Baltimore Bridge

[BananaDunka]

What kind of bridge would be able to withstand a direct hit from a ship that size? How much kinetic energy would the structure have to stop - not just slow down, but instantly stop?

"Our lowest estimate of how much force it would take to slow the Dali, if it were fully loaded, is around 12 million newtons, about a third of the force it took to launch the Saturn V rocket for the Apollo moon missions.

And our higher-end estimates, reviewed by several civil engineering experts, suggest it is realistic to put the force of the impact with the pier at upward of 100 million newtons.

“It’s at a scale of more energy than you can really get your mind around,” said Ben Schafer, a professor of civil and systems engineering at Johns Hopkins."

Force of Ship Impact Was on the Scale of a Rocket Launch

A Times analysis used preliminary data to estimate the force of the impact on the Baltimore bridge. It involved “more energy than you can really get your mind around,” an expert said.

www.nytimes.com

I think the short answer really is not many bridges, old or new lol.

 

[Blackjack Davy]

Which is why according to an expert these days they would build an earth rampart for want of a better word around the bridge support to absorb the energy of the impact before it hit the structure, when it was built the average ship size was around 44,000 tons these days its nearer 300,000 tons, a massive difference in kinetic energy

 

[Dis86]

What kind of bridge would be able to withstand a direct hit from a ship that size? How much kinetic energy would the structure have to stop - not just slow down, but instantly stop?

Jonathan V. Last (@jvlast) on Threads

I've been trying to figure out an f=ma equivalent of the container ship bridge collision to give people a sense of scale. If something weight 93,000 tons is moving at, say, 2mph, and collides to a near-immediate stop, what is kind of event is that like, physics nerds?

www.threads.net

"It’s like getting hit by ~5200 bananas going at Mach 1" lol

Mach1 banana sounds like a good forum name

 

[dowie]

What kind of bridge would be able to withstand a direct hit from a ship that size? How much kinetic energy would the structure have to stop - not just slow down, but instantly stop?
[...]

"It’s like getting hit by ~5200 bananas going at Mach 1" lol

Yup, it's an insane amount of force, as Werewolf pointed out earlier in the thread. That's why they instead aim to deflect ships away from hitting bridges etc.. rather than stopping them.

 

[Scougar]

The amount of trash talking and 'conspiracies' on the Bridge are just ridiculous. Even politicians here suggesting that it was x persons fault etc.

The other thing is the repub's are saying the fed shouldn't assist in paying for the bridge to be replaced. If this had happened in Texas with a major port for example, they would be screaming for this to be done.

This is a major port, and anyone trying to play this for political gain is an idiot. This impacts EVERYONE. I hate politics when it's like this.

 

[DB_SamX]

It does however potentially explain a fair bit about the build quality of his cars

I can't imagine any actual qualified engineer even entertaining the idea unless there was no other option to ever build something else.
Besides anything else that isn't visible to the naked eye, there is going to be a lot of that metal that is bent and is going to be faster to replace than try and fit back together.

I also suspect any replacement is going to be a design that isn't "single point of failure", and will be built to current standards, not the standards of the 1960's.

There is currently a big push in the industry to reuse existing/old steelwork, as long as not damaged. "circular economy". Lots of guides have been published to help engineers assess their capacity, and website to buy/sell old steel. So it wouldn't surprise me to potentially reuse whatever steel ie still intact/decent condition.

What does reuse mean in this context?

Do you mean fishing out the bits truss work giving it an inspection and maybe a protective coat before using it on a new project? Or is there more involved?

I don't know I'm afraid. I haven't really had much opportunity to reuse steel to know its limitations.

 

[Colonel_Klinck]

 

[Sankari]

This is a major port, and anyone trying to play this for political gain is an idiot. This impacts EVERYONE. I hate politics when it's like this.

Welp...

Driving the news: In a statement on laying out its "official position," the Freedom Caucus offered several proposed limits on the funding.

1. That the U.S. seek "maximum liability" from the foreign shipping companies involved in the collision and draw from all available funds.
2. That any federal funding allocated for the bridge be offset – likely with budget cuts – and that all "burdensome regulations," such as the Endangered Species Act, are waived.
3. That the bill be "limited to the physical structure repairs with a federal nexus" and not include funding for any "unrelated projects."
4. That the Biden administration lift its pause on liquefied natural gas (LNG) exports "before Congress considers appropriating any funding for the bridge reconstruction."'

(Source).

 

[Dis86]

Absolute bunch of morons.

 

[Diddums]

ANNAPOLIS, Md. (AP) — Maryland plans to rebuild the Francis Scott Key Bridge in just over four years at an estimated cost between $1.7 billion and $1.9 billion, a state transportation official said Thursday.

Maryland officials release timeline, cost estimate, for rebuilding bridge

ANNAPOLIS, Md. (AP) — Maryland plans to rebuild the Francis Scott Key Bridge in just over four years at an estimated cost between $1.7 billion and $1.9 billion, a state transportation official said Thursday.

apnews.com

Four years and almost 2 billion? Are these the same clowns that had a go at our HS2?

 

[StriderX]

Going by inflation it costs the same as it previous one, though in all likelihood it will cost probably twice as much.

 

[Minusorange]

Maryland officials release timeline, cost estimate, for rebuilding bridge

ANNAPOLIS, Md. (AP) — Maryland plans to rebuild the Francis Scott Key Bridge in just over four years at an estimated cost between $1.7 billion and $1.9 billion, a state transportation official said Thursday.

apnews.com

Four years and almost 2 billion? Are these the same clowns that had a go at our HS2?

Perhaps you should tender your own plan to build it cheaper & faster ?

 

[Werewolf]

Going by inflation it costs the same as it previous one, though in all likelihood it will cost probably twice as much.

One thing to remember, I know it's fun to bash building projects and say "today it'll cost a lot more", whilst that's true much of the time it's because we tend to build with more safety margins and features from the outset and modern safety provisions for workers tends to add to the cost.
IIRC there was a bridge where it was one of the first to have a "safety net" under it during construction, a lot of people were upset about the cost/what it suggested (I think inc some of the construction crews/bosses), right up until it saved the first worker.
Sure you can work a lot faster without a safety harness, which can reduce the time it takes to build, but it also means you're likely to lose skilled personnel. The flip side is modern construction methods tend to be faster and less manpower intensive.

In this case any new bridge is going to have the added cost of additional safety features and "defences" against collisions with ships where possible.

 

[aVdub]

Very cheap and good value when you consider the costs of projects in Afghanistan and Iraq

 

[200sols]

Four years and almost 2 billion? Are these the same clowns that had a go at our HS2?

Large infrastructure projects are not cheap are they? Also America is littered with over budget half finished railway projects so maybe you are right on that front.

 

[Uther]

Half for the bridge , the other half for the corruption.

 

[MadMossy]

Guess I was right about the expected cost, I thought it would be a $1+ billion, and likely double or triple in cost over time, but $2 billion at the start, someone is buying a new super yacht with this deal.

 

[Diddums]

Large infrastructure projects are not cheap are they?

No, but I think in today's world where people talk about billions like it's the new million, people don't actually realise how much money it is. Two billion is two thousand million. That's a lot of cheddar, this bridge could very likely be built for 10% of that!

 

[MadMossy]

£1 million in £20 notes stacked is around 5.65 metres high.

£1 billion in £20 notes is 5650 metres high or about 2/3rds of the height of Everest, at around 3.5 miles.

The bridge cost around $60 million to build in the 1970s. Even with inflation that would only be about $450 million today. So $1.9 billion is insane.

 

[Terminal_Boy]

Price of structural steel is 6-7 times today what is was in the 1970s.