Development and field applications of silica fume concrete in Canada: a retrospective

The effects of silica fume on the properties of plastic and hardened concrete are now fairly well-established. If properly used, silica fume imparts significant improvement to the strength and durability of concrete; and the availability of this material together with high-range water reducers (superplasticizers) has been largely responsible for the development of high-strength and high-performance concretes. Silica fume has been used in the Canadian cement and concrete industry for over 15 years. Early use was driven by economy, since concrete of a given strength grade could be produced at lower cementitious material content (and cost) if silica fume was incorporated in the mix due to the initial low selling price of the material. The construction boom of the mid to late 1980s saw the exploitation of high-strength silica fume concrete for high-rise construction. By the 1990s, concerns over the deteriorating infrastructure had shifted the focus to concrete durability and silica fume was finding applications in high-performance concrete. Today, silica fume is perhaps the material of choice for engineers designing concrete to withstand aggressive exposure conditions. This paper documents the major developments in the use of silica fume in Canada and discusses the wide range of applications for which the product may be used to beneficial effect.Key words: blended cement, Canada, concrete, high-performance, silica fume.