Title: Use of stabilizer/VMA to adjustment of the flow properties of SCC at the Job Site

Author(s): L. N. Thrane, C. Pade, M. Kaasgaard

Publication: NCR

Volume: 40

Issue: 1

Appears on pages(s): 1-10

Keywords: Concrete, 4C-Rheometer, SCC, Stabilizer, VMA

DOI:

Date: 12/15/2009

Abstract:
Successful use of SCC typically places greater demand on logistics of concrete delivery and on control of flow properties at the jobsite than is the case with conventional slump concrete. One poor truck load of SCC or minor stops in concrete delivery can ruin an SCC casting. Consequently, it is crucial to have means of remedy if concrete is delivered at a jobsite with unacceptable flow properties. One option, if the concrete is segregating at delivery, could be to correct the flow properties at the jobsite by adding stabilizer/VMA before the concrete is poured into the formwork. This approach, although not presently supported by the European concrete standard EN 206-1, has been investigated for typical Danish strength class C30 and C25 concrete using two commercially available stabilizers. The results indicate that the controlled addition of stabilizer/VMA at the jobsite can be a superior solution to rejecting the concrete or simply ignoring the deficient flow properties and casting the concrete anyway.