Effectiveness of common water-reducing admixtures in alkali-activated slag pastes with different types of activator

نویسندگان

چکیده

Abstract Rheology of alkali-activated slag (AAS) is a very complex issue, where the activator nature as well its dose play an important role. Moreover, use water-reducing admixtures in these systems they often do not work properly. This could be attributed to high pH surface chemistry AAS. Therefore, lignosulfonate-, polynaphthalene- and polycarboxylate-based superplasticizers were used modify AAS pastes with sodium waterglass, hydroxide carbonate activator. These tested using rotational rheometer oscillatory shear mode increasing strain observe evolution viscoelastic moduli determine stress corresponding linear region limit (“yield point”) crossover point, storage modulus equals loss (“flow point”). In most cases, plasticizers did improve rheological properties; only exception was lignosulfonate one hydroxide-activated slag.

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ژورنال

عنوان ژورنال: IOP conference series

سال: 2021

ISSN: ['1757-899X', '1757-8981']

DOI: https://doi.org/10.1088/1757-899x/1205/1/012001