Title:
Early Reactivity Assessment of Calcined Clays and the Impact of Secondary Phases
Author(s):
Tafadzwa Ronald Muzenda, Fabien Georget, Thomas Matschei
Publication:
Symposium Paper
Volume:
362
Issue:
Appears on pages(s):
720-732
Keywords:
pozzolanic reactivity; calcined clays; early-age reactivity; compressive strength
DOI:
10.14359/51742004
Date:
6/17/2024
Abstract:
In this study, we use different natural clays with a variety of mineral and chemical compositions to seek to understand the influence of the secondary minerals (i.e. not kaolinite) on early-age performance. The study shows that the R3 test is not suitable to assess the early-age reactivity, and early-age properties (compressive strength, rheology). It is also shown that the early-age performance of calcined clays is not dominated by metakaolin content and that secondary phases or impurities – for example, iron phases have a significant impact. A clinker-free model system with the aim of studying early-age reactivity is introduced.
Related References:
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