Exercising Sways Skyscraper?

FISMA

I am not sure if I believe it, however, they are reporting that a group of seniors, exercising to the old song the Power by Snap, must have matched the natural frequency of their skyscraper and caused the upper floors to "tremor."

Possible? Yes and I am sure we've all heard of the break step bridge.
However, I don't think that's all to the story.

True, a little internal force, such as this, could, if timed correctly, bring the building down. However, the conditions would have to be so well timed and executed that I don't see it as being feasible.

Also, if this did happen as reported, I don't think the seniors would be able to work out "vigorously" for the length of time it would require to get this right.

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Scientist: Tae Bo workout sent skyscraper shaking

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.

Prime Group, owner of the 39-story TechnoMart commercial-residential high-rise in Seoul, said 17 middle-aged people were working out to the pop song "The Power" by Snap on July 5 when their movements set the upper floors of the tower shaking for 10 minutes, according to a report from the Korea JoongAng Daily.

Scientists recreated the event in the 12th floor gym, according to a report in the Korea Times.

“We observed the vibrometer while performing the same kind of aerobic exercise that was performed at the time of the shaking which occurred on July 5. We noticed that the shaking was felt in the upper floors while the exercise was being performed while no other place showed signs of tremor,” Chung Lan, a professor of architectural engineering at Dankook University, told the Korea Times.

“It just happens to be that the vibration cycle caused by Tae Bo collided with the vertical vibration cycle unique to the building,” Chung told the Korea Times. The action amplified the building's vibration and caused the shaking, he said.

Chung was one of six professors from the Architectural Institute of Korea who inspected the building and recreated the Tae Bo exercise.

Tae Bo is a mixture of boxing and tae kwon do.

krd

Skyscrapers, are actually supposed to do this thing where then there is a build up of energy in the structure, a part will vibrate and hum.

Possible? Yes and I am sure we've all heard of the break step bridge.
However, I don't think that's all to the story.

The "break step" is built into structures like bridges and buildings these days. Deliberate irregularities in the structures, so the structure does not have a single major resonant frequency.

I can't remember the name of the bridge (there is a documentary about it somewhere on line) - but an early suspension bridge in the US that collapsed after a storm - before it collapsed, it would do all kinds of weird wobbling, without much input. It was the regularity of the design - the bridge had harmonics, that once there was energy within these harmonics, it would bounce back and forth without being dissipated. So, when you build a bridge or skyscraper - you have to put in irregularities to dissipate energy that might enter the structure. A build with a regular structure will be like a tuning fork. What you'd like would be something like a wooden spoon.

FISMA

I think the name of the bridge was the Tacoma Narrows.

True, skyscrapers are designed for this. The Twin Towers swayed 6feet. Indeed there were times that doors on the top floors would not close due to the flex.

Timing such a resonant effect is difficult. In order to get results like Tesla's earthquake machine, I don't believe that people exercising is going to do it - just not as precise and application of Force.

krd

Something I read a few years back - I don't know if this is true.

It was in relation to particular Japanese skyscrapers.

Tension would build up in the structures - and then, occasionally, it would be released in the form of a vibration - which would be the resonant frequency of whatever particular cavity it was being released through. Parts of the building would literally hum.

fox65

Is there a way that this energy could be harnnessed?

The weight and forces involved is quiet large.

Surly a system of Larger linear electricity generators lining the exterior frame could generate useable electricity

Also this principle could be applied to bridges?

Is this possible? it is the same principle behind the mechanical powered flashlights. the ones you shake.

Turtwig

Believe it or not, Choreography is used to simulate earthquakes on various structures.:D

https://www.youtube.com/watch?v=BpCjGiQqjRM

Oh and the tacoma bridge is just an awesome example of resonance.:D

https://www.youtube.com/watch?v=3mclp9QmCGs