Baltimore Bridge collapse after ship collision 125

[Tomfh]

https://amp.9news.com.au/article/b73620ea-64ab-4253-8cb0-37102418fcab

 

[LittleInch]

Gents,

Please reflect on your posts just above and consider deleting them as being off topic and turning a serious engineering thread into a political one.

Thank you.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MTNClimber]

Perfect time to make the Bmore Bridge Thread Part II.

 

[KevinK2]

I can get approximates location from videos online but does anybody have the AIS data the videos were based on?

I have looked for that data for a while now, with no success. But based on the various data plots, it looks like 3 points define the departure from a strait path and final contact with the bridge. Graphically, the first angle is about 5-6 degrees, and the final pair ~12 degrees, as if the ship had a constant force causing it's lateral displacement. I doubt the rudder was in play, as it needs the rush of water caused by the prop to be effective.

One source stated the ship's power was lost .6 naudical miles (.7 miles) from the bridge.

Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

 

[KevinK2]

Recent Video Update, taken from the water:

https://www.youtube.com/watch?v=Pt9lvf4FnZE

Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

 

[FacEngrPE]

I doubt codes/regulations/standards will move fast enough to incorporate those changes, but it is coming.

Only "code thing" that needs to change to address rising water levels is the FEMA Flood Map Program. Which is implemented by local ordinances. Most of what needs to change is the way flood occurrence elevations are calculated in areas subject to sea level rise.

A frequent requirement is that by ordnance the minimum build elevation is defined as the 100 year occurrence elevation + 1 foot. Amy thing below that elevation must be flood tolerant. This makes trouble for designing waterfront facilities (piers, etc).

 

[Alistair_Heaton]

https://maritime-executive.com/arti...an-refloating-sequence-for-containership-dali

Seems things are progressing well.

 

[LittleInch]

From that article think there's a decimal point error....

"Governor Moore reported that each of the laden containers weighs between 1.5 and 2.5 tons [SIC]"

Empty containers weigh that much, not loaded ones, but empty containers going back to the far east are more probable

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[waross]

Empty containers weigh that much, not loaded ones, but empty containers going back to the far east are more probable

Agreed.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[JohnRBaker]

An update, of sorts:

Baltimore bridge deaths: 5th body recovered from collapse site; 1 remains missing

After the discovery on Wednesday, one of the victims' bodies was still missing.

https://6abc.com/baltimore-bridge-d...ple-died-in-the-collapse-death-toll/14754427/

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Alistair_Heaton]

Just reading rebuild to take 4 years and the best part of 2 billion.

 

[TugboatEng]

...until some politician decides they need a monument and orders a suspension section be incorporated.

 

[JohnRBaker]

Well, at least an historical marker...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Alistair_Heaton]

Is the 2 billion realistic?

 

[Murph 9000]

$2 billion sounds plausible to me. According to Wikipedia, the old bridge was 2632m in length, with 56m clearance over the channel. The Queensferry Crossing, a triple-towered cable-stayed bridge over the River Forth in Scotland, is similar in scale at 2700m in length and 60m clearance. It was constructed between 2011 and 2017 at a cost of £1.35 billion.

 

[FacEngrPE]

Point of reference, a current project under construction HRBT Expansion Project
This project will widen the current four-lane segments along nearly ten miles of the I-64 corridor in Norfolk and Hampton, with new twin tunnels across the harbor. The two new tunnels will be approximately be 8,000 feet (2438m) in length.

Including the construction contract and owner’s costs, the project’s total budget is over $3.9 billion.

So replacement of Key Bridge concept cost of $2 Billion is plausible (my opinion) providing the 20 miles of I-695 that constitute the approaches do not need work to increase capacity. I think early estimates are always low due to the complete scope (including politically charged scope growth) not being known.

Historical markers can get expensive

 

[KevinK2]

~Latest Update Video

https://www.youtube.com/watch?v=Z2rToCpwAhc

The massive truss section straddling the front of the Dali, had to be cut in two before removal. Being in a stressed condition required dedicatied cutting methods. I read that "precission cutting" was used, and "simultanious cuts" suggesting explosive charges at the several critical members. Could not find more about how it was done. Anyone know ??

Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

 

[phamENG]

HRBT Expansion Project

Drove over this tonight. First time on the new east bound approach to the tunnel. It's so much taller than the old bridge. Angle into the tunnel is a lot better - fewer people slamming on their brakes for not apparent reason.

For a little more context regarding the HRBT expansion - RFP went out in 2018. Completion just got pushed out another year and a half to late 2027. So while $2B may be plausible for the Key bridge replacement, 4 years may not be.

 

[Alistair_Heaton]

as the Forth bridges have been mention.

Risk analysis of a similar event.

 

[KevinK2]

Precision explosives will soon be used to safely remove the stressed bridge structure straddling the Dali bow:

graphical-representation-precision-cutting-charges-will-used-key-bridge-section


Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

 

[drawoh]

Alistair_Heaton,

I have that bridge programmed into my flight simulator, with a Seafire[ ]FIII. Whenever I feel like trying a flight simulator challenge, I try to reproduce Eric Brown's five loops around that red bridge. The bridge seems to survive this fine.

--
JHG