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Workability of Self-Compacting Concrete.


pdf icon Workability of Self-Compacting Concrete. (2554 K)
Ferraris, C. F.; Brower, L.; Ozyildirim, C.; Daczko, J.

High Performance Concrete International Symposium. Economical Solution for Durable Bridges and Transportation Structures. Proceedings. PCI/FHWA/FIB. September 25-27, 2000, Orlando, FL, 398-407 pp, 2000.

Keywords:

concretes; test methods

Abstract:

The slump test is widely used to evaluate the workability of Concrete. However it has serious drawbacks, especially for self-compacting concrete (SCC). Other flow characteristics such as viscosity or filling capacity or time of flow through an orifice are needed to characterize flow in SCC. The goals of this study were multiple: 1) to test flow characteristics of SCC using various devices: two concrete rheometrers, several standard tests, and the widely used V-flow and U-flow tests; 2) to determine the correlation between the two rheometers; and 3) to attempt to determine the rheological characteristics of SCC. Thirteen mixes were prepared with varying dosages of viscosity modifying admixture (VMA) and high-range water-reducing admixture (HRWR) to achieve a wide range of flow behavior. It was found that the plastic viscosities, measured with the two rheometers were correlated at 84% and that a SCC mixture is not defined by the high slump and slump spread alone.