Container Ship strikes and collapses Baltimore's Francis Scott Key Bridge

jis said:

See the following post upthread...

https://www.amtraktrains.com/thread...is-scott-key-bridge.87125/page-3#post-1037350

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thanks that makes sense.....

As has already been said, I see no need nor reason to increase the span width or height opening. Either, particularly vertical clearance would require far more work than simply replacing the existing structure. I also doubt that there is any foundation damage to the pier that was struck. In fact, the easiest and simplest would be to replace the steelwork "in kind". As to the piers, the above water portion of the destroyed pier should be replaced with a much stouter solid structure, and while at it, replace/reinforce the pier under the other end of the main span to be similar. The type framing in the existing main span piers I would regard as having insufficient strength against impact compared to any bridge over the Lower Mississippi built from the first one that opened in 1892. The major need is a much larger solid surround of these main piers plus two or three very stout dolphins both upstream and downstream of this main span. While at it, place dolphins upstream and downstream of several of the approach span piers. The larger surround (there is probably a proper name for this, but I don't know it) of the main piers should be designed to take a strike of a ship some 50% larger than the current ships at 8 to 10 knots. A ship speed limit should be imposed.

Another ship looses power coming out of the NY harbor. This IMO is no a hapenstance. The whole ship's power situation for all vessels needs rethinking. Why lost power we can only suspect.

https://www.msn.com/en-us/news/us/h...S&cvid=7a98f9c6722f4914b95e170b9cd6739a&ei=37

Bridge Demolition May 13, 2024

Drone view:


Water View:

seems on odd way to demolish the bridge to me. It means the debris is now on the river bed where it will in future be a hazard to dredgers and may one day cost many times what was saved here to lift back to the surface. A severe case of "not my department" mentality.

cirdan said:

seems on odd way to demolish the bridge to me. It means the debris is now on the river bed where it will in future be a hazard to dredgers and may one day cost many times what was saved here to lift back to the surface. A severe case of "not my department" mentality.

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I think it was designed to break up into pieces large enough for the cranes to pick them up, and they're going to clear the debris as soon as they get the ship out of the way and back to the dock.

If you examine the pictures closely you will notice that the ship is down at the bow. there appears to be a lot of concrete on the bow that will need to be removed to float the ship. That removal will be difficult. Do the salvagers just break up concrete with pieces falling into the channel or try to pick big pieces up? Have no idea.

west point said:

If you examine the pictures closely you will notice that the ship is down at the bow. there appears to be a lot of concrete on the bow that will need to be removed to float the ship. That removal will be difficult. Do the salvagers just break up concrete with pieces falling into the channel or try to pick big pieces up? Have no idea.

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The bow down is explained in this video:

west point said:

If you examine the pictures closely you will notice that the ship is down at the bow. there appears to be a lot of concrete on the bow that will need to be removed to float the ship. That removal will be difficult. Do the salvagers just break up concrete with pieces falling into the channel or try to pick big pieces up? Have no idea.

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Is it grounded on the bow but floating on the stern?

Relax none of the exploded debris will be left in the harbor/channel - - -
It was reduced to manageable pieces and parts for easy removal and perhaps salvage - - -
As for the concrete - none of that material was in the center of the navigable channel -
it was the pier support for the metal bridge framework that the ship plowed into -
The bridge framework appears to have been precisely exploded away from the bow of the ship
and into open water -
What little framework remains on the bow of the ship will be plucked away by crane -
What will be a concern is if there is damage to the bow of the ship below the water line thus
maybe causing sinking in place perhaps blocking a portion of the channel for a short period of time
The ship with no floating issues can be towed back to the container port to determine the disposition
of the container cargo and with repair be return to service

I am sure the engineers have all their thought processes tinker toys and lego blocks well in order
designing the replacement and building same as soon as possible
Don't underestimate the resolve of American labor and skills to do this promptly - - -
Look to the legacy of Pearl Harbor and New York 9/11 just a couple of examples !

Removal is sort of like jackstraws, the kid's game. Lots of unstable intermixed pieces. Armchair engineers may never have played the game. Seems to me there's not much sense in building a new bridge to 60 year old specs..better to assess what the need in 2024 may be.

The proposal for building a cable stayed bridge as a replacement has much merit. By placing the support columns way back in shallow water appears a good protection from a repeat incident. But still some protection from runaway barges will be needed. AS well construction will be faster than a standard truss bridge. I do hope that ship owners and operators are held fully liable for all costs but suspect. If so, that will probably mean a bankruptcy will be the result.

Have no idea if any columns of remaining bridge will be useable as each column will need extensive surveys to find any hidden damage. Aswell, the higher clearances proposed for the cable stay may preclude using of the old bridge piers.

west point said:

The proposal for building a cable stayed bridge as a replacement has much merit. By placing the support columns way back in shallow water appears a good protection from a repeat incident. But still some protection from runaway barges will be needed. AS well construction will be faster than a standard truss bridge. I do hope that ship owners and operators are held fully liable for all costs but suspect. If so, that will probably mean a bankruptcy will be the result.

