Oops! Sorry! I see that now.
I don’t think this was the issue that caused the bridge to collapse. A HUGE fully loaded container ship hit the bridge and that was going to take it down regardless of anything else.
This is a great article.
I know. That’s the point. But the newspaper wording indicates otherwise.
I’ve started to read things about “fenders” for bridge post. But… I assume they would only be designed for nudging a slightly-off path ship ?
I think a ship that weighs 100 million pounds would plow right through any fender.
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The St. Pete bridge was rebuilt with fenders. Would they STOP a ship? I don’t really think so–all a matter of physics. How big a ship? How fast? Weight?
Just spouting here…
I read that some fenders stop a 4kph ship.
The resting speed is 7 Kph for the cargo ship.
…the math is not adding up even if bridge had fenders…
Honestly it comes down to the electronics on the ship. What happened there?
I read/it was leaked/reported/speculated that the ship had power problems for two days prior.
True/false?
Just gotta wait.
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There is also some speculation that the ship’s fuel was contaminated which lead to loss of power. This was the cause of our local ferry accident recently. Thankfully, no one was seriously injured.
I think they were talking about the more general definition of infrastructure (as in bridges, highways, etc.), rather than the steel and concrete bridge itself.
infrastructure
[ in-fruh-struhk-cher ]
noun
- the fundamental facilities and systems serving a country, city, or area, as transportation and communication systems, power plants, and schools:Investments in infrastructure helped the U.S. economy recover from the Great Depression.
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Caissons or dolphin are not uncommon to help prevent this sort of thing according to a guy talking on the Brian Lehrer show this morning. Whether they can stop a container ship I don’t know, but they might have bought the people on the bridge a little more time. Apparently we don’t have to worry about the NY harbor, because it’s so tight they have the tugs take the boats under all the bridges. Our Maritime and Bridge Infrastructure | The Brian Lehrer Show | WNYC
This article says the ship actually weighed 200 MILLIION POUNDS. I cannot even comprehend the force with which it struck the bridge. When I was a young engineer, I designed a few bridge abutments and had to consider ice loads. I wish I remembered details, but you wouldn’t believe how much force mere floating ice exerts on stationary objects.
https://www.politico.com/news/2024/03/27/baltimore-bridge-cargo-ship-buttigieg-00149307
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I just read this statement by a structural engineer:
"Engineers design structures – and bridges are no exception – for a certain probability of failure, because if we didn’t, the cost would be prohibitive. Theoretically, you could build a structure that would never fail, but you’d have to put infinite money into it. For a critical bridge of this type, we would consider an acceptable chance for failure to be 1 in 10,000 years.
Based on published information, I tried to compute what the probability of this event would be, and it turns out to be 1 in 100,000 years or so. The ship made a beeline directly to the pier that was vulnerable. It was just shocking to see such a rare event unfold."
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Yes, they are to reduce the chance of a colliding ship damaging the bridge.
Below is a photo of the fender on the San Francisco - Oakland Bay Bridge after the Cosco Busan hit it.
The Cosco Busan after the collision:
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This is a photo I took while crossing this bridge last month. It obviously doesn’t do it justice, but watching this ship going under gave me high anxiety.
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And now we know your anxiety had some good (but low odds) reasoning.
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I’m much more anxious about wrong-way drivers. We’ve had a lot of those recently, on the highway I travel on all the time. I would go over many, many bridges before driving on this highway if I could.
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Agreed. Think of the trust you put in the stranger coming at you at 40mph, separated by nothing more than a painted line.
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Those undivided roads can have speed limits and actual speeds significantly higher than 40mph.
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And not everyone follows the speed limit too so you could be looking at 70, 80, 90mph. . .
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" From 1960 to 2015, there were 35 major bridge collapses worldwide due to ship or barge collision, with a total of 342 people killed, according to a 2018 report from the World Association for Waterborne Transport Infrastructure."
" There are nearly 43,000 fatal crashes a year in the U.S."
So 342 deaths WORLDWIDE in bridge collapses in 55 years, versus 43,000 deaths in the US alone each year.
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