Application of H-1 NMR to hydration and porosity studies of lime-pozzolan mixtures

作者：Tziotziou M; Karakosta E; Karatasios I; Diamantopoulos G; Sapalidis A; Fardis M; Maravelaki Kalaitzaki P; Papavassiliou G; Kilikoglou V^*

来源：Microporous and Mesoporous Materials, 2011, 139(1-3): 16-24.

DOI：10.1016/j.micromeso.2010.10.010

• NMR relaxometry
• Mercury porosimetry
• Nitrogen adsorption
• Porosity
• Mortar hydration

H-1 nuclear magnetic resonance (NMR) relaxation is applied to lime-pozzolan mixtures to monitor in real-time the hydration and porosity evolution during setting. The hydrated products formed during the setting of these mixtures are similar to those formed in hydraulic binders (e.g. cement and natural hydraulic limes). In this work, we demonstrate that by using a portable, low field (0.29 T) Halbach magnet it is possible to study in detail, the evolution of the pore structure, modified through the formation of C-S-H and C-A-H, by means of the H-1 NMR technique. Contrary to the standard porosimetry methods, which require drying procedures before analysis. NMR is a non-invasive straightforward technique, allowing the study of the hydration kinetics in real-time, during the setting and hardening of the lime-pozzolan binding system. Thus, by measuring the H-1 NMR spin-lattice relaxation T-1 of two lime-pozzolan mixtures, it was possible to distinguish between different pore populations within the system (at different setting periods), and to study the growth of the hydrated phases. The interpretation of the results proved that, similarly to mercury intrusion porosimetry (MIP) and nitrogen adsorption, H-1 NMR probes the development of the pore structure within the lime-pozzolanmortar matrix, indicating key changes of pore size populations.

• 出版日期2011-3