Water content modifies the structural development of sodium metasilicate-activated slag binders

The effect of modifying the water content of an alkali - activated slag binder was assessed, in terms of the kinetics of reaction and the structural development of the material. There is not a s ystematic correlation between the water content of the mix and the rate of reaction, indicating that there is an optimal value that favours dissolution of the slag and precipitation of reaction products. A h igher water content reduce d the crystallinity and density of the reaction products, especially at advanced age. Small changes in the water content can have a significant impact on the compressive strength development of alkali - silicate activated slag mortars, suggesting that when producing materials base d on alkali - activated binders , it is essential to carefully control the water content.

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