Title: Resistance of Alkali-Activated Slag Mortars to Chloride Solution

Author(s): J. Deja and J. Malolepszy

Publication: Symposium Paper

Volume: 114

Issue:

Appears on pages(s): 1547-1564

Keywords: activators; alkalies; blast furnace slag; binders (materials); chemical attack; chlorides; compressive strength; copper;

DOI: 10.14359/1886

Date: 5/1/1989

Abstract:
The chemical resistance of alkali-activated slag pastes and mortars in chloride solutions was studied. The four basic slag-alkali binding materials were prepared using granulated blast furnace slag, copper slag, and a mix of both these components. NaOH and Na?2CO?3 were used as activators. Some pastes and mortars containing 10 percent active silica additive were also made. The mortars were cured in standard conditions as well as subjected to low-pressure steam curing. The chemical resistance of alkali-activated slag mortars was compared with the chemical resistance of OPC mortars. The water-to-solid ratio was kept constant at 0.40. The samples cured in water were considered as reference samples. It has been found that the alkali-activated slag binders are chemical resistant in chloride solutions. These results were found not only from chemical resistance in chloride solutions and compressive and flexural strength tests, but also from the SEM observations of microstructure. The difference between the chemical resistance of slag and OPC mortars is probably the consequence of phase composition and porosity of the hydration products