June 27, 2008: Very Big Ball

[xoxoxoBruce]

A very big ball, I mean a 728 ton, very big ball.
From deputy dog;

The enormous steel ball you see in the photos is the world’s largest ‘tuned mass damper’ and sits near the top of the world’s largest completed skyscraper on earth, taipei 101 in taiwan. The idea behind a tuned mass damper is quite simple: as a building sways (resulting from high winds, earthquakes etc), its tuned mass damper, essentially a finely tuned and ridiculously heavy pendulum, will move in opposition to the structure’s oscillations and minimise any movement.

Due to both the immense size of taipei 101 and the fact that it sits just over 600ft from a major fault line, engineers had no choice but to install one of this size at a cost of $4m. Too heavy to be lifted by crane, the damper was assembled on site and hangs through 4 floors of the skyscraper. it can reduce the building’s movement by up to 40%.

Here's the ball in action, during the May 12th quake, that shook China so badly.

[newtimer]

Talktalktalktalktalktalktalktalktalk... (we're on the 89th floor of a building that is built just 600' from a fault line).. talktalktalktalktalktalktalk.. (there's a gigantic ball that will sway if there's an earthquake).. talktalktalktalktalktalk.. (and it just now started swinging back and forth. A lot.).. talktalktalktalktalktalk.. (what should I do? Think I'll chat in my cell phone for a few minutes and watch the big earthquake ball swing some more.).. talktalktalktalktalk... (and listen to the other tourists keep jabbering away.)

[xoxoxoBruce]

Well, they don't worry about no stinkin' quake... they got big ball(s).

[SPUCK]

That would be a bit of a bummer if those cables broke... I wonder how long it would take it to get to the basement...

[glatt]

Awesome find, Bruce!

This is really interesting.

[Sundae]

If I was there with someone else I'd be talktalktalk too.
Are we in the safest place?
Hang on, does this mean there is an earthquake going on, I can't feel it?
Should we head off or do you think this is a test [yes, stupid response, but I might], the building doesn't appear to be shaking?

If I was on my mobile I would carry on talking:
Mum, are you okay? I'm in this weird place and there's a huge ball that's just started moving! It can't mean what I think it does!

My assumption is that if there were any normal indications of an earthquke these people would have exhibited all the screaming and running you hoped to see.
The fact that they didn't, and only the ball responded, meant that it was reacting to tremors that could have damaged the building, but weren't destroying anything at that point.

I might be wrong, no idea where Teipei lies in regards to the epicentre.
But it seems unlikely that even "tourists" would stand and talk if they felt the building shake on its foundations.

[HungLikeJesus]

If I had the office directly below that ball, I'd always be thinking, "There's a one-and-a-half million pound steel ball hanging above my head, supported by cables made of green Chinese steel."

[Griff]

Wow spectacular! Is it possible that a really long duration quake would allow the ball to catch up....?

[YellowBolt]

Originally Posted by Sundae Girl

I might be wrong, no idea where Teipei lies in regards to the epicentre.
But it seems unlikely that even "tourists" would stand and talk if they felt the building shake on its foundations.

It's... like 900 miles away. About the distance from California to Missouri.

I saw the ball a few years ago when I went to Taiwan. It was... bally.

[Karenv]

This is experimental technology. They have no business erecting their phallic symbols full of human beings just 600 feet from a fault line. What part of "Don't build big buildings next to fault lines" don't they understand?

I do not understand this mania for the world's biggest buildings going up all over. Give me something where I can see the ground and open the windows, and get out in case of emergency.

[Sarasvati48]

Then they all went downstairs to the street and realized a horrific earthquake had taken place...

[newtimer]

Originally Posted by YellowBolt

It's... like 900 miles away.

Correct. Chengdu to Taipei is a little more than 1,100 miles. That's about the distance from Dallas, straight north, to the Canadian border.

[Flint]

I'm out of time here. I need somebody to write a clever reply, having something to do with Quasimodo. kthxbai

[DanaC]

If I had the office directly below that ball, I'd always be thinking, "There's a one-and-a-half million pound steel ball hanging above my head, supported by cables made of green Chinese steel."

Oh yeah...that thought would definately be a recurring one

[BigV]

Why make it in the shape of a sphere?

A sphere is the shape that has the highest volume to surface area ratio, but I don't see any compelling reason to have to conserve surface area for this counterweight. It seems like it would be a wasteful use of space compared to, say, a cylinder, perhaps a cylinder with a hemispherical lower end. Since the whole weight will swing in an arc described by the radius of the cable and ball, it would seem that there would be empty space in the swing path that could otherwise have been used to add mass, had they departed from their (nearly) spherical choice.

Perhaps there were aesthetic reasons for the shape I don't understand.