This paper deals with the strength development, pore structure develop
ment, rapid chloride permeability and water permeability of alkali-act
ivated slag mortars activated by 6% (by mass of Na2O) NaOH, Na2CO3 and
Na2SiO3. The Na2SiO3-activated slag mortars exhibited the highest str
ength at both early and later ages, even much higher than a typical co
mmercial Type III portland cement. NaOH-activated slag mortars exhibit
ed the lowest strength. The pore structure measurements were consisten
t with strength results. Four common strength-porosity equations: Bals
hin's, Ryshkevitch's, Schiller's, and Hasselmann's equations, fit the
experimental results from alkali-activated slag mortars with sufficien
t efficiency; of which Hasselmann's equation fit best. The charge pass
ed through the mortar specimens in the rapid chloride ion permeability
test appeared to be dependent more on the chemistry of pore solution
than on the pore structure of the mortars. Limited results from water
permeability testing appeared to be consistent with strength and pore
structure measurements. Copyright (C) 1996 Elsevier Science Ltd