Title: Impact of Different Type of Calcium Sulfate on Early Ettringite Formation in Presence of Different PCE

Author(s): Lukas Frunz, Patrick Juilland, Emmanuel Gallucci, and Jorg Zimmermann

Publication: Symposium Paper

Volume: 329

Issue:

Appears on pages(s): 155-164

Keywords: concrete; PCE; cement; calcium sulfate; ettringite; sulfatation

DOI: 10.14359/51711211

Date: 9/26/2018

Abstract:
In this article, we investigate the effect of small differences in type, amount or blend of sulfate carrier on the formation of early ettringite, especially in presence of PCE polymers. We used a commercial cement clinker before addition of the sulfate carrier and added different types, amounts or blends of calcium sulfate. The resulting blends were hydrated without PCE and including three different PCE. We followed the evolution of the amount, the specific surface area and the total ettringite surface per mass of paste over time. We observed very different evolution of the respective parameters depending on the type/blend of sulfate carrier used. Furthermore, presence of PCE had additional individually different impacts on these parameters, depending on the structure of the PCE. These impacts are mainly attributed to interactions of the PCE with ettringite precursors leading to stabilization of such precursors in presence of PCE.