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Discussion Starter · #1 ·
Aug 1, 2007 7:57 pm US/Central
I-35W Bridge Collapse Into Mississippi River
Slideshow: I-35W Bridge Collapse

(WCCO) Minneapolis New at 7:58 p.m.



Workers from a St. Michael company called Progressive were working on the bridge



Paul McCabe, a spokesman with the FBI in Minneapolis, said agents responded to the bridge and would conduct any necessary investigations.

"Although it is much too early to make any determination of the cause, we have no reason at this time to believe there is any nexus to terrorism," he said.

Brian Turmail, a spokesman for the U.S. Department of Transportation, said the department is getting briefed on the collapse, but it was mainly being handed by local agencies.

"Right now the focus is on saving lives," he said.

All four lanes of the Interstate 35W Mississippi River bridge near University Avenue has collapsed into the river and onto businesses underneath the highway at 6:05 p.m. Wednesday.

Emergency Management officials have confirmed three people are dead and at least 20 people have been transported to local hospitals.

According to reports from the scene, crews on the Mississippi River are no longer in rescue mode but recovery mode.

Cars are still on the bridge.

According to a structural engineer who spoke with WCCO-TV's Don Shelby, it doesn't appear to be a concrete failure but that the steel failed.

Some people are stranded on parts of the bridge that aren't completely in the water.

"I couldn't event even count how many cars went off the bridge," said one woman who witnesses the collapse from her apartment. "We're helping people on backboards."

She said she pulled 12 out of river and said there were people that were deceased.

WCCO-AM reported that one body was scene being pulled from the area, covered with a blue sheet.

A tractor-trailer is still on fire at the collapse scene with plumes of smoke clouding the sky.

"I thought it was just construction going on ... it was a free fall all the way to the ground," said one person who was on the bridge at the time. "Thank God I was wearing my seat belt. The only thing I was hit was the steering wheel."

According to that same witness it was bumper to bumper traffic when the bridge collapsed.

Some cars are still precariously perched on the bridge. Sections of the bridge are mangled, some are pointing up in the air and some are in the river.

"My truck got completely torn in half," said Gary Bavanaugh, who was on the bridge when it collapsed. "The bridge started shaking and it went down fast."

Bavanaugh said he was headed northbound on I-35W when he heard a huge rumbling and he saw a huge cloud of white dust as the bridge collapsed. He had his seatbelt on and said if he hadn't, his head would have gone through the windshield.

Bavanaugh said a school bus full of children was ahead of him. He got on the bus and helped children, who he estimated to be 8-12 years old, off the bus and off the bridge.

"It is just horrific," said witness Marilyn Franzen, who saw the bridge collapse. Franzen said she saw a school bus that managed to stop before the going over the edge of the bridge that she said was carrying 20-30 children.
wcco.com - I-35W Bridge Collapses Into Mississippi River

the video shows the complete devastation. Both directions.

Incredible.....
 

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I've been glued to the TV watching this terrible event. Imagine if all the lanes had been open.
 

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Discussion Starter · #5 · (Edited)


Look how close that bus was..20 kids on board :eek:

detailed photo gallery here

The World | The Australian

The one engineer interviewed thought it might be thermal stress.
 

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There seems to be a difference of opinion as to whether there were problems with the bridge. One report I read said there were no immediate or structural problems with the bridge but another one was quoting that in 2005 inspectors thought the bridge was "structurally deficient". That it was rated at 50 percent on a scale of 0 to 100 percent, which meant the bridge might need to be replaced. I guess the finger pointing has started.


MPR: Collapsed Mississippi River bridge passed last inspection

Captain's Quarters

See story under "Was The Bridge Deficient?"
 

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Discussion Starter · #8 ·
I keep thinking I saw one of those enormous liquid concrete transports buried in the rubble but cannot get a photo that shows it clearly.
Those trucks are enormously heavy. Given it was rush hour and stop and go traffic one wonders if that was the "straw" that broke the bridge.