Have no idea if any columns of remaining bridge will be useable as each column will need extensive surveys to find any hidden damage. Aswell, the higher clearances proposed for the cable stay may preclude using of the old bridge piers.

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This requires a full engineering analysis, not educated (or uneducated) guesses. My uneducated guesses are that a cable-stayed bridge has the road surface much closer to the bottom of the span at the piers (there is lots of truss between the top of the piers and the road surface) but the truss itself in the middle of the span is much thicker than a cable-stayed bridge*. To keep the same clearance height above the water, the piers would have to be significantly taller, but perhaps not as much as it might appear because what matters is the vertical clearance between the piers, not at the piers. The truss is thinner in the middle of the span, but the thicker part at the piers extends out a significant distance on either side of each pier. The bottom side of a cable-stayed bridge is much closer to flat and level (compared to a truss bridge) between the piers, which would make the clear channel between them much wider at a lower height.

The piers need to be much taller to support the cables, but I suspect the pier columns are much lighter, especially as they are thinner at the top. And the bridge itself would be much lighter, I think. So the existing piers (if undamaged) might be strong enough to serve as the foundation of extended piers for a cable-stayed bridge. As I said, this requires an engineering analysis. (Maybe an experience bridge engineer could look at the specs and requirements and say in a very short time, "yes - no problem", "no way", or "maybe". I suspect "maybe" would be the most likely answer.)

Perhaps the answer is yes, but it would still be cheaper to build new piers for a different type of bridge. More analysis.

I think a cable-stayed bridge or a traditional suspension bridge could have much longer span placing the piers in shallow water or even on dry land, where they would be safe from boat collisions. Is this sufficient reason for abandoning the existing piers, even if they could be repaired or don't actually require any repairs?

Maybe the requirements have changed and just rebuilding the bridge as it was wouldn't really be the right thing to do. Does it need to be taller, or is it taller than it needs to be? Is it sufficiently wide (enough traffic lanes), or should it be wider? Or narrower? Are the piers fine, but of limited lifetime, so the whole bridge would still have to be replaced in the not-too-distant future?

Finally of course, the ultimate question: "Does Governor Le Petomane have a cousin in the concrete or steel fabrication business?"

[*] I'm worried that I'm not describing what I am picturing here very clearly. The truss of the center span of the bridge (the part that sits on top of the piers) is much thicker than a cable-stay bridge, but the thick part is at the piers, and the center of the span (which is where the ships need clearance) is a lot higher than the base of the truss at the piers. The unobstructed span of the cable-stayed bridge is almost the entire space between the piers, whereas for a truss bridge, the truss obstructs about 1/3 of the span at each end, so only the middle third is unobstructed.

A picture describes the architecture in best terms - - -

Are you picturing something like the Sunshine Skyway bridge - Tampa/St. Pete FL LINK:

https://www.google.com/maps/@27.637...pitch=0&thumbfov=100!7i16384!8i8192?entry=ttu

Zooom in for more detail

WWW said:

A picture describes the architecture in best terms - - -

Are you picturing something like the Sunshine Skyway bridge - Tampa/St. Pete FL LINK:

https://www.google.com/maps/@27.6373805,-82.6993001,3a,17.1y,109.14h,90.68t/data=!3m7!1e1!3m5!1syBFq4gelKSpZm1gzAPKuXw!2e0!6shttps://streetviewpixels-pa.googleapis.com/v1/thumbnail?panoid=yBFq4gelKSpZm1gzAPKuXw&cb_client=search.revgeo_and_fetch.gps&w=96&h=64&yaw=306.31946&pitch=0&thumbfov=100!7i16384!8i8192?entry=ttu

Zooom in for more detail

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Yes, that is what I was picturing for a cable-stayed bridge.

I think I had some other truss bridge in mind, because looking back at the pictures on the first comment, a lot of the truss structure on the Key bridge (not all of it) was above the road with the road actually hanged from it on cables, so the truss only cut off a fairly small part of the clear area between the piers and below the road.

I probably should have looked at more photos of the actual bridge instead of relying on memory, but I think most of my points about the engineering tradeoffs still apply.

The workers are towing the ship back to harbor tomorrow, Monday. Eventually it will go to Norfolk for repairs if or when seaworthy.

Long before Key Bridge collapse, Baltimore mariners warned of ‘ship strikes’, Washington Post, May 23, 2024.

Clears up the state of the bureaucracy a bit.

• Requiring tug boats past the bridge: would be a decision by the ship captain and the local pilot. Not in the article: both tug captains and pilots typically make over $100K/year, and tugs are expensive in fuel, capital and maintenance. Requiring tugs under the Key would raise the question of why not the next bridge too, the Chesapeake Bay Bridge at Annapolis. Large cruise ships can now navigate harbors unassisted, because they have jets on the side. Likely the pressure is on to cut costs, as ports vigorously compete with each other on the East Coast.
• Bridge protection: no clear responsibility.
• Warning people on the highway bridge: communication goes through several hand-offs. In the case of the Key Bridge, it started with the pilot's apprentice making a cell phone call On the bridge deck, the only worker not to hit the water was an inspector, who ran.

