I recently took a trip to St Louis where I had my second adventure to the Gateway Arch! The first time I went two years ago I was so excited I didn’t pay much attention to detail and design. This time I had the luxury of taking a friend who had never been before so I got to do a lot of the explain of how things worked AND we both paid a LOT of attention to how things were designed and how joints and ends came together.
After tightly packed tram ride to the top of the arch, we viewed out over the city taking it all in, trying to find our hotel and such. BUT we both felt like we could feel the arch moving the whole time! So one of the biggest questions we both had about the entire experience was: Does the arch really sway?! After some research I learned that the Arch does sway! Up to 9 inches in either direction in fact. Its designed to be resistant to wind up to 150MPH and earthquake resistant. This design feature is something that with the recent earthquake in Japan has become very important to a lot of people, having the security of knowing the building being designed will be able to survive and protect them during tragedy.
Another design feature that we both were in awe of and wanted to know more about was the exterior panels the arch is cladded with, and if the really narrowed as they went up or if it was just an illusion. Like with the swaying factor, I did some research when we got home about the structure of the building. The panels are 4x8 stainless steel, a skin covering that’s welded in place. The panels cover a carbon steal wall that’s reinforced with concrete in the middle, and this structure rises to 300ft, where it then turns in to solely the carbon steel all the way to the top. And as for the whether, the panels actually get smaller or not, the legs do actually narrow from 54ft to 17 ft. And the height and with of the structure are the same at 360ft!
A little extra trivia about the beautiful arch: there is a time capsule located welded into the keystone. The capsule holds signatures of 762,000 students from the St. Louis area, and the capsule was placed in right before the last piece was set in place. Very cool!
Do any of you have any interesting facts about the arch, or things that you have wondered about?