Drying Shrinkage of SCC – Influence of the Composition of Ternary Composite Cements

Abstract

There is an increasing interest of developing and using composite cements, e.g. to reduce CO2-emmissions in cement production. This paper discusses results from an investigation of the influence of composition of ternary composite cements on the drying shrinkage of a typical low cost SCC for buildings (w/cm = 0.55) as used in Norway. Various Portland cements (CEM I), Portland fly ash cements (CEM II/A-V), Portland limestone cements (CEM II/A-L) and a Portland-composite cement (CEM II/B-M) were tested. The fineness of clinker phase, fly ash and limestone were varied systematically in the cements. Shrinkage was determined from length measurements of 500 mm long prisms, 100 x 100 mm in cross section, stored in water from demoulding until 7 days of age and then at 50% RH until 12 months of age. As expected, increased fineness and early reactivity of the cements increased shrinkage. The results showed, however, that the drying shrinkage was not significantly affected by the cement type. I.e. replacing up to 35% of the clinker by fly ash and limestone did not influence the drying shrinkage.