Suez Canal blocked by container ship 36

[verymadmac]

It might not be an engineering issue that started it, but I bet is going to change a few specifications.
BBC piece here Link



It looks like the bow is hard aground, refloating will be an interesting exercise given the time pressure.



Canal profile is here

https://www.suezcanal.gov.eg/English/About/SuezCanal/Pages/CanalCharacteristics.aspx

 

[Alistair_Heaton]

Can't find where I saw that one about the US opposing . It was something to do with panama canal loosing traffic. But could also have been about how they were going to finance it.

Oh remember now it was to do with oil and having two way through it would increase the flow to Europe of LPG from none US sources.

 

[thebard3]

RedSnake--
I believe MT= metric tonne.

Brad Waybright

The more you know, the more you know you don't know.

 

[RedSnake]

Okey so the tugboat ALP GUARD hade a straight pull of 258 tons ?

Best Regards A



“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[TugboatEng]

Yes, we call that a bollard pull. After construction the vessel gets attached to a bollard and pulls for all it's got with a dynamometer installed in the line. Those anchor handling tugs have controllable pitch propeller and big engines so they can make big numbers on their bollard pulls.

 

[waross]

Sticktion or static friction must be overcome.

Waross, if it was strictly inertia, any amount of pull would eventually get it moving so there certainly had to be some stiction involved.

Hence my question about your hammer and several tons of stiction.
In the case of the 'Given, most likely the ship rode up on the rock (Sticktion) and then the weight supported by the rock became more than the bottom could support and the the bottom plates failed.
Then the rock was inserted into the hull and formed a key, or dog.
Neither sticktion nor inertia but a mechanical interlocking.
By the way, swinging the stern would have broken the stiction.
This technique has been known by horse loggers for a couple of hundred years.
When the horse could not start a log moving, the logger would take a side pull to break stiction.
Once the log started to move sideways the horse could usually keep it moving.
But this is speculation.
There may be more information to come, and the ship may have been pivoting on the rock with no interlocking.
Is it reasonable that the rock could be supporting so much weight that it was that difficult to pull off and yet do no damage to the hull?
I don't know.

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

 

[TugboatEng]

Remember the picture I posted of the canal depth. A full third of the ship was in shallow water. There was certainly a lot of stiction involved. A dredge was brought in to dig out the bow. 20,000 m³ of dirt was removed to free the ship.

 

[JohnRBaker]

Sometimes you have to wait for the stars to align:

How a Supermoon Helped Free the Giant Container Ship From the Suez Canal

Stronger tidal effect made it easier to partially float the Ever Given but also gave engineers a hard deadline

https://www.wsj.com/articles/how-a-...-the-suez-canal-11617040923?mod=djemalertNEWS

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

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

 

[dik]

Is stiction the 'suction' force exerted to resist removal? or is it the actual bearing. I can see if the rock was embedded in the hull it would act as a giant keyway.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[miningman]

Everyone here seems to assume the rock was a boulder. What if it was localazed bedrock??? How does that change all the previous assumptions?? One of the previously posted sections could support my hypothesis

 

[RedSnake]

Seems that is still is just sand and limestone..

BR A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[waross]

The logs were generally lying a full 3/3 on the ground.
The old horse loggers knew that it was easier to start the end of the log moving sideways to break the static friction and so start the log moving.
That they were able to move the stern 80 degrees but were not able to pull the ship backwards *strongly suggests that the rock or bedrock was acting as a key.
*"strongly suggests", not 100 percent but a high percentage of probability.

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

 

[LionelHutz]

I'm finding it hard to believe there was a large hard pointy rock that poked through the bottom of the ship and keyed it in place. The amount the bow was into the sand and on top of sand was enough to still hold it, even when the stern could move.

 

[SwinnyGG]

That they were able to move the stern 80 degrees but were not able to pull the ship backwards *strongly suggests that the rock or bedrock was acting as a key.
*"strongly suggests", not 100 percent but a high percentage of probability.

I don't think so.

I think until you dig into it, we (me included) just aren't used to thinking on the scale of the forces involved in moving a ship of this magnitude.

Look at it this way.... the Ever Given weighs 200,000 tons. Two hundred thousand tons. 400,000,000 pounds.

If even 10% of the tonnage of the ship (and I bet it was more than that) is bearing on wet saturated sand, the friction force alone to pull the ship out is 15,000 tons and change.

