Preprint Article Version 2 Preserved in Portico This version is not peer-reviewed

Mechanisms of Phase Transformation and Creating Mechanical Strength in a Sustainable Calcium Carbonate Cement

Version 1 : Received: 22 October 2018 / Approved: 23 October 2018 / Online: 23 October 2018 (08:10:14 CEST)
Version 2 : Received: 6 May 2020 / Approved: 6 May 2020 / Online: 6 May 2020 (14:50:13 CEST)

How to cite: Rodríguez-Sánchez, J.; Liberto, T.; Barentin, C.; Dysthe, D.K. Mechanisms of Phase Transformation and Creating Mechanical Strength in a Sustainable Calcium Carbonate Cement. Preprints 2018, 2018100526 (doi: 10.20944/preprints201810.0526.v2). Rodríguez-Sánchez, J.; Liberto, T.; Barentin, C.; Dysthe, D.K. Mechanisms of Phase Transformation and Creating Mechanical Strength in a Sustainable Calcium Carbonate Cement. Preprints 2018, 2018100526 (doi: 10.20944/preprints201810.0526.v2).

Abstract

Calcium carbonate cements have been synthesized by mixing amorphous calcium carbonate and vaterite powders with water to form a cement paste and study how mechanical strength is created during the setting reaction. In-situ XRD was used to monitor the transformation of ACC and vaterite phases into calcite and a rotational rheometer was used to monitor the strength evolution. There are two characteristic time scales of the strengthening of the cement paste. The short timescale of the order 1 hour is controlled by smoothening of the vaterite grains, allowing closer and therefore adhesive contacts between the grains. The long timescale of the order 10-50 hours is controlled by the phase transformation of vaterite into calcite. This transformation is, unlike in previous studies using stirred reactors, found to be mainly controlled by diffusion in the liquid phase. The evolution of shear strength with solid volume fraction is best explained by a fractal model of the paste structure.

Subject Areas

calcium carbonate cement; setting reaction; (re)crystallization kinetics; cement strengthening; crystal bridging

Comments (1)

Comment 1
Received: 6 May 2020
Commenter: Jesus Rodriguez Sanchez
Commenter's Conflict of Interests: Author
Comment: The new version includes an updated analysis of the phase transformations during the cement setting and a couple of extra sections explaining the fast increase of elastic modulus and the structure of the pastes.
+ Respond to this comment

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 1
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.