Comment by EGreg

Comment by EGreg a day ago

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This. It is like roots of a tree for instance. The trunk by itself is actually much smaller than the branches — like the opposite of a pyramid.

I guess most of the stress is distributed throughout the building frame going into the foundation - like they drive those pylons into the ground before building a large building.

But still, it could snap from all that stress, like a tree that’s been felled by the wind…

That is why the other part is that skyscrapers are designed to sway in the wind and have the entire structure above the ground absorb the kinetic energy and sorta cancel it out before it reaches the base.

Some buildings use tuned mass dampers (like the giant pendulum in Taipei 101) to counteract swaying by moving in opposition to the wind-induced motion.

In fact, a lot of the time the majority of the building’s outer shell (glass etc) can be blown out by the wind, if it is too strong, and the steel structure will then have a lot of holes in it for the wind to pass through.

They test these structures for how the wind and water will flow around them. Look at the base of the Burj Al Arab, and how they built it to withstand the 100-year storm.

https://theskydeck.com/do-skyscrapers-sway/