Title:
Behavior of Activated Ternary Binders under Autogenous Condition
Author(s):
Aveline Darquennes and Farid Benboudjema
Publication:
Symposium Paper
Volume:
326
Issue:
Appears on pages(s):
22.1-22.10
Keywords:
alkali-activated binders, blast-furnace slag, cracking sensitivity, fly ash, shrinkage, sodium carbonate, sodium sulphate
DOI:
10.14359/51711004
Date:
8/10/2018
Abstract:
In order to reduce the carbon footprint of the Portland cement manufacture, clinker is often substituted by mineral additions. Binders with a high content of mineral additions limit the greenhouse gas emissions and have interesting sustainability properties: low permeability, better resistance to leaching, etc. However, these materials are characterized by slow hydration kinetics. To accelerate their hydration kinetics and to improve their strength at early age, various solutions exist: additional grinding, thermal curing and use of chemical activators for example. In this article, the effects of chemical activation on the performance of blended binders are experimentally studied under autogenous condition. Two types of activators are tested in different contents: sodium sulphate and carbonate. Based on the mechanical properties and autogenous shrinkage, a performance index is proposed to determine the cracking sensitivity of these mixtures.
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