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M.Mouse
18th Nov 2014, 00:31
See ship bending here. (http://www.dailymail.co.uk/video/news/video-1136552/Watch-inside-cargo-ship-twist-contort-storm.html)

herman the crab
18th Nov 2014, 03:20
I hate to see it when it was really rough!

HTC

onetrack
18th Nov 2014, 04:19
"Right about that point, Aloysius wished he hadn't accepted the lowest bid from the tenders, for the construction of the ship ..." :(

Seriously - wouldn't a ships hull be the same as a vehicle chassis? Chassis' are designed to twist and contort to an amazing level of distortion to cope with the stresses of driveline power and alterations in ground contours.
A chassis that is totally rigid, soon cracks, as many earlier chassis designers found to their dismay.

I'm a little surprised that the shipping people haven't found a way to lock all the containers together, to provide another structural member.
Then the designers and naval architects could lighten the ships hull even more!

porch monkey
18th Nov 2014, 04:51
No different to an aircraft fuse or wing.

RadarContactLost
18th Nov 2014, 05:49
Thats nothin' Now this. towboat (http://web.archive.org/web/20080504230717/http://koti.mbnet.fi/~soldier/towboat.htm). is impressive. :ok:

A Squared
18th Nov 2014, 07:37
I'm a little surprised that the shipping people haven't found a way to lock all the containers together, to provide another structural member.
Then the designers and naval architects could lighten the ships hull even more!

then what are you gonna do when he ship is unladen?

Ancient Mariner
18th Nov 2014, 08:36
If that video is from the "inside of a cargo ship", said ship is leaking.
Good fun walking along the weather deck when it is moving beneath your feet.
Per

rh200
18th Nov 2014, 08:50
Just Mr Young and his Modulus performing as planned.

Punters still arn't entirely comfortable with the whole concept of your jets wings flapping, now we have wriggly ships:p

joy ride
18th Nov 2014, 08:54
SS Connector was articulated:

?SS connector? (http://www.seabreezes.co.im/index.php?option=com_content&view=article&id=964:ss-connector&catid=6:letters-to-the-editor&Itemid=154)

https://www.google.co.uk/search?q=Steam+Ship+Connector&biw=1024&bih=475&tbm=isch&imgil=2eRgz7R2T6JD_M%253A%253B7WyyjG6keuFKpM%253Bhttp%25253A %25252F%25252Fwww.lookandlearn.com%25252Fhistory-images%25252FU254707%25252FThe-Jointed-Iron-Steam-Ship-Connector%25253Fimg%2525253D1%25252526search%2525253Dsteam%2 525252Bship%25252526bool%2525253Dphrase&source=iu&pf=m&fir=2eRgz7R2T6JD_M%253A%252C7WyyjG6keuFKpM%252C_&usg=__rg8xdqKUOOfJJ6Q63pRDZaQ-6Ao%3D&ved=0CDIQyjc&ei=zwlrVKCDEtPvaJSDgIgC

UniFoxOs
18th Nov 2014, 09:31
then what are you gonna do when he ship is unladen?

Presumably it won't need the strength if it isn't supporting the weight?

onetrack
18th Nov 2014, 09:57
then what are you gonna do when he ship is unladen?Ummmm ... we'll have a little brainstorming session and get back to you on that one ... :p

spekesoftly
18th Nov 2014, 10:33
wouldn't a ships hull be the same as a vehicle chassis? Chassis' are designed to twist and contort to an amazing level of distortion to cope with the stresses of driveline power and alterations in ground contours.Not sure that I can agree with that. Road vehicle chassis are normally designed to be as torsionally stiff as possible and it's the suspension that copes with ground contours etc. A chassis that twists will upset the suspension geometry that is set up to give the best ride comfort and handling compromise on domestic vehicles. (it's a complex subject and I'm no expert, but that's my understanding of the basics)

603DX
18th Nov 2014, 10:59
My only comments are:

Bette Midler's foghorn voice booming out in the initial ad made me jump and spill my coffee - should I claim from the Daily Wail?
The English in the captions is a bit eccentric, like the reference to "the so-called Engineers passageway" - hope the ship's so-called Engineers don't mind being called that ... ;)
I now feel seasick ...

RJM
18th Nov 2014, 11:40
Not sure that I can agree with that. Road vehicle chassis are normally designed to be as torsionally stiff as possible and it's the suspension that copes with ground contours etc. A chassis that twists will upset the suspension geometry that is set up to give the best ride comfort and handling compromise on domestic vehicles. (it's a complex subject and I'm no expert, but that's my understanding of the basics)

As a former owner of a 2CV, I refute that!

