Minneapolis bridge collapse

[Marks256]

About a two hour drive from my current location, a bride in Minneapolis, Minnesota, USA collapsed sending cars into the river below. Currently there is one reported death.


https://www.chron.com/disp/story.mpl/front/5019944.html


The news is covering it on every TV station here.


There is no reason to believe at this time that is was terrorism.

 

[xxxxxxxxxxxxxx]

yer i heard here in oz, 9 people now.. thats got to be pretty tough, collapsing bridges and you're on the bridge...

 

[justDIY]

thats a terrible example of corporate greed and bureaucratic corruption at work!

the US is touted to be the most technologically advanced and richest country in the world, yet we let our infrastructure decay to the point of fatality.

 

[Marks256]

yer i heard here in oz, 9 people now.. thats got to be pretty tough, collapsing bridges and you're on the bridge...

Actually, it was 7 people for a while (estimate by police), but just this morning, it was downgraded to 4.

 

[j.p.bill]

As long as there is an external enemy, allowing minor things like national infrastructure to decay is perfectly acceptable. Do you want good roads and bridges, or be perfectly safe from terrorism?

You might also not that defense contractors earn higher profit margins than construction firms (Mr. Cheny's being exceptions).

Also, historically speaking, there are still wealthy interests that are very dedicated to undoing all of the New Deal programs instituted by FDR. Be careful of who you vote for.

 

[Optikon]

As long as there is an external enemy, allowing minor things like national infrastructure to decay is perfectly acceptable. Do you want good roads and bridges, or be perfectly safe from terrorism?

You might also not that defense contractors earn higher profit margins than construction firms (Mr. Cheny's being exceptions).

Also, historically speaking, there are still wealthy interests that are very dedicated to undoing all of the New Deal programs instituted by FDR. Be careful of who you vote for.

Allowing infrastructure to decay is acceptable?!?! I don't think so!

The people responsible for good bridge designs and upkeep are not the same ones responsible for fighting terrorism. So we can both be safe and have good bridges.. geesh.

 

[Hank Fletcher]

As long as there is an external enemy, allowing minor things like national infrastructure to decay is perfectly acceptable. Do you want good roads and bridges, or be perfectly safe from terrorism?

I think what he's trying to say is that as long as the myth of an external threat is perpetuated, the few folks in position to gain from that perpetuation will go to no end of sacrficing dollars, people, or morals in the name of "victory." In short, 9/11 was a blank cheque, which makes you wonder who had the greatest motivation to orchestrate the whole thing.

I can't stand it anymore. George paid Osama to train terrorists to fly into the twin towers. There, the truth is out. We all know it, although the proof may never be found. Speaking of which, why are Canadian soldiers looking for Osama in Afghanistan?

 

[justDIY]

even before "terrorism", the govt looked the other way as infrastructure crumbled.

power grid; a mess
interstate system; crumbling
arterial roads; beyond crumbling
rail system; hardly used at all, rusting away
sewage; overstressed, constantly dumping sewage into bodies of water / rivers

terror has given law makers a good excuse to ignore the problems at home. it's not just the people at the top. I'm involved in my local government, and here in the North woods of Michigan fear mongering is causing millions to be spent on futile efforts to make us "safe".

 

[Andy1845c]

I have a feeling that it may have not been a lack of inspection or lack of maintenance, but possibly the concenterated weight of constuction equipment and piles of sand on the bridge deck. They were doing a concrete overlay of sometype, and had some lanes closed. Somone on the news siad that there were large piles of sand and gravel piled near where it looks like the collapse started.

Several dumptruck loads of sand (one of the heavist things you can haul) could easily exceed several hundered thousand pounds. A five axle tractor trailer can't exceed 80,000 in MN, and even then, you have to have the weight spred over the axles. Plus there seemed to be alot of heavy machinery on the deck when it happed, plus bumper to bumper traffic. How much weight can one of these structure really take?

 

[Marks256]

I have a feeling that it may have not been a lack of inspection or lack of maintenance, but possibly the concenterated weight of constuction equipment and piles of sand on the bridge deck. They were doing a concrete overlay of sometype, and had some lanes closed. Somone on the news siad that there were large piles of sand and gravel piled near where it looks like the collapse started.

