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Baltimore's Key Bridge struck by cargo ship, collapses

wbaltv.com

241–250 of 1001 posts

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#241
post #167

Earlier quoted context omitted.

Because bridges over harbors are quite common an incidents like this are rare.

The Dutch ports of both Amsterdam and Rotterdam have no bridges at all. It's all tunnels. I think that's the best way to go; the least chance of conflict between road and water traffic.

Tunnels can have other issues: https://en.m.wikipedia.org/wiki/Category:Tunnel_fires and given American drivers I think I’ll take my chances with the big old boats.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#242
post #208
post #187

Earlier quoted context omitted.

Bridges only last for roughly 50 years. Considering such collisions are rare enough to make the news as a memorable event you can workout for yourself that the odds are quite low over a bridges lifespan. They are designed to withstand smaller boat impacts because they occur relatively frequently, but cost vs benefit on rare events that are difficult to mitigate is quite different.

Interested in this claim, because it sounds about right, except that I can’t name a bridge constructed in the past 50 years. The bridges we can all name are pushing 100+ right?

How many bridges, such as highway overpasses, that you use regularly can you name?

Here's an interesting list of major bridges with dates, most of the newer ones being replacements: https://www.carolinadesigns.com/obx-guide/fun-info/bridges/

They even note a rare exception designed to last 100 years with maintenance.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#243

Also important to note. The logistic company running this ship was Maersk. That is the same shipping company that had the ever given stuck in the suez canal a few years ago. Is Maersk now officially the "Boeing" of shipping?

What? No it wasn't.

https://en.wikipedia.org/wiki/MV_Dali_(2015)

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#244

Didn’t waterway authorities (in the U.S.) used to require tugs to navigate large ships under bridges?

I thought that they had a pilot board and navigate into port, but I only know of anecdotes.

We'll be hearing a lot more about this. It's a really major accident.

I used to live in Bawldamer, in the early 1980s. Back then, it was a tough, blue-collar city, but not yet The Wire.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#245

Somehow I find it surprising how completely the bridge collapsed after the damage. I understand that a container ship collision is serious, but you could imagine a scenarios where the bridge slumps or buckles but doesn’t just disintegrate like that. It’s surprising that ships capable of doing this damage were probably regularly driving past it, and its safety as a thoroughfare depended entirely on those collisions no…

At least in the links with the video now you can see that the container ship directly hits one of the two main (and in the central area only) pillars completely collapsing it. No matter(1) the engineering there is no pretty much way to not lose the whole large middle area and left area leading to the destroyed pillar in that situation. Such a collapse crates so much force (tension vibrations etc.) so that the collaps…

It certainly does not seem reasonable to design a bridge pillar to withstand a direct impact from a massive cargo ship.

But I guess I thought that maybe there was... typically some kind of earthen buffer around the pillar to prevent such an impact?

That's probably impractical too, I guess.

I guess I just didn't realize ~$1bn bridges were one fluky ship accident away from total collapse at any given time. I think maybe I prefer my previous state of ignorance, to be quite honest....

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#247
post #136

Not that it matters to anyone else, but having driven across that bridge dozens of times with my kids, this is just shocking. It’s one of the main corridors in the area. Thank god it happened in the middle of the night, though that’ll be no consolation to the families of those who may have died.

Local to the area. This was devastating news to wake up to. I don't know what's wrong with me but seeing this and knowing there were casualties made me cry. Edit: Maybe I'm just tired and need more sleep.

There’s nothing wrong with you. It’s okay to sit with these feelings.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#248

Somehow I find it surprising how completely the bridge collapsed after the damage. I understand that a container ship collision is serious, but you could imagine a scenarios where the bridge slumps or buckles but doesn’t just disintegrate like that. It’s surprising that ships capable of doing this damage were probably regularly driving past it, and its safety as a thoroughfare depended entirely on those collisions no…

I did hear one expert on the news say that a better, low-tech defense some bridges have is sacrificial piers in front of the actual ones. I don't know if this bridge had none, or if they didn't get the job done.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#249

Somehow I find it surprising how completely the bridge collapsed after the damage. I understand that a container ship collision is serious, but you could imagine a scenarios where the bridge slumps or buckles but doesn’t just disintegrate like that. It’s surprising that ships capable of doing this damage were probably regularly driving past it, and its safety as a thoroughfare depended entirely on those collisions no…

At least in the links with the video now you can see that the container ship directly hits one of the two main (and in the central area only) pillars completely collapsing it. No matter(1) the engineering there is no pretty much way to not lose the whole large middle area and left area leading to the destroyed pillar in that situation. Such a collapse crates so much force (tension vibrations etc.) so that the collaps…

> So that wasn't a "slow moving" impact

Exactly. It is only the scale and the viewing angle that makes it seem slow moving.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#250
post #211
post #187

Earlier quoted context omitted.

Bridges only last for roughly 50 years. Considering such collisions are rare enough to make the news as a memorable event you can workout for yourself that the odds are quite low over a bridges lifespan. They are designed to withstand smaller boat impacts because they occur relatively frequently, but cost vs benefit on rare events that are difficult to mitigate is quite different.

Doesn't the US have a problem with bridges exceeding their expected service lives?

The boom of bridges after automobiles became common are all running out of time. Yet, paying for a replacement early is also wasteful.

So it's an issue, but those bridges where also constructed by a far poorer nation so it's not that big a deal.

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