Deformation properties of blended cement concretes containing blastfurnace slag and condensed silica fume

Blended cement concretes incorporating blastfurnace slag and condensed silica fume (CSF) were tested for elastic modulus, creep and shrinkage strains, with a view to comparing their performance with that of plain Portland cement concretes. Exposed and sealed specimens were investigated. The results showed that the exposure condition of the specimens during testing was critical. The addition of slag had the effect of causing a possible small increase in creep and shrinkage at early ages in exposed specimens, but this effect was usually reversed at later ages. Strains were markedly reduced in sealed slag specimens. The addition of CSF effected further moderate reductions in strains. Within-source and between-source variability of Portland cement clinkers with regard to movement properties appeared to be considerable. The use of a blended cement resulted in less variability in cumulative strains.