Mechanisms and Parameters Controlling the Tricalcium Aluminate Reactivity in the Presence of Gypsum

To understand the mechanisms and parameters controlling reactivity of tricalcium aluminate in the presence of gypsum at an early age, a study of the hydration of the "C-sub-3A–sulphate" system by isothermal microcalorimetry, conductimetry, and a monitoring of the ionic concentrations of diluted system suspensions were conducted with various gypsum quantities. The role of C-sub-3A source and its fineness were also studied. This work shows the fast initial formation of AFm phase followed by ettringite formation during the period when the sulphate is consumed. It is highlighted that the time necessary to consume all the gypsum varies with the type of C-sub-3A and has been attributed to the intrinsic reactivity of each one and mainly to the change of fineness from one C-sub-3A to another. Results are discussed alongside hypotheses from the literature to explain the slowing down of C-sub-3A hydration process in the presence of calcium sulphate.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00088846
• Supplemental Notes:
  • Abstract reprinted with permission from Elsevier
• Authors:
  • Minard, Helene
  • Garrault, Sandrine
  • Regnaud, Laure
  • Nonat, Andre
• Publication Date: 2007-10

Language

• English

Media Info

• Media Type: Print
• Features: Figures; Photos; References; Tables;
• Pagination: pp 1418-1426
• Serial:
  • Cement and Concrete Research
  • Volume: 37
  • Issue Number: 10
  • Publisher: Elsevier
  • ISSN: 0008-8846
  • Serial URL: http://www.sciencedirect.com/science/journal/00088846

Subject/Index Terms

• TRT Terms: Calcium sulfates; Chemical reactivity; Concrete; Ettringite; Gypsum; Hydration; Tricalcium aluminate
• Uncontrolled Terms: Early age
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01084676
• Record Type: Publication
• Files: TRIS
• Created Date: Jan 28 2008 8:11AM