(U.S. Concrete) Building Blocks is a weekly column in the New York Times on what New York City looks like, and how it got that way.
At 3 World Trade Center, blue nylon mesh framed the work platforms around and below the 54th floor, the highest point in the building last February, when I visited. (It is now taller than 4 World Trade Center.)
Three hundred and twenty cubic yards of concrete were being poured, pumped up from trucks arriving steadily from the Ferrara Brothers plant in the Red Hook section of Brooklyn, while steel was being erected below.
What makes this construction project unique is that the concrete core of the skyscraper is rising before the steel columns and beams are erected around the perimeter, giving the current facade of the building a unique look to say the least. This construction technique is almost never used for New York office towers, making the $2.75 billion building project a sight to behold.
The concrete core of the skyscraper, according to the article, is is help stabalize the building against lateral movements, especially wind. These buildings with concrete cores, constructed in this manner, can be found across the world in the most famous metropolises: Seoul, Dubai, Beijing, London and more. But ironworkers were traditionally skeptical of the technique because they feared a health risk being below the process of concrete installation.
9/11 changed the way construction unions approached construction techniques, however. The planes that struck the original World Trade Center towers ran straight through the steel cores of those skyscrapers. This inspired the revisiting of composites and techniques that had previously lacked consideration.
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