Mystery #3Tier 2forces and materials

Why is it safer for a skyscraper to sway in the wind than to stand rock-solid?

At the top of a tall skyscraper on a windy day, you can sometimes feel the whole building gently swaying, like the deck of a ship. It sounds alarming, but engineers planned it that way on purpose. A tower with no give at all would have to be brittle, and brittle things crack. Why is it safer for a skyscraper to sway in the wind than to stand rock-solid?

The Shard rising in a tapering glass spike above the London skyline, a tower tall and slender enough to lean a little at the top in a gale — Photo: Diego Delso · CC BY-SA 4.0 · via Wikimedia Commons

Your guess

What do you think would happen to a completely stiff tower when the wind shoves against it?

There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.

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