topicmaker Veteran
  
  
  Joined: 28 Feb 2006 Posts: 25847
 
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				 Posted: Fri Aug 14, 2015 1:43 pm    Post subject: This 720-Ton Suspended Steel Ball | 
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				The heavy counterweight hangs between the 92nd and the 87th floor, acting as a tuned mass damper, which keeps the building stable during high winds.
 
 
 
 
 
   
 
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