But it’s not just a question of how to patch it up. They surely need a thorough understanding of why it happened before they start remedial work.
Major failure of some sort. Either design or steel. Could impact far more than this crack. This crack will be easy to fix. Just rivet/weld plating around it to give it sufficient strength. If all steel in bridge defective then big bucks for the taxpayers, same if bad design. I’m guessing it will be a billion or two dollars gone because some inspector got a $100 bribe when they were building the thing.
There’s a story describing it as a “fracture, which is less than a quarter of an inch”. I’m not an engineer, but I don’t think a quarter of an inch of air is any stronger than a foot of air.
The AP story also says “months”:
Shutting down a bridge for inspection and repair is nowhere near as disruptive as something like this would be.
I’ll never forget the little girl who called her mother afterwards, after her day care van crashed, crying, “Mommy, the bridge broke when we went over it.”
A collapse in Memphis could potentially be far more disastrous, because the mighty Mississippi is much wider and deeper here than it is in the Twin Cities.
I have not seen that, although I vaguely recall two bridges in Massachusets.
Yes, it’s good we found it before the bridge collapse.
I do wonder how long Mississippi river traffic will be halted as a precautionary measure.
I am an electronic engineer, not mechanical, but I would venture to say that you are correct.
Again, IANAME (I am not a mechanical engineer) but I would think that riviting a splice onto the beam would prevent an unloaded bridge from falling into the river, and while preventing vehicluar traffic, allow river traffic to resume.
Barges are darn big. I have seen several controlled by a single boat on the Arkansas, and on the Mississippi when I used to regularly travel between Memphis and Little Rock.
Here are two that got away from the boat during the 2019 flood of the Arkansas.
Runaway barges on Arkansas River hit dam in Oklahoma, at least one sinks - ABC7 Chicago
Wow…I drove over that bridge heading west yesterday around 10AM, apparently a couple of hours before they discovered the crack. I had been telling myself I dodged a bullet by heading home from the southeast when I did–just before the gas pipeline debacle. Now it seems that my timing crossing the Mississippi was pretty fortunate as well.
And barges hit another I-40 bridge in Oklahoma in 2002.
There may be some that aren’t for monetary reasons etc but all interstate bridges are supposed to be two spans. The system was built for defense and twin bridges make it harder to bomb both even though it is a lot more expensive. Some of the other things for defense are, the width was set so tanks could ride abreast and sections were designated to be used as runways.
I thought the freeways being built to land aircraft was bogus.
Indeed – I’d often heard the “designed to be used as runways” story, but even the Department of Transportation says it’s a myth.
I think all of this is bogus. Cite? There may be other good reasons for twin bridges, but I find it hard to believe that we’d make huge and massively expensive modifications to our civilian infrastructure based on considerations that sound like they would be important only in the far-fetched scenario of a conventional war conducted on U.S. soil. (Although I suppose it’s more plausible that it might have been a design factor mid-20th century.)
Have you heard about the GOP’s new voting laws? How about Trump’s wall? Did you hear about the insurrection on 6 January and about all the people who gathered last state capitols because they were afraid that Antifa was gonna appear and magically take over? Were you not around for Y2K?
Making huge and massively expensive modifications to our civilian infrastructure or just doing massively stupid things with massive numbers of people based on considerations that sound like they would be important only in a far-fetched scenario is like 40% of what the US does right now.
Fair point.
While I don’t know the situation concerning Interstates in other situations where you are upgrading from 2 lanes to 4 lanes and there is an existing 2 lane bridge sometimes another 2 lane bridge is added, instead of tearing the existing bridge down and building a bigger bridge.
Looks like just one to me.