Hey, 14 online! Isn't that a new record?

[JKKJ]

Just noticed.

[Onomatopoeic]

Just noticed.

I doubt it. There's probably a zillion dweebs online at AOL right now.

[Handruin]

I posted the same thing the other day. :)

http://www.storageforum.net/phpBB2/viewtopic.php?t=638

[Handruin]

Except, I guess 14 is one more.

[Tannin]

If in doubt, ask James. He is good at counting, it seems. :)

[JKKJ]

James can you help? I'm sure that 14 is more than 13.

[James]

Grumbles: you make one little mistake in arithmetic, and you pay for it the rest of your life... :wink:

I expect Tony to step in here with a list of examples from history of those whose arithmetical errors have caused catastophes (Barings Bank, Enron, Global Crossing, etc. etc. don't count). :?:

[James]

I suppose the Titanic is a good one to start off with. Very strong != unsinkable.

The V... whatever it was Narrows Bridge in the US that has that famous piece of footage of it twisting itself to destruction.

I'm sure there are a fair few military examples too.

[Cliptin]

I suppose the Titanic is a good one to start off with. Very strong != unsinkable.

The V... whatever it was Narrows Bridge in the US that has that famous piece of footage of it twisting itself to destruction.

I'm sure there are a fair few military examples too.

Tacoma Narrows bridge. Talk about unforseen consequences. :o

[Platform]

...Then, it finally happened.

http://www.vislab.usyd.edu.au/photonics/fibres/fibre/images/tacoma.jpg
http://www.vislab.usyd.edu.au/photonics/fibres/fibre/movies/tacoma.mpg

[James]

That must have been amongst the most famous disaster footage (although I don't think m/any were killed?) until September 11 came along.

[Platform]

I'm pretty sure nobody got killed in this bridge incident. The automobile seen on the waffling bridge was abandonded.

I seem to recall seeing some other footage of some people walking off the bridge as fast as they could as they hung onto whatever they could in order not to be thrown or blown off the bridge as the situation became progressively worse.

[flagreen]

We lost about 25 people here in St. Petersburg the morning a phosphate freighter knocked down one span of the Sunshine Skyway Bridge during a driving rain storm. Most were in a bus that fell 500' to the bay.

[Prof.Wizard]

The Tacoma bridge incident was (and still is) a textbook-scenario for civil engineers. It happened because the brease down the river blowed in small shots of a frequency which matched te internal (inherent) frequency of oscillation of the bridge. This provoked augmenting oscillation of higher and higher width on every cycle (the waves were being summarized). From that day on, CEs have used construction materials and methods that don't allow the bridge (or any other construction) to "tune" to an outside enviroment frequency...

Sorry for my poor terminology or explaining, I'm no CE student. :(

[Corvair]

...It happened because the brease down the river blowed in small shots of a frequency which matched te internal (inherent) frequency of oscillation of the bridge...

Yes, it's fundamental sympathetic frequency -- due its length, shape, etc.

Many professions that build things nowadays are more attuned (pun intended) to sympathetic oscillations, including the designers of the International Space Station zooming around overhead as we speak. The Int'l Space Station has to correct regularly for oscillations that slowly build due to the ultra-low-frequency gravitational waves from the Earth by occasionally firing certain small stabilisers situated around the spacecraft for extremely brief periods. The original Int'l Space Station design from the late 1980s -- a triangular design that was unfortunately scrapped -- had a very clever oscillation dampening system, where it stabilised itself by simply pumping a dense fluid through plumbing around the perimeter in one direction or the other.

[Corvair]

We lost about 25 people here in St. Petersburg the morning a phosphate freighter knocked down one span of the Sunshine Skyway Bridge during a driving rain storm. Most were in a bus that fell 500' to the bay.

Ya, I recall that from the early '90s. Then there was a fog incident about 3 or 4 years ago where some people went over the railing at the top of the bridge.

[James]

Halifax in Canada where I lived for 6 years was the site of the largest man-made explosion (http://www.archives.ca/05/0518/05180202/0518020203_e.html) until the atomic bomb came along. December 6, 1917, during the first world war, a loaded ammunition ship collided with another ship and blew up - about 2,000 people died and up to 9,000 were injured in the explosion and the snowstorm that followed the next morning. 325 acres (about 2 sq. km) of Halifax were levelled by the force of the blast.

