Materiales de Construcción, Vol 62, No 306 (2012)

Mechanical behaviour of alkali-activated blast furnace slag-activated metakaolin blended pastes. Statistical study

I. Higuera
Universidad Politécnica de Madrid, Spain

C. Varga
Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc- CSIC), Spain

J. G. Palomo
Universidad Politécnica de Madrid, Spain

A. Gil-Maroto
Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc- CSIC), Spain

T. Vázquez
Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc- CSIC), Spain

F. Puertas
Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc- CSIC), Spain


The study and development of alternative, more ecoefficient binders than portland cement are attracting a good deal of scientific and technological interest. Binders obtained from the chemical interaction between calcium silico-aluminous materials and highly alkaline solutions are one of several types of such possible cements. The present paper discusses the mechanical behaviour and mineralogical composition of blended pastes made from NaOH-activated vitreous blast furnace slag and metakaolin. The aim of the study was to determine how parameters such as the slag/metakaolin ratio, activating solution concentration and curing temperature affect strength development in these binders. A statistical study was conducted to establish the impact of each variable and model strength behaviour in these alkaline cements. The conclusion drawn is that activator concentration and the slag/metakaolin ratio are both determinant parameters.


alkaline cements; blast furnace slag; mechanical strength; experimental design; ANOVA

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