That means that if you were to just yank it out with tugs straight back, you'd need the full capacity of 38 of the most powerful tugs in the world. (Google says the most powerful tug is ~400 tons) And that doesn't even include any force due to suction, which I don't know how to calculate but I'd imagine is huge on the large area which was contacting the sand. Or the significant inertia of a 200,000 ton load which you have to overcome to get the thing moving.

The forces are gargantuan, no pointy rock required.

 

[WKTaylor]

With the blocking of the Suez canal by a container ship for over 6-days a sense of panic is arising in the maritime community

I have a military mind. Sadly the moment I saw that gigantic container ship stuck sideways, all I could think-of was the likely on-set of a catastrophic sabotage plot.

I could visualize a single jet dropping 2-#2000 bombs mid-ship... or heavy cruise-missiles or anti-ship missiles... screaming-in and blasting the ship in-half or thirds. Based on current experience, cleaning-out the debris [containers] and cutting-up the ship would take at least 4-years. Something like this might even require re-routing [digging] the canal AROUND the blockage and closing that section off indefinitely.

This should be a wake-up call for every major and minor country that relies on canals or waterways or bays [with necked entry water-ways] for an economic lifeline... and have giant container/cargo ships passing each other.

Mapping the World’s Key Maritime Choke Points

https://www.visualcapitalist.com/mapping-the-worlds-key-maritime-choke-points/

In my minds eye, I saw these oceanic choke-points but also saw many other water-way choke-points, thus...

Suez canal.
Panama canal.
Gibraltar.
Gulf of Aqaba.
Strait of Hormuz.
Entrance to the Red Sea.

St Lawrence River [into the Great-Lakes].
Mississippi River.
Missouri River.
Ohio River.
Hudson River.
Delaware River
Columbia River.
Sacramento River.
San Francisco Bay.
Arkansas River.
Rhine River.
Volga River.
Mekong River.
Ganges River.
Yangtze River.
Nile River.

To name a few of the biggies...


Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

 

[Spartan5]

I have a military mind. Sadly the moment I saw that gigantic container ship stuck sideways, all I could think-of was the likely on-set of a catastrophic sabotage plot.

I could visualize a single jet dropping 2-#2000 bombs mid-ship... or heavy cruise-missiles or anti-ship missiles... screaming-in and blasting the ship in-half or thirds. Based on current experience, cleaning-out the debris [containers] and cutting-up the ship would take at least 4-years. Something like this might even require re-routing [digging] the canal AROUND the blockage and closing that section off indefinitely.

I mean... once you’re adding #2000 bombs and cruise missiles into the equation... does it really matter if the ship is stuck at that point? Just sayin’.

 

[hokie66]

Yes, the 'rock' was a furphy, a figment of someone's imagination. Ever been through the Suez? There is nothing but sand.

Then we had folks on this very site advocating for blowing the ship in place, or dumping the cargo in the canal.

Ludicrous, and some of these folks are the same ones who insist on 'following the science' in other respects.

 

[1503-44]

Here's a few more to worry about. Sweet dreams.

Malaca Strait!
Danish Strait!
English Channel!
Houston Ship Channel!
Dardenalles Strait (Bosporus)!
Sunda Strait! (Java)
Amazon River
Rio de la Plata (Buenos Aries)
Strait of Meagellan & Punta Arenas Channel
Yellow River
Los Angeles Harbor?
San Francisco?
San Jaun de Fuca?

Actually there are some high cliffs to the west of Suez. Finding a rock isn't totally impossible.

 

[hokie66]

And in this part of the world, Singapore, all of the South China Sea, Taiwan Strait, Sydney Harbour, Port of Busan, Port of Yokohama...the list goes on.

 

[Lou Scannon]

...and then, there's the breaching of dams (tried and true war tactic)

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[Spartan5]

Then we had folks on this very site advocating for blowing the ship in place, or dumping the cargo in the canal.

Ludicrous, and some of these folks are the same ones who insist on 'following the science' in other respects.

You and I must be looking at different threads.

I did see some people with practical experience on this matter suggesting that the reporting of the incident wasn’t honest and that the situation was much more dire than it turned out to be. Yeah, they had suggested off-loading the ship and/or cutting it in half. But not a whole lot of talk otherwise of “blowing” the ship in place or wholesale “dumping” of the cargo in the canal.