Hydration, Structure, and Properties of Blast Furnace Slag
Cements, Mortars, and Concrete
D. M. Roy and G. M. ldorn
Appears on pages(s):
alkalies; blast furnace slag; calcium hydroxides; durability; granular materials; heat of hydration; hydration; porosity; slag cements.
The hydration characteristics of blends of ordinary portland cement and blast furnace slag (in the range of 50 percent slag content are discussed, both regarding the early stages of hydration where considerable temperature rise occurs, corresponding to the curing phase for concrete, and concerning supplementary long-term hydration; as during the performance stage for concrete. The kinetics of the hydration process are described and special phenomena of hydration of the slag fraction in the blends are traced to the glassy structure of slag, in contrast to the behavior of the predominantly crystalline portland cement phases. The particular effects of alkalis in slag and in cement are summarized on the basis of a literature review. Activation by alkalis and thermal activation may be synergistic. Beneficial effects of cements with blast furnace slag on the chemical resistance of concrete are outlined with reference to a forthcoming paper on this subject.