(MIStructE_IRE) That building is certainly a masterpiece koot. Wow! I’m assuming that the catenary (which looks like large steel sections) wouldn’t require any degree of post tensioning and is simply hanging there supporting all those floors? I wonder what the vibrations are like?
Without running any numbers, I'd guess the structure is very resistant to vibrations. A walker on one floor must excite much of the building to get floors moving, so the effective mass would be enormous.
So the architect on the Federal Reserve Building was one of my favorites--Gunnar Birkerts (he also designed the Corning Museum of Glass--take a look at that sometime). Birkerts was a guest professor at the University of Illinois my junior year (Spring 1983), so I heard him speak a few times. I don't remember him speaking about the Federal Reserve Building, but years later someone told me he supposedly designed the building to have an open plaza for those working in or visiting downtown Minneapolis. Thus the catenary, and no columns below. I also read that Birkerts was giving a nod to the Gateway Arch in St. Louis, designed by his mentor, Eero Saarinen. However, the same person who told me he "supposedly" designed it with a plaza below told me he designed the building years earlier with no particular location in mind--he was an architect with a building looking for the right client!
