High-resolution solid-state nuclear magnetic resonance spectroscopy of portland cement-based systems

Abstract

Solid-state nuclear magnetic resonance (NMR) spectroscopy represents an important research tool for the characterisation and structural analysis of cement pastes and cement-based materials and has been increasingly employed in this field for more than the past 3 decades. A main advantage of the method is nuclear-spin selectivity, where one nuclear-spin isotope of the NMR periodic table (e.g. 1H, 11B, 19F, 27Al and 29Si) is detected at the time, which often results in rather simple but informative spectra for complex multiphase systems, such as cementitious materials. In addition, the resonances from these spin nuclei are most sensitive to local structural ordering and/or dynamic effects, which permits studies of not only crystalline phases but also amorphous components, such as the calcium-silicate-hydrate (C-S-H) phase, produced during the setting and hardening of portland cement. Thus, NMR complements a number of other analytical techniques which probe the long-range order of crystalline phases (e.g. X-ray diffraction [XRD]; cf. Chapter 4) or bulk chemical features.