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Surprised there have been no comments about this yet and how it went down like a pack of cards.
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>> Surprised there have been no comments about this yet and how it went down like
>> a pack of cards.
I would think that if the support structure is hit hard by something with momentum and mass it's difficult to see how a bridge of what looked like a cantilever construction would not collapse.
Judging by the reports I've seen/heard the mitigation when a collision risk was present was to throw lights to red/lower barriers. Hence the casualties seem to be limited to workers patching the road surface.
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Does make you think how our bridges would cope with a hit like that?
Up here in Scotland we have the Queensferry Crossing which is relatively new. Would be interesting to see what designs were to try and mitigate something similar.
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The ship AIUI hit the pier. The pier held the bridge up. The pier could not withstand the impact of a 100,000 ton ship, which by all accounts was moving quite fast.
I think there will be recommendations following whatever enquiry is conducted, but I doubt if the bridge will be considered to be the problem. Perhaps they will relate to the maximum speeds allowed to limit kinetic energy.
It's not unusual for there to be structures designed to deflect shipping away from bridge structures but as best I can see from the picture, the ship was heading directly for the pier.
There's also the fact that the bridge was designed 50+ years ago, when 100,000 ton container ships did not exist. The Dali is far from the largest but its capacity exceeds that of any container ship built before the 2000's.
Last edited by: Manatee on Wed 27 Mar 24 at 13:43
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Is Putin blaming Ukraine?
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While not common, it happens a fair bit. There have been 15 bridge failures in the US since 1990 caused by waterborne collision. Not as many as hydraulic (force of water, scour, flooding) -48. The USA has a lot of bridges,
Ok this one was spectacular. Should be mitigated by protecting concrete piers.
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I was surprised that they were operating large ships in a relatively confined space with obstacles without a tug in attendance, but it must be their SOP. Maybe not anymore...
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>> Surprised there have been no comments about this yet and how it went down like
>> a pack of cards.
>>
Any fool can design a bridge that will stand up. It takes an engineer to design a bridge that will only just stand up.
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Interesting things, bridges. Very few if any would take 100,000 tons bashing into them sideways. As Z says, the ones in seaways typically have some separate 'obstacles' to protect the piers.
50 years ago I worked on Kirklees Viaduct on the M62. The decks* and their supporting beams are not actually fastened down, the box beams just sit on bearings on top of the piers and abutments, the decks expand and contract by maybe 3 inches between the cool of night and warmth of the day, taken up by a comb joint at the west end. It's about a quarter of a mile long.
Not much chance of a boat or a train bashing into it. The boats are narrowboats, and the canal, river and railway are about 80 foot below the bridge deck.
*there are really two bridges, one for each carriageway.
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Baltimore bridge collapse - Bromptonaut
