Created with Sketch.

1. Nov 2019 | Application Areas

Hydration of Portland cement

A new study deals with the hydration of ternary Portland cement mixtures containing metakaolin and sodium bentonite.

A trowel with grey paste lies on the edge of a bucket.

The results indicate that the coexistence of sodium-bentonite and metakaolin enhances the cement hydration. Source: Voyagerix –

Although metakaolin can enhance the hydration of cement, its pozzolanic reactions occur primarily at the early age with a high heat-release rate and low degree of reaction resulting in a reduction in the composite strength especially at high substitution levels. To address this challenge, a combination of metakaolin and sodium-bentonite is adopted as a partial replacement of cement. The influence of coupled substitutions of these two clays on hydration of Portland cement is investigated by characterising hydration kinetics and products related to microstructural and physico-chemical parameters.

Enhancement of cement hydration

The results indicate that the coexistence of sodium-bentonite and metakaolin enhances the cement hydration in terms of strength development, portlandite consumption and formation of supplementary calcium silicate hydrate (C-S-H) phases with elongated molecular chain lengths. Dissolution of metakaolin is increased in the presence of bentonite. It was found that the conversion of ettringite to monosulfate, the formation of strätlingite, and the length of aluminosilicate chains increase with increasing Al/Si ratio, which is related to the amount of dissolved metakaolin. A thermodynamic simulation is also presented to support these findings.

The study is published in: Cement and Concrete Research Volume 123, September 2019, 105772.

EC Library Formulating Adhesives and Sealants


Formulating Adhesives and Sealants

This book teaches adhesive and sealant formulation in two steps. Each section first describes the application and chemical basis of the type of adhesive or sealant concerned. This is followed by formulation advice and - if possible - an analysis of existing recipes. This analysis includes a calculation of the important characteristic values of the formulations. All calculations based on recipes and formulations are worked through step by step and should therefore be intelligible to beginners, too.


This could also be interesting for you!


You are currently not logged in

To leave a comment, please log in.

For continuously improving and optimizing our websites, we use cookies. By using our website, you agree to the usage of cookies. For more information, please visit our Privacy policy.