On this project silica fume was added primarily to enhance constructability.
The exterior concrete walls in this structure are 4.5 ft (1.4 m) thick. To
prevent thermally induced cracking, the designer specified very tight
control over the maximum temperature rise allowed in the concrete. To meet
the requirements for concrete temperature, the contractor elected to use a
Class F fly ash in the concrete. While the fly ash did help to reduce
temperature development, the early strength gain characteristics of the
concrete were such that form removal was delayed. Addition of silica fume
to the concrete provided additional early strength to facilitate form
removal on a satisfactory schedule. For additional information, see:
Holland, T. C., "High-Performance Concrete: As High as It Gets!", The
Concrete Producer, V. 16, No. 7, July, 1998, pp. 501-505.
The Silica Fume Association
38860 Sierra Lane, Lovettsville, VA 20180
Tel: 540.257.4224 Fax: 540.822.9456