The explosion was so strong that windows were broken in Truro, almost 80km away, and the shockwave was felt in Sydney, Cape Breton, which is about 250km away. In Halifax itself you can go and see a window in the church downtown where the outline of a priest was essentially photographed into the glass by the flash of the explosion; there's a monument (http://www.region.halifax.ns.ca/community/publicart/montb.html) to the victims about 4km away from the site of the explosion, where the over half ton ship's anchor shank landed. One of its cannons went almost 7km in the opposite direction. Oppenheimer studied the effects of the blast in calculating the explosive power of the weapons that were eventually dropped on Hiroshima and Nagasaki.

Even bureaucratic letters (http://www.archives.ca/05/0518/05180202/051802020304_e.html) sent after the event are quite something to read.

As thanks to the people of Boston, who immediately sent a train full of supplies and help once they heard of the disaster, Halifax sends them a huge Christmas tree every year.

[Corvair]

...Most were in a bus that fell 500' to the bay.

BTW, I believe the Tampa Bay bridge is more like 200 feet above the water -- I've been over it several times, including back in the bad old days when it was 2 lanes.

There is a bridge near here called the Hartman Bridge (I believe that's its name). The roadway is 200 feet high at its highest point, though the massive yellow suspension towers above the bridge are WAY higher than the roadway at something around 500 feet high. There's no legs to hit out where the ships go through.

[Corvair]

Halifax in Canada where I lived for 6 years was the site of the largest man-made explosion until the atomic bomb came along...

There was something a bit like that happened here in this area, down the coast, in the early 1950s. It killed somewhere between 500 and 1000 people when it was all said and done. It was not a simple explosion, instead a series of explosions that killed nearby watchers and residents of Texas City up to a couple of miles away from the huge shockwaves, fiery debris, and in one instance a tsunami. I believe it was 2 or 3 large ships exploding at various times starting off with a French freighter stuffed with ammonium nitrate.

[flagreen]

Here's a link to a story with photos of the skyway incident. Actually the fall was 600' and death toll over 30.

http://www.rushw.com/skyway/sky4.html

[Cliptin]

It happened because the brease down the river blowed in small shots of a frequency which matched te internal (inherent) frequency of oscillation of the bridge.

The suspension cables in particular. Folks used to drive out to ride the bridge. The movie you see is the day the wind was enough to tear it apart.

[JKKJ]

The Int'l Space Station has to correct regularly for oscillations that slowly build due to the ultra-low-frequency gravitational waves from the Earth by occasionally firing certain small stabilisers situated around the spacecraft for extremely brief periods.

This sort of stuff just amazes me. I have a hard enough time figuring how to replace a post in my house. :o

[Rocco Siffredi]

The Tacoma bridge incident was (and still is) a textbook-scenario for civil engineers.

True. My physics teacher showed us the video, and then made us solve some problems related to it. (something about how long the support cables had to be to change the fundamental frequency or something or other. :eekers:

[Mercutio]

That must be some kind of physics class rule. I've saw that film in both high school and college physics and even had to do the same problems (uh, but using different methods for solution).

[Prof.Wizard]

Merc, what college degree you have?

[Mercutio]

Computer Science. Minored in English Lit.
Amy's also mad at me because I got a higher MCAT score than she did, though.

[Splash]

Here's a link to a story with photos of the skyway incident. Actually the fall was 600' and death toll over 30.

http://www.rushw.com/skyway/sky4.html

The 600 feet was the distance the car sailed through the air before hitting the water. The bridge height from road surface to water is definitely nowhere near 600 feet. I'm sure there must be statistics somewhere out there on bridge heights, but I just don't have the time at the moment to go digging around. Being an experienced aircraft pilot, I'd have to say the roadway height above the water is around 60 to 70 meters which is something like 200 feet.

[Prof.Wizard]

Chilling story indeed. Thank god it happened some two months before I got born... :-?

[flagreen]

Splish Splash -

You are correct, I found this web page which lists the vertical heighth of the new bridge at 193'. As I recall the old spans were slightly lower than the new one is.

