Title:
Effect of Fly Ash Composition on Sulfate Resistance of Cement
Author(s):
P. K. Mehta
Publication:
Journal Proceedings
Volume:
83
Issue:
6
Appears on pages(s):
994-1000
Keywords:
blended cements; calcium; cement pastes; ettringite; fly ash; sulfate resistance; x-ray diffraction.
DOI:
10.14359/1892
Date:
11/1/1986
Abstract:
A laboratory investigation involving 16 fly ash samples of varying calcium content was undertaken with the objective of further clarifying the relationship between fly ash composition and sulfate resistance. A Type I portland cement was used to prepare blended cements containing 25 or 40 percent fly ash by weight. The resistance to sulfate attack was evaluated by immersion of well-cured neat cement paste specimens in a standard sulfate solution for a given period and by determining the strength loss as a result of sulfate exposure. The results show that rather than the chemical composition or the R-factor of a fly ash, it is the mineralogical composition of the cement-fly ash interaction product that controls the sulfate resistance.