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.......
A person with a muslim/arab name was just on Greta theorizing what may have happened. He is an expert on bridges and building trusses who investigates these kind of collapses in the US according to Greta. He used the analogy of a brick arch to explain the collapse. He claims that if you move one brick, the entire structure collapses. No mention of a possible terror attack.
Good work. I shut off sheared gas mains after an earthquake. Others became inspired to do their own good work selflessly after me, as you probably witnessed there. It's the right thing to do to save lives if you are able to.
Thanks. I saw that it had to be a minimum depth of 11 feet, but I’m not an engineer who deals with data like this on a regular basis, so I figured someone else, like yourself, could translate. Thanks again.
What do you think would make a block fail.
freepmail backatcha, Granny
I’m afraid of what I’ll see when I turn on my TV in the morning.
Having fished under where that bridge is in my much younger years I’ll tell you theres a lot of current right there even with the record low levels we have this year. I do a little fishing on the Miss and live on it, the river does whatever it wants, and don’t always tell you about it.
Texas and Arizona don’t experience -20 degree temperatures on an annual basis.
Thanks for your prayers. This just makes me heartsick.
Look at the bridge shoes (lowest visible steel atop the piers) for the main span.
Those four locations support not only the main span, but also half to all (depending on how the cantilever trusses are designed) the weight of both of the next two approach spans, plus any live load (vehicles) those three spans of the bridge are carrying.
That translates to significant (massive) point loads at those locations.
Thank goodness they’re ok.
fyi - Greta just announced live Fox coverage will be all night long
You’re welcome....I can certainly understand your sorrow for the people of your state. I read your earlier post....so thankful that the members of your family are safe.
I pray that no more of the bridge collapses. People will have to stay home from work tomorrow, I would imagine.
Scour is when there is, say, a post structure of some kind in the middle of a river, that supports a bridge. As the river water hydraulic forces work on the riverbed around the base of a support, the water force can eventually "scour" out the riverbed around the support structure, eventually undermining the support. At some point the support column collapses and the whole structure comes down.
There have been several bridge collapses from this effect, HOWEVER... this particular bridge does not appear to have had any supports that were actually in the river. There were concrete caisson type supports on either bank but the bridge spanned the entire river with nothing subject to scouring.
So, there's that.
I join in urgent prayer for all of these!
Those pilings don't look like they are in the water to you?
Hey Luv.
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