The Effect of Alkaline Activator on Workability and Compressive Strength of Alkali-Activated Slag Concrete

Behfarnia, K.; Taghvayi Yazeli, H.; Khalili Khasraghi, M. B.

doi:10.22060/ceej.2017.12375.5190

The Effect of Alkaline Activator on Workability and Compressive Strength of Alkali-Activated Slag Concrete

Document Type : Research Article

Authors

Department of Civil Engineering, Isfahan University of Technology, Isfahan, Iran

10.22060/ceej.2017.12375.5190

Abstract

In this study, experimental results on alkali activated slag (AAS) concrete was assessed to achieve the optimum strength and workability. The alkali contents of Na2O to activate slag in concrete were equal to 3.5, 4.5, 5.5, 6.5 and 7.5 % by mass of slag and silicate moduli of alkali solution varied from 0.45, 0.65, 0.85 and 1.05. The compressive strength test of concrete specimens over 7, 28 and 90 days was measured. To evaluate the concrete workability, the slump of fresh concrete and the setting time of paste were also examined. The results showed that in the proposed range of activation, by increasing the amount of alkali concentration as well as silicate modulus in activator solutions, the workability and compressive strength increased but the setting time of paste reduced. Optimum values for the preparation of AAS mixtures with suitable compressive strength and desirable workability are suggested based on the results.

Highlights

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Keywords

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