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Effect of Na₃PO₄ on the Hydration Process of Alkali-Activated Blast Furnace Slag.

ABSTRACT: In recent years, the utilization of different non-traditional cements and composites has been increasing. Alkali-activated cementitious materials, especially those based on the alkali activation of blast furnace slag, have considerable potential for utilization in the building industry. However, alkali-slag cements exhibit very rapid setting times, which are too short in some circumstances, and these materials cannot be used for some applications. Therefore, it is necessary to find a suitable retarding admixture. It was shown that the sodium phosphate additive has a strong effect on the heat evolution during alkali activation and effectively retards the hydration reaction of alkali-activated blast furnace slag. The aim of the work is the suggestion of a reaction mechanism of retardation mainly based on Raman and X‑ray photoelectron spectroscopy.

SUBMITTER: Kalina L

PROVIDER: S-EPMC5503029 | biostudies-other | 2016 May

REPOSITORIES: biostudies-other

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