Posted on 08/08/2007 7:59:09 PM PDT by neverdem
MINNEAPOLIS, Aug. 8 Investigators have found what may be a design flaw in the bridge that collapsed here a week ago, in the steel parts that connect girders, raising safety concerns for other bridges around the country, federal officials said on Wednesday.
The Federal Highway Administration swiftly responded by urging all states to take extra care with how much weight they place on bridges of any design when sending construction crews to work on them. Crews were doing work on the deck of the Interstate 35W bridge here when it gave way, hurling rush-hour traffic into the Mississippi River and killing at least five people.
The National Transportation Safety Boards investigation is months from completion, and officials in Washington said they were still working to confirm the design flaw in the so-called gusset plates and what, if any, role they had in the collapse.
Still, in making public their suspicion about a flaw, the investigators were signaling they considered it a potentially crucial discovery and also a safety concern for other bridges. Gusset plates are used in the construction of many bridges, not just those with a similar design to the one here.
Given the questions being raised by the N.T.S.B., it is vital that states remain mindful of the extra weight construction projects place on bridges, Secretary of Transportation Mary E. Peters said in a statement issued late Wednesday.
Since the collapse, the concern among investigators has focused on fracture critical bridges, which can collapse if even a single part fails. But neither the safety board nor the federal Department of Transportation on Wednesday singled out any particular design of bridge in raising its new concerns about gusset plates and the weight of construction equipment.
Concerns about the plates emerged not from the waters of the Mississippi River...
(Excerpt) Read more at nytimes.com ...
Cool, I have a bridge crew out tearing up a bridge deck at this very moment. Tomorrow at 6 AM, they will finish up their workday, and I'll have 2 more crews working on differnet bridges. Yeah, we have to calc loads, but nothing exceeds the loading of an 80,000 lb. tractor trailer.
Woohoo, now everyone cares about bridges. Looks like I'll have job security until about christmas, when nobody will care any more.
Friday, Laura Bush visited friend on Hennepin avenue before visiting with the MSM at the bridge. /s
I have been reading your work on here before and find it very interesting. Thjank you for your insight. It has helped me to understand this.
From the video I saw, the center section just drops. First one side and soon the other. Once freed from the center section, the shore sections simply fall back on themselves pulling and twisting on the pilings on the shore on each side of the river. 1 of These pilings is only in the river when it is high.
My opinion only.
I think he meant both sides of the roadway, not both ends of the bridge. It did look like both sides failed at the same time, the bridge didn't seem to twist much as it fell.
How could this be? I thought Bush spent all the country's money on the Iraq war and there was none left for "infrastructure". Maybe they were volunteers.
Ah contraire for coal mines are the money grab in real time now.
Explain to me what you think they were doing dumping rock onto the bridge?
They were resurfacing the bridge. That means they were taking off a layer of rock and then removing the broken pieces. The next portion of the job is to lay a new layer of cement.
I can't fully tell exactly where in the center span all the trucks and rock we were discussing was, but IF it was all concentrated toward that south pier -- and the pier was possibly weakened by scouring -- is it plausible to suspect that the excessive weight concentrated in one spot may have placed stress on the pier in just the right angle or something to cause the pier to fail as you suspect -- or even if a gusset plate or a girder failed right there could that create the stress needed to cause the southern pier to shift and fail???
Cement wouldn’t do much, it’s just a fluffy powder. :)
This is an obvious ploy by the Bush administration to foist the blame off on some poor underpaid state engineers. It won't work because everyone knows the administration has final approval of all state bridge designs.
America's lawyers and media would have you believe that every accident is an evil act perpertrated by the people that actually make our society work!!
I couldnt see both shore sides on the security video from the lock. The shore sides of this bridge were quite different. One had an off ramp (extra support) right at the shoreline. One side was higher up than the other.
I forgot to “sarc” it; next time.
The reports the last few days said the crew was jackhammering the concrete away, and then was applying a 2 inch layer of crushed rock that the new roadway would sit on — the reports specifically said 100 tons of crushed rock were on the bridge ready to be spread (or already spread - that point was unclear)
What did design have to do with it? That Gusset plate went when the cruise missile hit!
PSSST!
Don't tell anyone for it's our little secret but President Bush's tax cut's created more revenue than what raising taxes to pay for infrastructure has.
hmm come to think of it — have they completely ruled out the Bridges center fuel tank exploding yet????? ;-)
“Bush was here on saturday to check his work and was seen smirking.”
He’s got his mother’s mug doesn’t he?
You mean MN’s 2.2 billion $ budget surplus this year was real? Sarc/off
I would bet there are thousands of rivited gusset plates in the Empire State Building and every other major building and bridge built before 1965.
I'll know that to be true when I can travel 35W instead of 280 and see a sign showing a cruise missile in a red circle with a line through it just before crossing the bridge.
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