Journal Published Online: 01 July 1984
Volume 6, Issue 1

The Variability of Condensed Silica Fume from a Canadian Source and Its Influence on the Properties of Portland Cement Concrete



Condensed silica fume is formed during the manufacture of ferrosilicon in electric submerged-arc furnaces. The use of condensed silica fume has been evaluated in portland cement concrete. Thirty-two samples of condensed silica fume, each collected on consecutive days, were analyzed for chemical and physical routine quality control tests of pozzolan. Eight of these samples, representing the variations of the routine tests, were tested for complete ASTM Specification for Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete (C 618) conformance. All of the samples tested were found to conform to ASTM C 618 with the exception that the water requirement was excessive.

Concrete mixtures were evaluated with a fixed quantity of 24 kg/m3 (40 lb/yd3) of condensed silica fume. The low portland cement content mixtures show slightly higher shrinkage after 64 weeks of drying; the rich mixtures have the same shrinkage. Compressive strengths were more than 30% higher than control mixtures having low cement contents and were more than 10% higher than control mixtures having higher cement contents. This amount of condensed silica fume was found to have no effect on the time of set relative to control mixtures containing the same portland cement content.

Author Information

Pistilli, MF
American Admixtures and Chemicals Corporation, Chicago, IL
Rau, G
SKW Canada, Inc., Parc Industriel Du Centre Du Québec, Becancour, Quebec
Cechner, R
American Admixtures and Chemicals Corporation, Chicago, IL
Pages: 5
Price: $25.00
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Stock #: CCA10351J
ISSN: 0149-6123
DOI: 10.1520/CCA10351J