Characteristics of Silica‐Fume Concrete
Publication: Journal of Materials in Civil Engineering
Volume 6, Issue 3
Abstract
Proper introduction of silica fume in concrete improves both the mechanical and durability characteristics of the concrete. This paper presents the results of research effort conducted at the American University in Cairo using Egyptian silica fume in concrete. The program investigated various characteristics of silica‐fume concrete. It emphasized the effect of silica fume on workability level and its maintenance of fresh concrete; strength development, strength optimization and elastic modulus of hardened concrete; and chemical and mechanical durability of mortar. The experimental program comprised six levels of silica‐fume contents (as partial replacement of cement by weight) at 0% (control mix), 5%, 10%, 15%, 20%, and 25%, with and without superplasticizer. It also included two mixes with 15% silica fume added to cement in normal concrete. Durability of silica‐fume mortar was tested in chemical environments of sulfate compounds, ammonium nitrate, calcium chloride, and various kinds of acids. It was found that there was an optimal value of silica‐fume content at which concrete strength improved significantly. Due to the slow development of pozzolanic effect, there was a drop in early strength up to seven days and late significant gains up to 56 days upon introducing silica fume to concrete. Elastic modulus, toughness, and steel‐concrete bond increased at the optimum silica‐fume content in concrete. Silica‐fume mortar exhibited significant improvement in durability against chemical attacks of most salts and acids. The improvement was moderate in the case of sulfate compounds. Mechanical erosion resistance increased moderately in silica‐fume concrete.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
ACI Committee 226. (1987). “Silica fume in concrete.” ACI Mat. J., 84(2), 158–166.
2.
Berra, M., Ferrara, G., and Tavano, S. (1989). “Behavior of high erosion resistant silica‐fume mortars for repair of hydraulic structures.” Publ. SP‐114, Vol. II, American Concrete Institute, Detroit, Mich., 827–848.
3.
Burge, T. (1983). “14,000 psi in 24 hr.” Concrete Int.: Des. and Constr., 5(9), 36–44.
4.
Carette, G., and Malhotra, V. M. (1983). “Early age strength development of concrete incorporating fly ash and condensed silica fume.” Publ. SP‐79, II, American Concrete Institute, Detroit, Mich., 765–784.
5.
Cohen, M., and Bentur, A. (1988). “Durability of portland cement‐silica fume pastes in magnesium sulfate and sodium sulfate solutions.” ACI Mat. J., 85(3), 148–157.
6.
Detwiler, R., and Mehta, K. (1989). “Chemical and physical effects of silica fume on the mechanical behavior of concrete.” ACI Mat. J., 86(6), 609–614.
7.
Galeota, D., and Giammatteo, M. (1989). “Stress‐strain relations of normal and lightweight concrete with silica fume under uniaxial compression.” Publ. SP‐114, Vol. II, 991–1012.
8.
Gjorv, O., Monteiro, P., and Mehta, P. (1990). “Effect of condensed silica fume on the steel‐concrete Bond.” ACI Mat. J., 87(6), 573–580.
9.
Lea, F. M. (1970). The chemistry of cement and concrete. Edward Arnold Publishers, Ltd., London, U.K.
10.
Maage, M. (1986). “Strength and heat development in concrete: influence of fly ash and condensed silica fume.” Publ. SP‐91, Vol. II, American Concrete Institute, Detroit, Mich., 923–940.
11.
Sandvik, M., and Gjorv, O. (1986). “Effect of condensed silica fume on the strength development of concrete.” Publ. SP‐91, Vol. II, American Concrete Institute, Detroit, Mich., 893–902.
12.
Sellevold, E. J., and Radjy, F. F. (1983). “Condensed silica fume (microsilica) in concrete: water demand and strength development.” Publ. SP‐79, Vol. II, American Concrete Institute, Detroit, Mich., 677–694.
13.
Yamato, T., Soeda, M., and Emoto, Y. (1989). “Chemical resistance of concrete containing condensed silica fume.” Publ. SP‐114, Vol. II, American Concrete Institute, Detroit, Mich., 897–914.
Information & Authors
Information
Published In
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Jul 8, 1993
Published online: Aug 1, 1994
Published in print: Aug 1994
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.