Breaking: Bridge Collapse in Minneapolis

KSTP TV 5/ME | 8/1/07 | Me

[ButThreeLeftsDo]

Just turned on the news. 35W bridge collapsed in the Mississippi River. Cars, trucks, semis.....

Fires burning, tanker trucks, at least one school bus, more than ten cars......

Just now breaking.......

[Lijahsbubbe]

Causes?

I'm sure I'll get flamed but I'm sticking with the weather. We've had nineteen straight days of 90 degree weather. Not an engineer (by any stretch) but it doesn't seem far-fetched to think that the river bank drying up and expansion due to heat could cause problems.

[cookcounty]

What? Michael Moore is throwing a bash for first responders? Hows about some context?

[editor-surveyor]

"They also interviewed former state Transportation Commisioner (and Democrat) Elwyn Tinklenberg who said that this sort of thing was overdue because of our inability to properly fund our roads and bridges."

And that inability is directly caused by diverting road fuel taxes to Bolshevik mass transit projects.

[UCANSEE2]

Crews had been ‘grinding’ out the old concrete, to prepare for pouring new.

There were concrete trucks (very heavy loads in concentrated areas) all over the bridge during bumper to bumper traffic (max vehicles on bridge).

Maybe somebody ground down tooooooo far. It would be like a row of dominos.

[pillut48]

Found this link on DU with pics. (Gotta give credit where credit is due!)

[PAR35]

If scouring were a problem it would have happened decades ago.

It took about 50 years for the US 51 bridge in Tennessee.

[jeffers]

The deck can act as a membrane for lateral stability, but that adds greatly to the dead load. In mechanical effect, you have a zigzag series of braces to transfer the lateral loads doing it that way, whereas a very few diagonals connecting the cantilever truss systems accomplish the same objective.

This is what the pictures tell me:

[1COUNTER-MORTER-68]

“Hey,,,How much SALT is used on that bridge in the winter ??...”
That would be a point if it were a deck failure, but I didn’t see anything that looked like a deck elongation happened.
~~~~~~~~~~~~~~
JMHO : This sounds more like rivet/iron failure the more info that comes out,,,
FYI : You could pull the whole deck off of that or any other bridge and the iron would still be standing,,,

Salt corrodes rivets...

[raygun]

Are you trying to tell me that the British built some tower in '97 to commemorate your arrival, and then, because you where there during the tower's construction, the metal framework expanded some 1" and that the whole region experienced a heatwave due to the expansion of joints and materials (all as a result of your presence)? I find that a little far fetched to say the least.

[TornadoAlley3]

http://keyetv.com/video/?id= href=”mailto:29669@wcco.dayport.com”>29669@wcco.dayport.com

video of bridge collapse

[fred4prez]

When the bridge dropped, objects and people dropped slightly later, being momentarily suspended in mid-air, making it appear that things were flying upward. No blast.

[The Legionary]

The water can’t be too deep since most of the bridge is still above water. Also, due to the drought conditions in most of the state, the Mississippi is running at about a third of its normal water flow.

[concretebob]

Blow counts, stroke and ear plugs, Baby!!!!

We used a D19-42 Very old...but, cleaner than the B-E I worked with in 1976

[Abigail Adams]

Cool! One report specified fatigue cracking on one of the approach spans (not the spans that go over the water).

[mplsconservative]

Not going to flame you, but this bridge is 40 years old and I think these conditions have existed before in the bridge’s history.

I’ve been a passenger, or driven across this bridge since I was 7 years old. I’m glad you and your family are okay and were together when this horribe thing happened.

It’s been a tense night for many of us in the metro.

[burzum]

Hey,,,How much SALT is used on that bridge in the winter ??...

The bridge had an automatic deicing system. Of course, cars could track salt onto the bridge which could eventually drain into the supports. Chloride corrosions are some of the worst types of corrosion known (especially chloride stress corrosion cracking). Presumably the State would inspect/clean periodically to prevent corrosion failures. Of course, that still needs to be determined (if it was actually the cause).

[DAVEY CROCKETT]

Bridge Collapse in Minneapolis A truck driver just called in to the Royle James show and said that they spray calcium ?something? (maybe magnesium) on the highway up north to de-ice them.

This spray eats at the wiring under the trucks and that he had to have his truck washed everytime he came home to get the stuff off. Here it is this is my bet on the falling of the bridge.... it fell to even.

Primer on the Use of Magnesium Chloride as an Ice

http://www.snowplowing-contractors.com/mag_chloride.html

[mware]

LOL, no I was just commenting on the fact that heat does cause a change in steel. The reason I recall it is because the UK is not know for hot weather and while I was there it broke a heat record set in 1659.

[jeffers]

The problem began on the right side of that picture.

Pier footing, pier or steelwork.

Bank on it.

I don’t say that very often, but pictures don’t lie.