DIFFERENTIAL THERMAL ANALYSIS TESTS OF HYDRATED CEMENTS AND INDIVIDUAL HYDRATES

Samples were examined in five laboratories using four different makes of equipment. Variations were observed among different analyzers. The results obtained on a given instrument were reproducible and generally suitable, within capabilities of the instrument, for at least partial analyses of the cement paste for hydrous phases. Trends of phase changes, as related to the time of curing, were the same for all laboratories. These phase changes related to the kind of cement and the water content of the paste. High instrument sensitivity (chart deflection per unit temperature difference between sample and reference) was required for optimum results. The phases in a hydrating cement at room temperature, detected by DTA, are gypsum, calcium sulfate hemihydrate, ettringite, tetracalcium aluminate monosulfate-12-hydrate, tetracalcium aluminate hydrate, tricalcium aluminate-6-hydrate (and other hydrogarnets), calcium hydroxide, magnesium hydroxide, and substituted calcium silicate hydrate gel (C-S-H gel). The carboaluminates, in the presence of some of the above phases, are not distinctly detectable. /Author/

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 30-41
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00141050
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Oct 6 1976 12:00AM