US Coast Guard shuts part of lower Mississippi River as bridge crack
More than 400 barges were delayed on the lower Mississippi River on Wednesday after a bridge crack prompted the U.S. Coast Guard to halt vessel traffic on a portion of the waterway crucial for shipping crops to export markets.
The Coast Guard stopped all traffic on the Mississippi River near Memphis – between mile markers 736 and 737 – after a crack was discovered in the Hernando de Soto Bridge that spans the river, according to a statement.
There were 12 vessels with 157 barges in the queue to pass northbound and 16 vessels with 254 barges in the queue to go southbound, Lieutenant Mark Pipkin, a Coast Guard spokesman, told Reuters. The barges are carrying a mix of materials including crude oil and dry cargo like corn or rocks, he said.
The bridge carries I-40 over the Mississippi River from Memphis, Tennessee, to West Memphis, Arkansas.
Almost all grain barges must pass underneath the bridge on their way to Gulf of Mexico export facilities near New Orleans after being loaded along the upper Mississippi, Ohio, Illinois or Missouri rivers, according to the Soy Transportation Coalition, an agricultural industry group.
“It is reasonable to assume hundreds of barges of U.S. grain will be negatively impacted by the closure depending on its duration.”
It is not an exaggeration to say this is the American Midwestern equivalent of the shutdown of the Suez Canal.
You haven’t hear a peep about this from the Biden Administration because it’s affecting Midwestern farmers in flyover county.
Also, a bridge over the Mississippi River on one of America’s primary interstates that also crosses America’s primary inland navigable waterways is not infrastructure compared to universal daycare or some other welfare program.
Being the cynical fucker that I am, the governors of Tennessee and Arkansas should issue a joint EO renaming the bridge the “Black Lives Matter and BIPOC PRIDE bridge” to get Biden to rush in and repair it.
This nation is really being run by people who hate it and want to see it fall apart.
That puts all that grain at serious risk from these guys:
https://youtu.be/8G_L9tXEwmc
That I-40 bridge is going to be closed for months. The inspectors actually panicked when they saw it and called 911 to have the bridge shut down immediately.
The *other* interstate bridge in Memphis has no exits for several miles on the Arkansas side and is smaller than the I40 one. It’s already adding 20-30 minutes to transit times between Arkansas and Tennessee.
When Emergency Management war-games a repeat of the 1812 New Madrid Earthquake, their worst-case scenario includes losing both of those bridges.
In a repeat of the New Madrid, losing both of those bridges is part of a best-case. That quake rang bells in Virginia.
Putting on my black/deplorable insurgent hat for a moment. If the bridge were to destroyed in place and dropped into the Mississippi river, how long would it take to clear? How much explosives, or chemical/gas tanker trucks would it require? Which bridges, highway overpass, interstate interchange are most vulnerable or carry the most traffic?
Added bonus, think about persistent industrial waste chemicals (e.g. dioxins, PCBs, PFAS, etc.). Imagine the shitstorm that would ensue if a 55 gallon drum was “accidentally” released into a reservoir for a major city.
“Why y’all booing? I’m right.”
I wonder why they don’t just send a couple of floating cranes to that bridge, to hold it up at each side of the crack.
Then again, I wonder why they don’t just close one channel. It’s a two span bridge, with one of the two spans broken. If the other is intact, as it appears to be from reporting, why on earth would the Engineers close the whole river? Even by their standards of incompetence that’s astounding.
Real reason is that they don’t know how badly damaged the bridge actually is.
In another blog they have a picture of the crack. It is huge. And it has been there for some time. And during that time huge dynamic loads have been moving across that bridge. Those loads were supported which means that stress was moved to other bridge support members,
Some of that stress transfers to the span.
So you have a huge structural member that has failed. You know that other structural members have had increased stress and you have to assume that they were damaged as well.
It could be that they have stress fractures in other structural members that could fail at any moment and drop that bridge into the water and if that happens, the other span is likely to drop as well.
I wouldn’t walk across that bridge right now much less go under it. The men that do the first inspections of that bridge are going to need balls of brass the size of cannon balls.
Then maybe the right answer is to lift the spans out of there with floating cranes and set them to the side.
Must be a bridge built by the lowest bidder, who then cheaped out during construction. Company is probably defunct by now … no one to prosecute…
Bridges wear out.
Metal fatigues.
Just ask J.kb. Be very, very glad this bridge was designed with structural redundancy. The huge freaking structural beam is BROKEN!!! But the bridge didn’t fall!
The I35W bridge in Minneapolis had a single too thin gusset plate fail, and the entire freaking bridge collapsed because the design had lots of single failure points. If the designers had used two (2″) inch thick gusset plates instead of 1-1/2 inch plates on the I35W bridge, it would still be standing today.
“The I-35W bridge was designed and built before metal fatigue cracking
in bridges was a well-understood phenomenon. In the late 1970s, when a
better understanding of metal fatigue cracking was established within the
industry, deck truss bridges such as the I-35W bridge were recognized as being
“non-load-path-redundant”—that is, if certain main truss members (termed
“fracture-critical”) failed, the bridge would collapse. According to Federal Highway
Administration (FHWA) 2007 data, of the 600,000 bridges in the National Bridge
Inventory, 19,273 are considered non-load-path-redundant. About 465 bridges
within the inventory have a main span that is a steel deck truss.”
https://www.dot.state.mn.us/i35wbridge/pdf/ntsb-report.pdf
I thought fatigue cracking was understood way back in the 1950s, thanks to the Comet crashes.
We are still learning every day. Back when they designed the Comet, they thought the engineers in the 1930’s and 1940’s had already solved it all.
The nuclear industry has spent billions learning about and preventing failure mechanisms like stress corrosion, thermal fatigue and the like. Thanks to the elimination of lead solder, now we deal with tin whiskers messing up circuit boards.
I imagine it is a billion times worse in a cutting edge industry like chip fabrication and defense industries.