The American Concrete Institute (ACI) defines high-performance concrete as concrete meeting special combinations of performance and uniformity requirements that cannot always be achieved routinely when using conventional constituents and normal mixing, placing and curing practices.
The High performance concrete usually contains both pozzolanic and chemical admixtures. Hence, the rate of hydration of cement and the rate of strength development in HPC is quite different from that of conventional cement concrete (CCC). This HPC can be used where both strength and durability are important considerations and to produce a more economical product, provide a feasible technical solution, or a combination of both.
A high-performance concrete is one in which certain characteristics are developed for a particular application and environment. Examples of characteristics that may be considered critical for an application are:
* Ease of placement
* Compaction without segregation
* Early age strength
* Long-term mechanical properties
* Permeability
* Density
* Heat of hydration
* Toughness
* Volume stability
* Long life in severe environments
The most commonly used supplementing cementitious materials/mineral admixtures
for achieving HPC are :
1. Silica Fume
2. Fly Ash
3. Ground granulated blast furnace slag (GGBFS )
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