Most of the article is about a joint port committee and its minutes. A retirement-age Capt. Joe Smith and one of the committee heads were concerned, with Smith in particular bringing up protection and communications at almost every meeting. Other people on the committee have claimed before this article, and some after, that they didn't recall the issue of a bridge strike coming up. Most people involved have clammed up, as directed by their bosses, lawyers, or unions, it seems.

The committee had no powers, and, surprisingly, the Coast Guard did not either. We're used to hearing about the Coast Guard when rail bridges are built or rehabbed, where they seem to have strong powers. For example, Brightline in Florida, and the New Jersey situation for the Gateway Project on the NEC.

The ones clamming up will need to be dragged into court or congressional / state committee and be under oath. First question. Who and what were you told to not disclose?
These deadly bridge strikes will keep happening. Better protection of piers from both ships and barges. The intercoastal waterway certainly has a lot of bridges as well. Better inspections of ships to mitigate possibility of power failures may be needed. More training of crews and masters. More and better dolphins. No limits on liability by anyone who strikes a bridge. Quick communication to any bridge owner or operator if bridge hit. Thinking mainly of unmanned bridges such as Sunset collision or the Sunshine bridge strike.

Interesting early view about an actual proposal that has been put together in preparation for joining the bidding process.

west point said:

The proposal for building a cable stayed bridge as a replacement has much merit. By placing the support columns way back in shallow water appears a good protection from a repeat incident. But still some protection from runaway barges will be needed. AS well construction will be faster than a standard truss bridge. I do hope that ship owners and operators are held fully liable for all costs but suspect. If so, that will probably mean a bankruptcy will be the result.

Have no idea if any columns of remaining bridge will be useable as each column will need extensive surveys to find any hidden damage. Aswell, the higher clearances proposed for the cable stay may preclude using of the old bridge piers.

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There's a lot to see at this web site : https://keybridgerebuild.com/

The cable stayed bridge does look like an improvement, and it might not take any longer than other designs.

Thoughts.
It may not be possible to build a new bridge pier at the location where the DALI hit. Would like to see the kinetic energy calculation of that hit. The hit damaged the present pier beyond repair but may have even caused fractures in the bedrock that the pier was anchored to. The farther away from that location the better. However, coring samples will need to be taken to verify that a location of a cable stayed pier has stable bedrock for a pier. Also, a new NE pier as well.

Until coring samples are completed the total pier costs are not know until the depth of the piers underwater are known. + the condition of the bedrock at those locations. Only when pier locations and set can the actual span length be precisely known.

Then there will be some weight difference of new piers compared to the downed bridge. How much more is anyone's guess as probably some what lighter materials can be used.

Then there is design of the key connecting section joining the 2 spans parts together. Weather conditions of planned joining, especially outside air temperature leading up to the joining to compensate for thermal expansion.

tgstubbs1 said:

There's a lot to see at this web site : https://keybridgerebuild.com/

The cable stayed bridge does look like an improvement, and it might not take any longer than other designs.

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Experience elsewhere shows that once all the permits hoops are cleared it could be built in as little as a couple of years.

The detailed design activities carry on in parallel with the permitting activity, the latter could take considerable time in the US running into many years.

Looks like the replacement for the Key Bridge has received Federal environmental approval.

https://patch.com/maryland/pikesvil...al-update&utm_medium=email&utm_campaign=alert

And they say it's all those environmental rules that hold up infrastructure projects.

So it looks like they are making progress on the plans for reconstruction and have awarded a contract. I don't know what particular 'phase' they are talking about but it looks like other construction companies could be involved later.

https://apnews.com/article/francis-...tract-kiewit-b869b0c42fc32579a3f8b98f09b44ff3


"At a monthly meeting Thursday morning, the Maryland Transportation Authority board awarded a $73 million contract for the first phase of the project to Kiewit Infrastructure, which calls itself “one of North America’s largest and most respected engineering and construction organizations.”

Officials have said the new bridge will be somewhat taller than the old one to accommodate ever-larger ships entering Baltimore’s harbor. The original Key Bridge took five years to construct and opened in 1977."

As for the ship itself, it's been cleared of cargo and somewhat repaired in Norfolk and will soon sail to China, presumably for more repairs.

• Arriving in Norfolk with a large escort: https://www.vpm.org/news/2024-06-26...and-francis-scott-key-bridge-collapse-repairs
• Looks strange without the cargo and with temporary repairs: https://www.wtkr.com/transportation...ltimores-key-bridge-has-all-all-cargo-removed
• Legal letter says it's going to China, the Sun says probably for repairs: https://www.yahoo.com/news/dali-ship-knocked-down-key-233500634.html