali-activated blended cements are more recent examples (Davidovits 1988, Roy and Silsbee 1992). In 1981, Davidovits of France produced binders by mixing alkalis with burnt mixture of kaolinite, limestone and dolomite (Davidovits 1981). He called the binders “geopolymer” since they have polymeric structure. 

He also used several trademarks such as Pyrament, Geopolycem and Geopolymite for the binder (Davidovits 1994). This type of materials virtually belongs to the alkaline binding system Me 2 O–Me2O3–SiO2–H2 O, as discovered by Glukhovsky. Maleket al.(1986) identified alkali-activated cement type materials as the matrix formed in the solidification of certain radioactive wastes, while Roy and Langton (1989) showed some analogies of such materials with ancient concretes.