Thermoporometry and Proton NMR Measurement on Cement Paste Equilibrated at Different Relative Humidities

Abstract

In this study, thermoporometry by differential scanning calorimetry and proton NMR measurements of hardened cement paste equilibrated under different humidity conditions were carried out, and the results of both measurements were compared. The results reveal that thermoporometry by low temperature DSC measurement cannot detect the water present in samples equilibrated at low relative humidity. On the other hand, it is possible to detect a signal at low relative humidity by proton NMR measurement. It is clarified that water strongly bound to the surface, which cannot be detected by low temperature DSC, exists at a relative humidity of 33% or less. If it is relevant to detect tightly held water, such as water present in the fine gel pores, it is recommended to apply proton NMR measurements. This paper is an extended English version of the authors' previous work [Kurumisawa, K. and Jensen, O. M., (2020). "Measurement of cement paste at different humidities by thermoporometry and proton NMR."

Distribution and Dynamics of Water in the Blended Pastes Unraveled by Thermoporometry and Dielectric Properties

“…Bager and Sellevold [40] reported that no ice was formed in hardened cement paste equilibrated at RH of 33 % and 11 %. No exothermic peak was detected in white cement paste at 33 % RH [41] as well. Fig.…”

Effect of alkali activators on diffusivity of metakaolin-based geopolymers

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