Scanning electron microscopic investigations of fresh mortars: Well-defined water-filled layers adjacent to sand grains
- Norcem AS, Heidelberg Cement Group, N-3991Brevik (Norway)
SEM examinations are reported of freshly-mixed and early age mortar specimens prepared by fast freezing in liquid nitrogen followed by epoxy impregnation, and of companion specimens of early aged mortars prepared conventionally. Freshly-mixed mortars reveal complex features that appear to influence subsequent development of the hardened state microstructure. In particular, layers of entirely water-filled space a few micrometers thick are found adjacent to many of the sand grain surfaces. After a few hours sparse deposits of calcium hydroxide crystals (and later C-S-H) are found within these layers, but the layers persist as recognizable features for at least 12 h. The layers are identically recognizable in both fast-frozen and conventionally-prepared specimens. Another feature found in freshly-mixed mortars is the existence of patchy local areas of sparsely-packed and other areas of densely-packed cement particles.
- OSTI ID:
- 21033078
- Journal Information:
- Cement and Concrete Research, Vol. 38, Issue 4; Other Information: DOI: 10.1016/j.cemconres.2007.11.006; PII: S0008-8846(07)00289-X; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0008-8846
- Country of Publication:
- United States
- Language:
- English
Similar Records
Microstructural Features of a Mortar as Seen by Computed Microtomography
Use of polypropylene fibers coated with nano-silica particles into a cementitious mortar