1513Types of HPC

Fiber-reinforced concrete (FRC) — Concrete with sufficient fiber reinforcement to provide ductility or toughness equal to at least five times the area under the stress-strain curve for the same concrete mixture without fiber reinforcement. FRC is normally associated with toughness, that is, the ability to absorb energy. This energy absorption occurs primarily after the ultimate strength of the concrete has been attained.

High-durability concrete — Concrete with a minimum durability factor (freezing and thawing) of 80%, as measured by AASHTO T 161 (Method A) (or ASTM C 666), and a w/c ratio of 0.35 or less. A maximum w/c of 0.35 will provide a paste with a discontinuous capillary system after a relatively short curing period (normally about a day). This provides improved resistance to moisture penetration and chemical attack from the environment.

High-strength lightweight concrete — concrete produced by using lightweight aggregates, such as expanded clay, shale, and slate aggregates, so as to reduce the mass from 20 to 25% below that of conventional concrete. Some lightweight concrete can attain compressive strengths greater than 69 MPa (10,000 psi). This type of HPC is desirable in applications where reduction of dead load is a significant consideration.

Self-consolidation concrete — It is also called self-compaction concrete. In fresh stage, such a concrete has the ability to fill formwork and encapsulate reinforcing bars only through the action of gravity, and with maintained homogeneity.

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