35W bridge in minneapolis collapses

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Discussion Overview

The discussion centers around the collapse of the 35W bridge in Minneapolis, exploring the immediate aftermath, potential causes, and the implications of infrastructure safety. Participants share news updates, personal connections to the bridge, and speculate on the reasons behind the collapse, including structural integrity and maintenance issues.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Initial reports indicate that cars fell into the water as a result of the bridge collapse, raising concerns for those who may have been trapped.
  • Some participants express shock and concern for the safety of individuals involved, particularly mentioning a school bus that narrowly avoided the gap.
  • There are conflicting reports about the number of casualties, with estimates ranging from 7 to 9 dead and many still missing.
  • Speculation arises regarding the cause of the collapse, with some suggesting that the bridge was undergoing repairs and may have had structural deficiencies.
  • Participants discuss the possibility of vibrations from construction or traffic contributing to the failure, with references to the bridge's classification as "structurally deficient."
  • Some participants mention that terrorism has been ruled out, while others question the reliability of the bridge's recent inspections.
  • There is a debate about the nature of the collapse, with some arguing that it was sudden and others suggesting it may have involved a series of failures.
  • One participant notes that the bridge's design might not have been adequate for the traffic load it experienced, raising questions about engineering standards.
  • Concerns are raised about the broader implications of infrastructure safety in North America, with references to a lack of political action on maintenance issues.

Areas of Agreement / Disagreement

Participants express a range of views on the causes of the collapse, with no consensus reached. While some agree on the structural deficiencies and maintenance issues, others focus on the immediate human impact and recovery efforts.

Contextual Notes

Participants mention various assumptions about the bridge's condition, the nature of the collapse, and the adequacy of past inspections. There is uncertainty regarding the exact circumstances leading to the failure and the implications of the bridge's structural status.

Who May Find This Useful

This discussion may be of interest to those concerned with civil engineering, infrastructure safety, emergency response, and public policy regarding transportation systems.

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"A bridge over the Mississippi River in Minnesota has collapsed, sending cars into the water, The Associated Press reports" - CNN. Hope everyone here is ok! My sister and brother-in-law take it every day, but they phoned us ok.
 
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Good grief.

Do you have a link to the story?
 
There's a little more at Yahoo:

http://news.yahoo.com/s/ap/minnesota_bridge_collapse

I hope no one was killed.
 
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Mallignamius said:
There's a little more at Yahoo:

http://news.yahoo.com/s/ap/minnesota_bridge_collapse

I hope no one was killed.

Reports of cars under the collapsed bridge, that doesn't look good
 
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Thats very shocking to see. Your right it doesn't look good for some, but was glad to hear the school bus made it.
 
I have a friend in Minneapolis that takes that bridge.
 
Yeah, I saw this on the news, I hope there aren't too many serious or fatal injuries. I wonder what caused it.
 
Wow, those people were in their car and fell 64 feet into the water. Thats like driving into a brick wall at 100mph.

Thats a bad way to crash because the road literally fell from under the car. A car is not designed for that kind of an impact.
 
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  • #10
"Recovery efforts have been halted because of darkness"

CNN says "Recovery efforts have been halted because of darkness". Are they serious? Night light at football games can make the whole field look like it was noon on a sunny day. It's my understanding that there might still be dead people in the water. Terrible tragedy.
 
  • #11
On the bbc, they were reporting 50 cars in the water -- there's sure to be people killed :frown:

Also, the story of a school bus, with 60 kids on board, which just stopped before/on the gap (http://www.bbc.co.uk/mediaselector/check/player/nol/newsid_6920000/newsid_6927100?redirect=6927160.stm&news=1&bbwm=1&bbram=1&nbwm=1&nbram=1&asb=1)

http://img381.imageshack.us/img381/4146/44034277bridgecollapse4ji4.jpg http://img381.imageshack.us/img381/7104/44034283slope220apsl4.jpg

http://news.bbc.co.uk/1/hi/world/americas/6927113.stm (e2a: http://photos.denverpost.com/galleries/newsgallery.html#id=1351&num=1)

:frown:
 
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  • #12
Said on the radio an hour ago that the death toll is 7. Looks like a lot of people survived the impact.
 
  • #13
They just mentioned 9 people were killed, and 20 people are still missing. They mentioned that the effort this morning has changed from one of rescue to one of corpse recovery.

They are saying that the death toll is expected to rise later on today.
 
  • #14
Are they suspecting terrorism? I mean, the bridge was given the OK about 3 years ago after an inspection. It just can't fall, right?
 
  • #15
No one mentioned an explosion before it collapsed, just that it suddenly gave way.

Terrorism has been ruled out, it said that just as I was typing this. :smile:
 
  • #16
Schrödinger's Dog said:
No one mentioned an explosion before it collapsed, just that it suddenly gave way.

Terrorism has been ruled out, it said that just as I was typing this. :smile:
When I first heard it on the radio this morning, it sounded like an earthquake -- the people were saying it started shaking then they went into free-fall.
 
  • #17
Earthquake? Minneapolis? The shaking was probably just the bridge giving away.
 
