Why Taipei 101 hangs a 660-tonne ball in its upper floors: the tuned mass damper
30seconds
At the top of Taipei 101 a 660-tonne steel ball hangs in plain view. It is not decoration: it is a tuned mass damper that swings against the building and can cut its sway by up to 40%.
Play with two identical towers in the same gusty wind, one with a hanging ball and one without. Drag the tuning away from perfect and watch the benefit vanish, then sweep the wind to see one tall resonance split into two low ones.
Deep dive · 4 min
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