Quadrozzi Concrete Corp. and iCrete are paving the way for the first office building to be built on "Ground Zero" in New York City. "The Freedom Tower will recapture the New York City skyline. . .establishing a new civic icon for our country," says World Trade Center Developer, Larry A. Silverstein, builder of the Freedom Tower. The building will contain 2.6 million square feet of office space, an observation deck, world-class restaurants, parking, and below-grade shopping and access to the PATH and subway trains.

14000 psi concrete is being used to build the core of the Freedom Tower, the first office building to be built on the former site of the World Trade Center. It is the first time such a high strength mix has been used in New York City.

To ensure quality and consistency, Quadrozzi installed process control systems in its two plants producing the special mixes. To-date, not a single load of the high strength concrete has been rejected from the job site.

The Freedom Tower's safety systems exceed New York City Building Code requirements. Architects Skidmore, Owings & Merrill designed the Tower with a redundant steel moment frame and concrete-core shear wall to resist lateral loads and provide column-free interior spans. All of the building's stairs, communications, risers, sprinklers and elevators are encased within the building's concrete core wall, which is up to six ft thick in some places. Concrete also protects all of the building's sprinklers and emergency risers.

Elements of the building pay tribute to the World Trade Center: the building's 200 sq. ft. footprint is the exact size of the World Trade Center towers, and a metal and glass parapet on the observation deck will mark 1362 ft. and 1368 ft., the two heights of the original towers.

This high-profile project represents an important milestone for high strength concrete. Engineers across the country are watching the progress of the project and learning new ways high strength concrete can shape their work in the future.

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