Several dumptruck loads of sand (one of the heavist things you can haul) could easily exceed several hundered thousand pounds. A five axle tractor trailer can't exceed 80,000 in MN, and even then, you have to have the weight spred over the axles. Plus there seemed to be alot of heavy machinery on the deck when it happed, plus bumper to bumper traffic. How much weight can one of these structure really take?

Yeah. They were also talking about the fact that the last inspection of the bridge's structure barely passed.

 

[audioguru]

I think the bridge broke because of a combination of events:
1) There was a train running under it. Did the train de-rail and hit a support?
2) Earthquake?
3) All the cars were driving on it then they suddenly came to a stop and forced the bridge to move off its foundation?

 

[justDIY]

an earthquake in Minnesota?! that's about as likely as an earthquake in Ontario.

sure they happen, but not very often and they're not at all powerful.

the bridge collapsed for one of these reasons, or a combination

1) the bridge was designed and built in the sixties and never reinforced to carry todays excessive truck freight loads and extreme gridlock traffic. decades of abuse and the sloppy work of lowest-bidder contracting companies led to its failure.

2) the bridge was built in the sixties and other than resurfacing it when absolutely necessary, no major overhauls were ever conducted. The local government claims they don't have the money to fix state roads, the state claims they don't have the money to fix federal interstates, the feds claim they don't have the money to fix state roads.

Rest assured the government will come up with plenty of reasons why they weren't to blame after spending millions of dollars hiring consultants and investigators; paying them to say the "right thing."

 

[audioguru]

It is time for cars to be built with ejection seats to be activated when it drives on a collapsing bridge.

 

[justDIY]

It is time for cars to be built with ejection seats to be activated when it drives on a collapsing bridge.

ROFL ... I agree 100%

 

[mneary]

The people responsible for good bridge designs and upkeep are not the same ones responsible for fighting terrorism.

But they are competing for the same money, and guess where we're "investing" a trillion dollars. Not on highways.

In 2006 alone the US lost 42,642 lives (1.6 million injured) on the highway. In the past 10 years we've had more than 125 highway deaths for every terrorism death. [my calculations based on NHTSA data] Let's find a country to blame, and then we can invade them.

 

[Marks256]

I think the bridge broke because of a combination of events:
1) There was a train running under it. Did the train de-rail and hit a support?

Hmm, never thought of that one...

2) Earthquake?

The U.S. Geological Survey reported no seismic activity in the area.

3) All the cars were driving on it then they suddenly came to a stop and forced the bridge to move off its foundation?

It was bumper to bumper traffic, which was at a crawl (10M/h). I think that would be highly unlikely.




As a friend of mine put it; Standing rush hour traffic + hot day (expanding) + construction crew on the lanes + known structural cracks on decking.

But, we won't know for sure for some time now.

 

[Andy1845c]

I think the bridge broke because of a combination of events:
1) There was a train running under it. Did the train de-rail and hit a support?

I haven't heard that the train was moving at the time of the collapse. I think that track goes to the Pilbury mill or somthing and isn't used much anymore. Even if it was moving, the speed would have been very slow due to the downtown location.

 

[Andy1845c]

1) the bridge was designed and built in the sixties and never reinforced to carry todays excessive truck freight loads and extreme gridlock traffic. decades of abuse and the sloppy work of lowest-bidder contracting companies led to its failure.

Speaking of the design, why was it built with no center pilons for support? Looking at the pictures of it before the collapse, it looks rather wimpy compared to the 10th St. bridge that is right next to it.

How do they decide on how much weight the bridge needs to be able to hold up? Do they go by a worst case senerio of bumper to bumper fully loaded dump trucks? Average traffic? What about these overlays. Unless a layer of deck is milled off, they would add a huge amount of extra weight.

Seems like with no center support, every pound of weight has to be trasfered down to those 4 cement pilons on the river banks. If anything gets overloaded or breaks, it has to come all the way down. It can't partily collapse or bend or sag or anthing.

 

[ljcox]

When I studied mechanical engineering, we were taught to design beams such that they would carry at least 3 times the expected load.

But in time, rust of the steel reinforcement rods, concrete cancer, etc. can weaken a structure hence the need for frequent inspection.

 

[Adrnin]

sorry to hear that