SCANNING ELECTRON MICROSCOPE CHARACTERIZATION OF THE SURFACES OF ASTM C109 STANDARD OTTAWA SAND GRAINS

Surface microstructural features of Ottawa sand prescribed for mortar strength tests of portland cements in ASTM C 109 have been examined by scanning electron microscopy. The observed features include large areas of rounded grain surface that appear etched or frosted at low magnification and are seen to consist of sharp hills and valleys on a scale of a few micrometres; some areas of smooth planar surfaces representing cleavage planes; a number of large dish-shaped concavities thought to arise through conchoidal fractures associated with violent grain-to-grain contact; and incised lines separating some of the frosted surface into roughly polygonal blocks about 50 microns across. The frosted areas probably represent the results of repeated local dissolution and reprecipitation of silica. (Author)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/3528769
• Corporate Authors:

  American Society for Testing and Materials (ASTM)

  100 Barr Harbor Drive, P.O. Box C700
  West Conshohocken, PA  United States  19428-2957
• Authors:
  • Barnes, B D
  • Diamond, S
  • Dolch, W L
• Publication Date: 1979

Media Info

• Features: Figures; References;
• Pagination: p. 21-24
• Serial:
  • Cement, Concrete and Aggregates
  • Volume: 1
  • Issue Number: 1
  • Publisher: American Society for Testing and Materials (ASTM)
  • ISSN: 0149-6123
  • Serial URL: http://journalsip.astm.org/JOURNALS/CEMENT/cca_home.html

Subject/Index Terms

• TRT Terms: Electron microscopes; Microstructure; Portland cement; Sand; Silica; Texture
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00314667
• Record Type: Publication
• Files: TRIS
• Created Date: Feb 18 1981 12:00AM