Early-age creep and shrinkage of blended cement concrete

Abstract

This paper reports a study on the early-age creep and shrinkage of concrete with and without silica fume (SF), ground granulated blast-furnace slag (GGBS), and their combinations. The test parameters were water-binder ratio, aggregate content, partial replacement of cement by SF, GGBS, or both, as well as test conditions (drying versus sealed conditions). The stress-strength ratios at loading were fixed at 30% of the 3-day compressive strength and 20% of the 3-day tensile strength for compressive and tensile creep, respectively. The test environment was controlled at a temperature of 30 ± 2 C and a relative humidity (RH) of 65 ± 5%. The compressive and tensile creep together with drying and autogenous shrinkage were determined over 4 months of loading. The results obtained for plain, double-blended, and triple-blended concrete were assessed and compared to provide guidelines on the use of SF and GGBS in concrete structures subjected to early-age creep and shrinkage.