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New Video: Burj Khalifa - How To Build Higher
🕑 Added 2016-10-25 15:38:07 +0000 UTC The latest video is finally ready! A bit delayed due to problems with my old microphone, just invested in a new one using your pledges, so hopefully it shows in the audio quality.I also paid a small donation to the producer of the music in this video. His music is really cool and he allows people to use it for free. If you like his music check him out.
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Comments
Alex
Would the counterbalance also assist the skyscraper in resisting damage during g earthquakes? If so, could they build the Burj in a seismically active area?
Real Engineering
Ooooooooooh I didn't know that's how the Sears Tower worked. I'll be covering this concept properly at some stage. This is basically talking about the second moment of area. If you imagine a see-saw with weight in the middle, it's very easy to lift that weight, but the further you move it from the central axis the harder it is to lift. Bending metal works in a similar enough way. In bending there is an axis called the neutral axis, material along that axis does not resist bending and the further you get from it the more it resists the bending. The neutral axis of the building will be right in the middle, so by placing the metal on the outside of the building it increases the bending resistance of the building. That isn't a great explanation. I need time to word these things, but maybe it will give you an idea.
Matej 'Retro' Jan
This is great! Especially coming after I recently watched the NG documentary on the 10 innovations in skyscraper construction that lead to The Burj Khalifa. They talk about the swaying in this section: <a href="https://youtu.be/4mt8SifFqZQ?t=28m54s" rel="nofollow noopener" target="_blank">https://youtu.be/4mt8SifFqZQ?t=28m54s</a> What I didn't completely understand is the solution in the Sears Tower that starts here: <a href="https://youtu.be/4mt8SifFqZQ?t=29m36s" rel="nofollow noopener" target="_blank">https://youtu.be/4mt8SifFqZQ?t=29m36s</a> They didn't change the outside shape of the building at all, so how did the vortex patterns change/lessen? Or is it just that the forces are dissipated through the exoskeleton differently than a full grid frame, which makes it not sway as much? It's a great documentary, but I wished they could spend 15 minutes just explaining this part. :D That's why I also love your video, because it goes into details about these topics. I hope you can shed some light on the exoskeleton part as well.
