High Performance Concrete

HPC concretes are usually designed using materials other than cement alone to achieve these requirements, such as flyash (from the coal burning process), ground blast furnace slag (from the steel making process, or microsilica fume (from the reduction of high quality quartz in an electric arc furnace). Different amounts of these materials are combined with Portland Cement in varying percentages depending on the specific HPC requirements.

Though there are many definitions for High Performance Concrete (HPC), the most widely-accepted one is that given by the American Concrete Institute, which states; “High Performance Concrete is concrete that meets special performance and uniformity requirements that cannot always be achieved routinely by using only conventional materials and normal mixing, placing and curing practices.” It is not possible to give a unique definition of HPC without determining the performance requirements of the intended use of the concrete.

With the development of HPC, emphasis has in many cases – such as that designed for bridge and roadway construction - shifted from compressive strength to other properties of the materials, such as high density, low permeability and resistance to some forms of environmental attack. Though High Performance Concrete is often of high strength, not all high strength concrete is High Performance.

The Federal Highway Administration has adopted criteria for this type of concrete:

Freeze-Thaw Durability – the resistance of concrete to repeated cycles of freezing and thawing during cold weather

Scaling Resistance – measures the amount of resistance to surface scaling in the presence of de-icing chemicals

Abrasion Resistance – measures the amount of wear that will result from constant traffic loads

Chloride Penetration – determination of depth to which concrete salts and de-icing agents will penetrate the concrete

Elasticity – measure of the simple tension stress, which will be applied to concrete in use

Shrinkage – determines the length change in hardened concrete due to causes other than externally applied forces or weather

Creep – measures the tendency of concrete to slowly deform or move permanently under certain stresses

Compressive Strength – amount of load that concrete will bear (measured in pounds per square inch)

Ralph Clayton & Sons was the first company in New Jersey to supply a Department of Transportation project with High Performance Concrete for the Route 9 Bridge over the Raritan River. Other projects supplied by Ralph Clayton & Sons include:

Route 35 Victory Bridge connecting Sayreville to Perth Amboy, NJ

Routes 1 & 130 Intersection in North Brunswick, NJ

Route 70 9/11 Memorial Bridge over the Manasquan River Brick Township to Brielle - the 2008 American Concrete Institute Grand Award winner

Route 52 Causeway spanning from Somers Point to Ocean City, NJ

Route 36 Highland Bridge Replacement at Sandy Hook, NJ

Routes 1 & 9 St. Paul’s Avenue Bridge project in Jersey City, NJ