HAPPY NOW? YOU'VE HUMILATED A HARMLESS OLD MAN! YOU'VE PROVED HIM WRONG AND REMINDED HIM THAT HE'S NOT HALF THE MAN HE USED TO BE. WHAT'S NEXT? COMING TO MY HOUSE TO KICK THE WALKER OUT OF MY HANDS? HIDE MY TEETH FROM ME? TIE A KNOT IN MY COLOSTOMY BAG TUBE?

[Handruin]

I didn't take physics, but we discussed that same bridge in music theory I believe. Something to do with resonating frequencies. :)

Wasn't the nickname of that bridge Galloping Girdy, or something like that?

[Splash]

Splish Splash -

You are correct, I found this web page which lists the vertical heighth of the new bridge at 193'. As I recall the old spans were slightly lower than the new one is...

Most of the "big" coastal bridges have roughly a 200 feet clearance between the water and the bottom of the bridge over the main ship channels. I've long known that the San Francisco Golden Gate Bridge has roughly 200 feet of clearance for ships -- which, by the way, isn't enough for a few aircraft carriers. Having been over the Golden Gate bridge many times and the nearby Oakland Bay bridge -- which is more interesting bridge in many way, what with the tunnel through Treasure Island as you are ascending / decending the bridge -- the bridge somewhat near here called the Hartman bridge, the Tampa Bay Skyway bridge, they all have approximately the same clearance above the water.

As for a freestanding 500 or 600 feet high bridge, that would be a seriously expensive bridge to build and without any justification since there are no ships anywhere near that high. I've been over the Hoover Dam, which is not exactly a bridge, but I believe it was about 600 feet down to the river below on the downstream side of the dam. I believe there are a few bridges here and there around the world that span canyons which are a few thousand feet deep. I recall going over a bridge once in Utah (though it could've been Wyoming) on an Interstate highway that was so high above the river below that you could barely make out anything below, much less the river. That was probably close to 500 or 600 meters high.



HAPPY NOW? YOU'VE HUMILATED A HARMLESS OLD MAN! YOU'VE PROVED HIM WRONG AND REMINDED HIM THAT HE'S NOT HALF THE MAN HE USED TO BE. WHAT'S NEXT? COMING TO MY HOUSE TO KICK THE WALKER OUT OF MY HANDS? HIDE MY TEETH FROM ME? TIE A KNOT IN MY COLOSTOMY BAG TUBE?

Don't worry, I'm probably older than you. I'll be 50 years young 4 months from now.

[Cliptin]

Hey, Looks like we've got a contest. I wonder if CNN-sport can commentate orthopedic walker races. At what age do you begin to fart dust? :o

[flagreen]

Splash,


Don't worry, I'm probably older than you. I'll be 50 years young 4 months from now.

I will 51 this November youngster. You have mail coming in four months from AARP to look forward to. :)

[Splash]

Hey, Looks like we've got a contest. I wonder if CNN-sport can commentate orthopedic walker races. At what age do you begin to fart dust? :o

Cliptin: Unfortunately, I have no problem winning distance races or sprints with the "average" 20 ~ 30 year olds. People that don't know me well, or at all, probably assume I'm roughly a 32 ~ 36 year old person. I have somewhat long hair, not balding, and not grey. I'm 6-foot 1-inch tall, also not fat at about er... 190 pounds.

I was even accused of being an "X-er" last year as well (Generation "X" = born in the mid 1960s to about 1980 or so). This was at work after a presentation I did; it was all in good nature, though. My "acuser" -- a person that I had only met once before -- made the remark "all you X-ers have these crazy ideas... blah blah blah." I started laughing and told him that according to sociologists, I'm supposed to be a "Boomer," and probably older than you might think. Thinking that my "accuser" was probably about 50 ~ 55 years old, I challenged him to show his drivers license at the same I showed mine -- showing our legal ages. He did, and Surprise Surprise, I actually ended up being almost 2 years OLDER than he was! This guy and his buddy just about laughed their @sses off.

[Prof.Wizard]

I didn't take physics, but we discussed that same bridge in music theory I believe. Something to do with resonating frequencies. :)

Exactly that. Resonance.
(the "tuning" I said)

The same will happen if you play the Intel tune near an AMD... it will vibrate to death... :lol:
(evil Intel engineers have discovered the secret frequency of Athlon's materials)