ABSTRACT
Although fly ash and slag are popular choices as raw materials for producing alkali-activated materials, they have marked structural, chemical and physical differences. In general, the alkali activation of slag will result in the dissolution of calcium and participation of Al to form a C-A-S-H type gel. Therefore, partial slag substitution in alkali-activated fly ash will produce a binder system consisting of both N-A-S-H and C-A-S-H gels. With increasing amount of slag, the dissolved calcium concentration will increase and lead to the formation of more CSH products. When slag was used as the sole raw material in production of the binder, CSH gel was found to dominate the reaction products.
