Title: Effect of Blended Cements on Effectiveness of Internal Curing of HPC

Author(s): D. Cusson

Publication: Symposium Paper

Volume: 256

Issue:

Appears on pages(s): 105-120

Keywords: autogenous shrinkage; cement type; early-age cracking; high-performance concrete; internal curing; lightweight aggregate; paired comparison design; restrained movement; stress development

DOI: 10.14359/20235

Date: 10/1/2008

Abstract:
The effects of internal curing, type of blended cement and coarse aggregate size on earlyage expansion, autogenous shrinkage, and strength of high-performance concrete were investigated. To do so, 12 high-performance concrete mixtures were developed and tested under sealed and room temperature conditions. The results were statistically analyzed using the paired comparison design method. It was shown that internal curing of HPC with presaturated porous lightweight aggregate allowed signifi cant autogenous expansion and resulted in considerable reduction in net autogenous shrinkage. The type of cement used in concrete, which was either ordinary portland cement, silica fume blended cement, or slag/silica fume blended cement, had a strong effect on early-age expansion, autogenous shrinkage, and the effectiveness of internal curing. For instance, the concrete specimens made with silica fume blended cement, which yielded the largest autogenous shrinkage strains under sealed conditions, obtained the best reductions in autogenous shrinkage when tested under an internal curing condition.