Download - High performance concrete
Mehta and Aitcinsuggested the term high performance concrete (HPC) for concrete mixtures that possess the following three properties: high-workability, high-strength, and high durability.
American Concrete Institute defines High Performance Concrete as
“A concrete which meets special performance and uniformity requirements that cannot be achieved by routine conventional concrete.”
Compressive Strength(N/mm2) High Performance Concrete Class
50 I
75 II
100 III
125 IV
150 V
Cement
Fine Aggregate
Coarse Aggregate
Water
Mineral Admixtures such as
Fly ash
Silica fume
Ground granulated blast furnace slag
Chemical Admixtures such as Superplasticizers
Cement containing as little C3A as possible
Cement should be finely ground and contain fair amount of C3S
Sand or crushed stones may be used.
Having minimum void ratio.
Strength of HPC is controlled by strength of coarse aggregate.
Hence selection of coarse
aggregate would be an
important step in
HPC design mix.
Requirement of water should be reduced to the required quantity.
Increase in the speed of construction.
High workability and pump ability.
Improved Durability in aggressive and marine environment.
Service life more than 100 years.
Higher initial cost and reduced maintenance cost.
Low shrinkage and high strength.
Manufactured and placed much more carefully.
Extended Quality Control is required.
Very Early Strength (14 MPa in 6 hours),
High Early Strength (34 MPa in 24 hours),
Very High Strength (69 MPa in 28 days),
High Early Strength with Fiber-reinforcement.
HPC is being extensively used now for the
fabrication of precast pylons, piers, and girders of
many long span bridges in the world: