Scanning Electron Microscopic Investigations of Fresh Mortars: Well-defined Water-filled Layers Adjacent to Sand Grains

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.

• Record URL:
  https://doi.org/10.1016/j.cemconres.2007.11.006
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00088846
• Supplemental Notes:
  • Abstract reprinted with permission from Elsevier
• Authors:
  • Diamond, S
  • Kjellsen, K O
• Publication Date: 2008-4

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 530-537
• Serial:
  • Cement and Concrete Research
  • Volume: 38
  • Issue Number: 4
  • Publisher: Elsevier
  • ISSN: 0008-8846
  • Serial URL: http://www.sciencedirect.com/science/journal/00088846

Subject/Index Terms

• TRT Terms: Calcium silicate; Cement mortars; Fresh concrete; Hydration; Microstructure
• Uncontrolled Terms: Scanning electron microscopy
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01099382
• Record Type: Publication
• Files: TRIS
• Created Date: May 21 2008 7:06AM