  • #18
According to the news reports the bridge was under repair at the time.
 
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  • #19
cyrusabdollahi said:
Wow, those people were in their car and fell 64 feet into the water. Thats like driving into a brick wall at 100mph.
Just to put a little perspective on this, they could not have fallen at free fall velocities. It's a collapsing bridge, not a disappearing bridge.
 
  • #20
ranger said:
Earthquake? Minneapolis? The shaking was probably just the bridge giving away.
Yeah -- I don't know that part of the US very well (apart from the airport), but thought it stange.

Like you say, the bumps people were reporting were probably the bridge giving in stages.

bbc: why?
 
  • #21
BEFORE:
i35wmiss02.jpg
AFTER:
ekjl.jpg
Who knows what caused it... the bridge was undergoing resurfacing and other 'minor' construction. Not sure what that means, but it might have had something to do with it. A failure of just one of those truss connections could cause the whole thing to come down.

They said it was bumper to bumper traffic just before the collapse, but it was mostly small cars. Bridges are designed to carry fully loaded tractor trailers bumper to bumper which is considered the worst case loading. I don't think this was the highest load the bridge had seen in it's 40 year lifetime. It must have been either some kind of material failure (corrosion, fatigue) or something happened with the construction that was going on.

Lower maintenance is a big reason that a lot of bridges like this are made of concrete now instead of steel (see adjacent bridge).
 
  • #22
  • #23
That video on cnn's website is quite a mouthful to grasp. Its just unbelievable to see steel and concrete (?) in such a state.
 
  • #24
My friend in Minneapolis just wrote me, he had this to say.

They installed an automatic de-icing system a few years ago and that is corrosive material (no one mentioned this) and it's been quite hot, that could have placed unusual expansion stresses in the steel truss structure. The failure happened at one point and the rest of the collapse was cascade or chain reaction. It's clear it was on the west (south end) bank side and from my inexpert opinion looking at the wreckage from the TV videos, the down stream side failed first and the bridge torqued and collapsed.
 
  • #25
ranger said:
Are they suspecting terrorism? I mean, the bridge was given the OK about 3 years ago after an inspection. It just can't fall, right?

Sure it can, it just did. 3 Years ago is a LONG time ago. But they said on the news it was inspected last in 06, and probably its next inspection for 07 was coming around sometime soon. I am not sure where you heard 3 years ago from.

Whoever the engineer is that signed off on the bridge, its going to be his ass.
 
  • #26
DaveC426913 said:
Just to put a little perspective on this, they could not have fallen at free fall velocities. It's a collapsing bridge, not a disappearing bridge.
As we know from debunking 9/11 conspiracy theories, structural failure is generally an all-or nothing thing. When the structural members fail, the bridge would have essentially dropped in freefall. Even when the failure is buckling instead of breaking (this one probably had both), the ability of the members to hold up the weight/resist the fall drops by many orders of magnitude.
 
  • #27
ranger said:
Are they suspecting terrorism? I mean, the bridge was given the OK about 3 years ago after an inspection. It just can't fall, right?
Not a cheery through, but this bridge was on a federal list of "structurally deficient" bridges...a long list:
He says investigators are sure to look into whether work crews or passing trains caused excessive vibrations on the steel-truss span, which was deemed "structurally deficient" on a federal list of bridges.

"A structurally deficient bridge might be one not adequate for the traffic it takes, but not necessarily dangerous," Burnett tells the paper. "But a lot of structurally deficient bridges are dangerous."

The feds have information about deficient bridges. So does the group that represents civil engineers. It says: As of 2005, 156,335 of the nation's 595,363 bridges, or 26.3%, were structurally deficient or functionally obsolete, as compared to 34.6% of all bridges in 1992.
http://blogs.usatoday.com/ondeadline/2007/08/expert-points-t.html
 
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  • #28
Schrödinger's Dog said:
Terrorism has been ruled out, it said that just as I was typing this. :smile:

Yeah, in a country of paranoia that's the first concern. :rolleyes:

It's insane though. The infracture issue is happening all over North America. No politician wants to take anything seriously, so maybe we will an INFRAC Concert like Earth and that 8 convert.
 
  • #29
I like how the newspeople are asking, "well, they were jackhammering near the bridge, do you think that might have been a cause?"

Just ONCE, Id like to see someone say, "No,...its your bullsh!t reporting that caused it to fall". They have animations of the bridge falling, actual footage. Probably a bridge falling expert to comment on it. Of course, "terrorism was ruled out". Really, you think so?

The people on the news are idiots. One guy on cnn.com was on the bridge and he was talking about it. The reporter said "wow, you're very calm, Id be panic stricken"...yeah were all a bunch of idiots that run around like our heads chopped off everytime something happens. GIVE ME A BREAK. Then he said "I guess that calm comes over you when you have a near death experience".
So the guy just looked at him, gave a little laugh and said "Yeahhh...I guess so".

<smacks myself in the forehead>

A damn bridge fell. Its not that hard to comprehend if you have a brain in your head. This kind of media hype gets under my skin.

[/rant]
 
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  • #30
Crappy engineers, crappy maintenance.
 

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