That concentrated weight may well have not triggered anything if it was moving quickly but if stopped or moving slowly over a weak point.....

Those trucks get into the 80 ton range.

Clearly it's a problem nationwide

Truck Loading and Fatigue Damage Analysis for Girder Bridges Based on Weigh-in-Motion Data
J. Bridge Engrg., Volume 10, Issue 1, pp. 12-20 (January/February 2005)
Ton-Lo Wang,1 M.ASCE; Chunhua Liu,2 M.ASCE; Dongzhou Huang,3 M.ASCE; and Mohsen Shahawy,4 M.ASCE
1Professor, Dept. of Civil and Environmental Engineering, Florida International Univ., Miami, FL 33199.
2District Two Bridge Structural Engineer, Florida Dept. of Transportation, 710 NW Lake Jeffrey Rd., Lake City, FL 32055.
3Senior Research Scientist, Stractural Research Center, Florida Dept. of Transportation, 2007 E. Dirac Dr., Tallahassee, FL 32310; and Professor, Dept. of Civil and Architectural Engineering, Fuzhou Univ., 350002, Fozhou, China.
4President, SDR Engineering Inc., 2434 Oakdale St., Tallahassee, FL 32312.
(Accepted 30 April 2003)

Based on data collected by weigh-in-motion (WIM) measurements, truck traffic is synthesized by type and loading condition. Three-dimensional nonlinear models for the trucks with significant counts are developed from the measured data. Six simply supported multigirder steel bridges with spans ranging from 10.67 m (35 ft) to 42.67 m (140 ft) are analyzed using the proposed method. Road surface roughness is generated as transversely correlated random processes using the autoregressive and moving average model. The dynamic impact factor is taken as the average of 20 simulations of good road roughness. Live-load spectra are obtained by combining static responses with the calculated impact factors. A case study of the normal traffic from a specific site on the interstate highway I-75 is illustrated. Static loading of the heaviest in each truck type is compared with that of the American Association of State Highway and Transportation Officials standard design truck HS20-44. Several important trucks causing fatigue damage are found.
In addition - this bridge apparently was a "non standard" design. The road bed was not structural -

Gonna be a while sorting this out I think.
 

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Those trucks are enormously heavy. Given it was rush hour and stop and go traffic one wonders if that was the "straw" that broke the bridge.

That concentrated weight may well have not triggered anything if it was moving quickly but if stopped or moving slowly over a weak point.....

Those trucks get into the 80 ton range.

Clearly it's a problem nationwide
Bridges are designed to allow heavy loads and to allow for heavy traffic. On top of that, there is also a Factor of Safety (not the correct term nowadays) to allow for extreme limits.

It seems reasonable that such a load may be the 'straw', but that doesn't make it the source of the problem, which will be structural in nature and likely related to steel failure.

I'm not sure this is a BIG problem. There are 10's of thousands of bridges in North America. How many fail per year? Less than 1?
 

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Bridges are designed to allow heavy loads and to allow for heavy traffic. On top of that, there is also a Factor of Safety (not the correct term nowadays) to allow for extreme limits.

It seems reasonable that such a load may be the 'straw', but that doesn't make it the source of the problem, which will be structural in nature and likely related to steel failure.

I'm not sure this is a BIG problem. There are 10's of thousands of bridges in North America. How many fail per year? Less than 1?
List of bridge disasters - Wikipedia, the free encyclopedia
 

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When Hanna-Barbera’s cartoon hit “The Jetsons” first aired in September 1962, the interstate decade was in full swing with more than a quarter of the new interstates already built. President Eisenhower’s vision of an immaculate interconnected superhighway system was becoming a reality, and pop culture was beginning to look ahead to a time when we would fly our cars to our offices in the sky and fold up our vehicles to the size of a briefcase.

