Title: The Influence of Viscosity-Modifying Admixture (VMA) on the Performance of Self-Consolidating Concrete (SCC)

Author(s): B.J. Christensen and F.S. Ong

Publication: Symposium Paper

Volume: 233

Issue:

Appears on pages(s): 9-24

Keywords: air-entraining admixture (AEA); bleeding; compressivestrength; high-range water reducer (HRWR); segregation index; self-consolidating concrete (SCC); time of setting; viscosity-modifyingadmixture (VMA); visual stability index

DOI: 10.14359/15820

Date: 3/9/2006

Abstract:
The stability of highly fluid self-consolidating concrete (SCC)can be achieved by using a viscosity-modifying admixture (VMA).Currently, there are several types of VMAs available in the market place.Three of the most common ones are based on cellulose-ethers, biopolymers and synthetic polymers. The properties of these three typesof VMAs were studied and compared. Specifically, the influence of thesethree types of VMAs on the properties of self-consolidating concrete (SCCwas studied. Particular attention was placed on the influence of eachVMA on the following characteristics of the SCC: 1) dose response of high range water reducer (HRWR), 2) dose response of air entrainingagent (AEA), 3) stability of the mixture, 4) effects on time of setting and 5compressive strength development.