As #TyphoonBavi lashed Shanghai with powerful winds, the 1,000-tonne tuned mass damper (TMD), a device mounted in structures to reduce mechanical vibrations, inside the 632-meter Shanghai Tower swung into action. The damper moved by as much as two meters, absorbing the building's sway.Designed to withstand strong winds and earthquakes, the TMD offers a fascinating glimpse into the engineering systems that protect one of the world's tallest buildings. #ChinaTech