This year marks the interstate system’s 50th anniversary, just as the U.S. population hits the 300 million mark. With infrastructure aging on a system that was never designed to carry the heavy traffic loads it does today, and funding that is about to run dry, a realistic look ahead to the future of transportation in the U.S. could be very bleak if something is not done about it soon.




All about the money

Since the interstate system began construction in the mid-1950s, vehicle-miles traveled on highways has increased five times from 600 billion to 3 trillion. Although last year’s passage of SAFETEA-LU allotted nearly $300 billion for surface transportation, it is not enough money to maintain all current roadway projects and to begin constructing new projects that would expand lane capacity and provide congestion relief.

Funding from SAFETEA-LU will likely run out by 2008, which is short of the 2009 reauthorization, according to Harold Worrall, president of Transportation Innovations Inc. With funding falling short and the possibility of reauthorization being delayed by a year or two, the U.S. will most likely have to face two or three years without any money to fund our transportation systems.

“There’s a shock about to occur on top of the desperate condition of the roadways,” Worrall told Roads & Bridges. “I just hope that’s going to shock the federal and state officials and electorates to understand that we have to start putting some serious bucks into transportation.”



Growing threats

With the lack of funding and rapidly increasing levels of congestion, the road conditions are quickly deteriorating. The average traveler in the U.S. today spends 48 hours per year in traffic delays. Based on current trends, by the time the U.S. population is projected to reach 400 million in 2043, the average motorist can expect to spend 160 hours each year in traffic delays, a recent American Road & Transportation Builders Association study showed.

Congestion will continue to grow and the infrastructure will continue to buckle beneath it. With much of the interstates having been first constructed during the 1950s and ’60s, many of these roadways are already reaching their design lives. If they are not repaired in the near future, “it’s not going to be a case of minor resurfacing and repair; it’s going to be a case of reconstruct and repair and that’s big dollars,” Worrall said. “If we let it go too far, it’s going to be near unrecoverable. I’m surprised that more policy people are not more aware of it.”

If the transportation industry is going to get the funding it needs to maintain a system that works, it is going to have to have more support from elected officials and the general public in the future.

“Each elected official only finds the right issue to get re-elected again,” said Worrall. “The election cycle is so much shorter than is the cycle for infrastructure development that [politicians] never just bite the bullet because it’s not in their best interest to do so.”

The interstate system was designed to move goods and people throughout the country, but if the system is crumbling, congestion time is growing and government funding is lacking, goods will not be moved as fast as they need to in order to support our economy. “Our surface transportation system drives this economy,” McKee said.

A recent Department of Transportation statistic shows that 87% of all the value of the freight in the U.S. moves on a rubber tire. “For example,” said Worrall, “if we take the interstates away tomorrow, 87% of the value of economic goods in the U.S. would not move.
http://www.roadsbridges.com/What-the-Future-May-Hold-article7517

Assuming the facts in this article are true, it makes me wonder about how much care is going into Canada's infrastructure systems.
 

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Discussion Starter · #13 · (Edited)
Of course it's not the "cause" the truck just MIGHT be the trigger tho.

Most of these are cumulative in some manner, maybe a risky one off design, hotter weather, ( one engineer mentioned this ) a rough road with an outer envelope weight truck, some accumulated stress weakening the steel and little support from the road bed which was being replaced.

In some sense that it's an"unusual" design at least gives some reassurance - unlike in Quebec where there are dozens of cookie cutter over passes of similar design.

Over time tho replacing the Interstate, even just the bridges alone, is going to be one hell of a amount of money needing to be spent. :eek:


This is the photo that caught my eye.

That truck buried.


•••

Beej - can't see a relation with oil exploration technology but perhaps with other imaging technologies for stress and weld issues.
Some of the infrared monitoring over time might have some play.
 

