Title: Review of Ettringite-Monophase Relationships in Portland Cement Systems
Author(s): H. Y. Ghorab
Publication: Symposium Paper
Appears on pages(s): 65-80
Keywords: ettringite; hydration; stability; temperature
The stability domain of stoichiometrically prepared ettringite and monosulfate hydrate in water at 30 and 1OOoC also in the presence of lime, alite, monocarboaluminate hydrate, or each other is reported. The formation conditions of both calcium sulfoaluminate hydrates in pure ordinary portland cement dealing mainly with the hydration behavior of the tricalcium aluminate and the tetracalcium aluminoferrite in the presence of gypsum, also of lime, alite, or each other at 300C is summarised. The type of hydrate formed in sodium -hydroxide, sulfate solution or as a result of alkali doping in the structure of the anhydrous phase is given. The ettringite/monophase formation and duration in the three stages of C3 A and C4 AF hydration (instantaneous reaction, dormant, and acceleration period) are described. The present review focused on the stability of the calcium sulfoaluminate hydrates is a summary of 13 publications.