Tae Bo Workout Sent Skyscraper Shaking

MiniMike writes "According to CNN: 'Seventeen people performing a vigorous Tae Bo workout caused tremors that forced the evacuation of a South Korean skyscraper earlier this month, the building's owners say. Scientists recreated the event in the 12th floor gym, according to a report in the Korea Times.' I don't know which is scarier, that they made such a flimsy skyscraper, or the sight of 17 scientists doing a Tae Bo workout. Hopefully they're better at it than the scientists I've seen in the gym."

Comments

Re:It's that bridge all over again

[TheRaven64]

Which bridge? The Tacoma Narrows Bridge, that shook itself apart, is one famous example, but it's not the only one. The Millennium Bridge in London had a similar problem. If people walked across it at a normal walking pace, their footsteps were at the bridge's resonant frequency. Worse, when a bridge starts to resonate like that, people naturally start walking in sync with the vibrations, making it worse. It cost £5m to fix - over 25% of the original construction cost.

Not even remotely related

[SuperBanana]

The article concerns a workout which happened to hit the resonant frequency of the structure, which was properly designed. The failure you linked to had to do with criminal negligence by the owners ignoring repeated engineering and construction firms who refused to accept design changes driven by greed (and were fired for it), completely repurposed building usage leading to gross overloading of the structure's strength, and then completely incompetent handling of obvious signs of structural failure (failure to immediately evacuate the building.) For fuck's sakes, they removed columns for escalators, then cut into the remaining columns, then ADDED A STORY WITH POURED CONCRETE FLOORS *and* an air conditioning unit the building wasn't designed for. And then when the building started to fail, they just blocked off areas to hide it from customers because they didn't want to lose sales revenue.

Re:resonance

[DeathElk]

They're obviously having too much fun blowing shit up to worry about responding to your points.