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Are advances in technologies to explore geology, such as for oil and gas exploration, helpful in finding these problems earlier?
We don't know what the problem is yet, so it is hard to say whether it could have been detected ahead of time. If it was a design error, then such imagining technology isn't going to find it. If there was a fracture or a defect in part of the bridge, then perhaps it could have been found.

The technology definitely overlaps into other fields. MRI and CAT scan machines share a lot in common with oil exploration, except they have the benefit of looking in 3D, while geologists are stuck in 2D. I am not familiar on how often structural engineers use such remote sensing technology.
 

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Soon to be followed by numerous lawsuits, and an ABC Movie Of The Week. :ptptptptp

CNN has a little video of the collapse on the front page at the moment. Loads slowly, probably it's being viewed a lot at the moment. Truly scary.
Saw the video. It was really scary how fast it collapsed. And, yes, lawsuits are probably already being drawn up.
 

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What the Future May Hold

Assuming the facts in this article are true, it makes me wonder about how much care is going into Canada's infrastructure systems.
I suspect a lot of it is true. Governments in North America spent a lot of money creating infrastructure in the late 50s and in the 60s but seemed to have followed up with less money to maintain it. Also I wonder how much of it was designed to carry the loads and traffic that they do today. It was mentioned, in connection to the de la Concorde overpass tragedy in Quebec, that the overall weight of trucks is significantly heavier than it was 40 years ago.
 

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If you notice, number 8 on that list is the "Quebec Bridge". The collapse of that bridge killed 75 construction workers and was the inspiration for the Iron Ring that Canadian engineers wear on the pinky of their working hand. Legend is that the steel from the bridge was used to make the first Iron Rings, and the point of the Ring is to remind us of the burden of responsibility that we bear in safeguarding the public.

According to a civil engineering professor interviewed on CNN, there were 500 bridge failures in the US in the 1990's. Most were relatively minor, but he said that half were related to erosion of the bridge pilings due to currents in the surrounding water. It will be interesting to see if that was a factor here.

We must also remember that there is usually a chain of events that leads up to a disaster. It is the combination of many factors that causes bridges to collapse, planes to crash, etc. We can only hope that these peoples' deaths lead to a better understanding of these factors and more advanced designs and construction methods.
 

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Discussion Starter · #19 · (Edited)
I used to recall travelling in Quebec and the main roads were awful due to over weight trucks. I think that has changed.

Look at this :eek:

Minnesota Governor Vetoes Transportation Bill

27 February 2006 - 7:00am

"Literally wielding a big red VETO stamp to appease the no-tax crowd that remains hell-bent on a something-for-nothing relationship with government, Gov. Tim Pawlenty deep-sixed the bipartisan transportation bill. 'How dumb can they be?' he sneered of the lawmakers who dared approve a tax hike to fix the state's roads.
Bipartisan bill too.........fur gonna fly now.....Mike Harris admirers et al..take note....TANSTAAFL

•••

The bridge had been inspected by the Minnesota Department of Transportation in 2005 and 2006 and no immediate structural problems were noted, Governor Tim Pawlenty said late Wednesday. A federal database, however, showed the 40-year-old bridge had been rated as “structurally deficient” in 2005 and possibly in need of replacement, the Star Tribune reported citing the U.S. Department of Transportation's National Bridge Inventory.

The White House also confirmed the 2005 inspection. White House press secretary Tony Snow said the span rated 50 on a scale of 120 for structural stability.

“This doesn't mean there was a risk of failure, but if an inspection report identifies deficiencies, the state is responsible for taking corrective actions,” he said.


Jeanne Aamodt, a spokeswoman for the Minnesota Department of Transportation, said her agency was aware of the 2005 assessment. She noted that many other bridges around the country carry the same designation and declined to say what the agency had done to address the deficiencies.
Shall we blame the terrorists for this - after all .....................fill in the blanks. :rolleyes:

The Cost of Iraq War calculator is set to reach $456 billion September 30, 2007, the end of fiscal year 2007.
 

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