Reports about bridge wobble days before the collapse

[sabra]

http://www.startribune.com/10204/story/1345092.html

<snip>

Reports about bridge wobble

NTSB investigators also said they have interviewed the construction workers who were on the I-35W bridge at the time of the collapse. It is only the second time in almost a quarter of a century that a highway bridge in the United States has fallen without an immediate cause such as a earthquake or a collision.

Some workers said that the bridge had been wobbling unusually in the days before the collapse, according to Minneapolis police Sgt. Tim Hoeppner. With every layer of concrete that they removed, the bridge would wobble even more, they told him.

Rosenker would not address that issue, or go into specifics about reports that the bridge had poor inspection ratings, but he said that would be part of the investigation. "We're going to take a look at that," he said.

[opihimoimoi]

1. Sure don't look good at all...I smell Malfesance, Peterism, and Ignorance

[keith the dem]

2. Interesting

I'm wondering if there was reduced torsional resistance because of the removed concrete deck. The bridge twists, a connection breaks or slips, and cabluey, a progressive collapse.

[followthemoney]

24. For all the attention the wobble brought, there could have been

a tera-ist cell cutting into the structure with piano wire since 1989. Remember, they have a thousand years for revenge.

[Hepburn]

3. So the construction workers noticed an unusual wobble...

...in the days before the collapse. Did they tell anyone, report it, etc? And, if so...what steps were taken in response?

[malaise]

4. The bridge had been wobbling unusually

and no one reported that? WTF??

[seemslikeadream]

5. THE BRIDGE HAD BEEN WOBBLING!

WTF????

[malaise]

11. Good point

any wobble is a sign of problems.

[Hepburn]

12. Exactly....

...I cannot imagine ANYONE who would think that a bridge wobbling was something to be ignored. Ummmm...scratch that: The govenor of MN apparently felt different. So make that an ALMOST and not an EVERY.

[malaise]

13. I'd love to hear from the DU engineers

trucks full of concrete on a bridge that was wobbling - damn!!

[seemslikeadream]

14. They closed this bridge for 20 months when it wobbled

http://news.bbc.co.uk/2/hi/uk_news/england/london/4400010.stm

[malaise]

16. They actually care about their citizens

Check this out
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=389x1525841

[Gregorian]

15. It's all guessing until the data and or evidence comes in.

Lots of guesses. I can imagine what happened. And it may or may not be right. An underdesigned bridge that was expanded, combined with poor maintenance. A member that became detached, and the resultant failure of a critical component. Something like that. But I also have to wonder about why that bridge fell almost simultaneously at both ends. Maybe that was meaningless. Or even just the way that video made it seem.

They'll try to reconstruct the failure using the software they've developed. And they'll be looking for joints in the failure area that have marring. A sign of repeated movement before the failure. A sign that a part of the supporting structure that may have been detached before the bridge crashed.

But just removing the downed bridge will be a daunting task. Sectioning into pieces that can be lifted.

But there is little room for guessing in engineering. Just arduous step by step procedure. It might be years before we hear the answer. It'll be a combination of things, I suppose.

So there, I've said almost nothing.

[Bitwit1234]

6. Phew-lenty was given a bill to repair the bridge and he vetoed it.

His head of the DOT - who he also picked to be his Lt. Gov told him it wasn't needed. They needed the money they would spend for the new stadium and the millions they earmarked to be used to protect the republicans when they invaded Minnesota next year for their convention.

By the way. Going into a super market in my MN hometown some lady stopped me and asked about the bridge. Then she got all excited and said "and the president was here". I looked outraged and said "as far as I am concerned he could have his photo-ops taken in the Everglades". And thought to myself fighting off the gators. Everglades was the first thing that popped into my mind. I don't know why.

[donsu]

7. because brother Jeb has been trying to kill it

nt

[Hubert Flottz]

8. I wondering if they had a bunch of concrete trucks lined up on a

small area on that bridge deck that evening unloading and waiting to unload? Those trucks back up quickly sometimes, if something goes wrong when the contractor is making a big concrete pour. A concrete truck loaded with a full load of concrete is VERY heavy. I saw one concrete truck laying in the wreckage upside down near the lock wall and it just made me wonder, how many of those were on the bridge at one time.

[karlrschneider]

9. Seems like a corollary of the First Rule of Holes should have been used there...

:eyes:

[AwakeAtLast]

10. 5th K & R for you!

If a bridge wobbles, that's a bad sign - for most people. :eyes:

I think the details are going to get hairy.

[proud2BlibKansan]

17. One of my conspiracy theory friends emailed me today

and said she heard that the construction workers had complained about the bridge vibrating for days before the collapse. I decided it was just another of her conspiracy theories.

Also, she had heard that they were taking cell phones away from people on that bridge after the collapse. I wonder if we could check that out.

[The Vinyl Ripper]

18. What engineer or supervisor in his right mind..

Would listen to the babblings of construction workers who were merely physically present on the site?

We all know anyone who works with their hands is an idiot or they would be clicking a mouse in an office somewhere for half the pay.

[Tracer]

19. "Wobbling" is a kind of vague term.

I've been under the impression that bridges have a certain "give" to them.

Last Thanksgiving Day, in the middle of an enormous traffic jam, I was stuck in the middle of a large bridge (over a large river) for over a half an hour.

As the traffic creeped and crawled over the bridge, the darn thing was rocking and bumping up and down (and THIS is a bridge that had just finished being repaired!!!)

[BlooInBloo]

20. And this, class, is the difference between *retrospective* and *prospective*.

[sandnsea]

21. Union?

I think something we forget is that a strong union movement also gives workers the protection they need to make the complaints regarding safety as well. You wouldn't find union workers slapping lead paint on kids toys either.

[slackmaster]

22. The bridge wobbled, Bush just bobbled

:shrug:

[intaglio]

23. Many site workers

have more experience, if less education, than construction engineers; if the workers were noticing a wobble and reporting it then there was reason to be concerned.

The big problem is that the investigators will easily find a proximal cause (a failure of a corroded tie or subsidence at one of the bridge piers) but will struggle to find the events that led to that catastrophic failure.