A collapsed portion of the Interstate 35W bridge over the Mississippi River is seen Wednesday, Aug. 1, 2007, in Minneapolis. (AP Photo/Star Tribune, David Denney)
Posted on 08/01/2007 4:28:27 PM PDT by ButThreeLeftsDo
Just turned on the news. 35W bridge collapsed in the Mississippi River. Cars, trucks, semis.....
Fires burning, tanker trucks, at least one school bus, more than ten cars......
Just now breaking.......
NORM!!!!
Structurally vaporized. Mainspan sheared at both ends and drops straight down. You heard it here, first.
Wow, what a pic. That’s just madness.
Salt on decks corrodes rebar in the deck. Drainage systems on bridge decks divert all storm water away from the structural elements. (but it does look like an upper chord failure, at a support bent. The weakest point on a cantilever is over the support bents)
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I heard a witness(FOX) that said he saw it buckle in the “middle.”,,,Maybe thats why it looks like it was pulled down in/from the middle...?
A collapsed portion of the Interstate 35W bridge over the Mississippi River is seen Wednesday, Aug. 1, 2007, in Minneapolis. (AP Photo/Star Tribune, David Denney)
See #1564. There appears to be a great deal of twisting in that section.
No. The organic deicers have no chloride. The reason for using them is to minimize corrosion. The stuff is more expensive and the expense is justified, because it minimies corrosion. The only significant source of chloride would be what was picked up elsewhere and washed off the vehicles passing over the bridge.
Finally a “long” shot. It does seem that the problem started in the twisted section between the piers on the far side of the river.
I dont think it had anything to do with pouring new concrete or having rush hour traffic.
The bridge is most certainly designed to handle a full liveload capacity way more than if the entire bridge was a parking lot.
I bet there were some unidentified cracks in the steel and that the vibration work from removing the concrete top , and scoring new concrete led to a failure of one steel member in a critical location over the river span. The There is very little redundancy in that truss span design. As the main span dropped, it pulled down the spans over land.
Glad to hear you're okay. Our phones were ringing non-stop for awhile, everyone checking on everyone.
My daughter just took another job closer to St. Paul two weeks ago. She had to park and ride and take the bus over that bridge everyday on her old job. Just a horror for those involved.
Take a closer look at the picture!
Yikes, if you can not figure this out, get a beer. Will it tip over to one side if you bump it, or will if squash perfectly flat? Even a drunk knows that a beer will tip over on it's side!
They learned that lesson real quick. That bridge's twin -- the Whitestone Bridge -- was shored up to prevent resonance, and it is a very stable bridge. I've crossed it "billions and billions" of times with nary a second thought. The only bridges that truly gave me the creeps are the ones in the mountains in Pennsylvania, where you look down and feel like you're looking down out the window of an airliner. (And, a wood plank swinging footbridge. *shudder*!)
“The organic deicers have no chloride. The reason for using them is to minimize corrosion.”
Right you are. But, this bridge is 40 years old and organic deicers are relatively new.
I wonder who will be the first one to say that if we weren’t in the war with Iraq, there would be more money for infastructure. Someone will.
My main point is that it is very likely it was a combination of many factors, which when all added together caused the collapse. One factor alone, or two, wouldn’t do it.
Only in the sense that he's deeply in love with the sound of his own voice.
Mainly, he's "metro."
The catastrophic breakup of such a structure, from the point of view of somebody on or near the bridge would sound like an explosion.
Who said anything about bumping anything? Certainly the steel members on one side could fail and the structure would twist toward that side.
Wow, that's crazy. Makes you think of sayings like, "don't sweat the small stuff".
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