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DOE OSTI · 23206363

Long-term cement hydration studies with isothermal calorimetry

Wadsö, L.·Jansen, D.
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Abstract

The purpose of this study was to investigate for how long the thermal power of hydration can be measured with isothermal calorimetry, which is a general measurement technique with stable properties that, in many cases, can detect low rates of processes. Measurements were conducted for 365 days on cement paste with Portland cement, fly ash blended Portland cement and different water-to-binder ratios. The results showed that all the tested systems still produced a measureable signal after one year. The samples with Portland cement were also analyzed by XRD after 365 days, and phase composition calculations were made with GEMS. Together with the calorimetric results, these results were used to determine the degree of hydration by five methods, the results of which showed good agreement.

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36 MATERIALS SCIENCECALORIMETRYFLY ASHHYDRATIONPORTLAND CEMENTSIGNALSX-RAY DIFFRACTION

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Wadsö, L., Jansen, D.. 2021-03-15. Long-term cement hydration studies with isothermal calorimetry. https://doi.org/10.1016/j.cemconres.2020.106344

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36 MATERIALS SCIENCE↗