KING6024
18th Nov 2014, 11:58
Ships 'Work' in a seaway and they 'Hog' and 'Sag' depending on how they are loaded.


Colin A simple Sailor who once had a PPL.

VP959
18th Nov 2014, 12:15
Not sure that I can agree with that. Road vehicle chassis are normally designed to be as torsionally stiff as possible and it's the suspension that copes with ground contours etc. A chassis that twists will upset the suspension geometry that is set up to give the best ride comfort and handling compromise on domestic vehicles. (it's a complex subject and I'm no expert, but that's my understanding of the basics)

Commercial vehicle chassis are designed to twist and flex a LOT. They deliberately make them so they are torsionally flexible, otherwise they just crack and break.

A common technique with trucks is to use a pair of C section members for the chassis longitudinal members, often laminated with bolted joints. Cross members are bolted on to take the axles, body attachments etc. If you look at a truck you'll see all the bolted joints, rather than welded joints, which is another method used to avoid cracking.

If you want to see how much flex a truck chassis has, take a look at one when one wheel mounts a kerb. You'll see the whole chassis twist, and if it has a box body with hinged rear doors, watch the rear doors as the body twists and the doors move up and down in the centre relative to each other.

FLCH
18th Nov 2014, 12:25
Ships 'Work' in a seaway and they 'Hog' and 'Sag' depending on how they are loaded.



Sounds like a couple of Flight Attendants working the flight. ;)

SLFguy
18th Nov 2014, 13:17
Sounds like a couple of Flight Attendants working the flight.


That was 'Dog and Shag' surely..

onetrack
18th Nov 2014, 13:37
If you want to see how much flex a truck chassis has, take a look at one when one wheel mounts a kerb. You'll see the whole chassis twist, and if it has a box body with hinged rear doors, watch the rear doors as the body twists and the doors move up and down in the centre relative to each other.I've watched a heavy duty International prime mover (truck-tractor to the cousins) as it commenced moving off from a standing start - pulling a 4 trailer roadtrain with 100 tonnes payload - lift one front wheel a full 6" (150mm) off the ground, as the driver engaged the clutch, and gunned the big Cummins engine.

Notice the style of chassis cross-member design and riveted attachment in the pic below. The cross-members are designed to allow the chassis side rails to flex.

http://oi58.tinypic.com/2jg80lw.jpg

rgbrock1
18th Nov 2014, 13:41
Although not a ship, truck or car I do very well remember the feeling of the World Trade Center towers (before they were destroyed) swaying slightly in heavy winds. A very disconcerting feeling at first, especially when you're swaying at 100+ floors up! :eek:

Solid Rust Twotter
18th Nov 2014, 14:19
You is a better man than I Gunga Rock. That would have had me crawling on the floor, holding on to furniture and walls with my teeth and refusing to go within fifty feet of a window.

No problem wearing a BASE rig though. Security blanket?

rgbrock1
18th Nov 2014, 14:25
SRT:

When I felt the building swaying like that my first thought was: where's my T-10 and where the hell is the static line. :E:}

dazdaz1
18th Nov 2014, 14:46
My friend Julian from Brighton was most disappointed with the OP title, he thought it might have been somewhat to his way of thinking.

MagnusP
18th Nov 2014, 15:18
I always found it a little spooky when, at the top of Sydney's Centrepoint tower, you could watch the display of the magnitude of deflection on a windy day. :eek:

Fareastdriver
18th Nov 2014, 16:00
As I understand it very large container ships have to have containers, full or empty, up to the main deck line to maintain hull integrity.

1DC
18th Nov 2014, 16:46
I only ever sailed on oil tankers and for the first seven or eight years the bridge was amidships and we lived amidships.I never saw any indication that the ship was bending apart from the creaking and heaving in a seaway. The design changed and the bridge and accommodation was put at the after end. The first time i went on an aft bridge the ship was 900 feet long and when we got into a big swell in the bay of Biscay I couldn't believe how much the ship was bending and shaking, i couldn't believe how I could have missed it in the earlier years.
I was also very surprised to see how much a Boeing 747 bent and twisted in turbulence when i was sat on the back row in an aisle seat looking forward.From that day Mrs 1DC has refused to sit at the back, working on the principle that if she can't see it she can assume it isn't happening..

tony draper
18th Nov 2014, 18:45
Well to me these days they all look like they were built by the people who used to make those biscuit tins wi pictures of Cockington Forge or Edinburgh Castle on the top. :rolleyes:

Shaggy Sheep Driver
18th Nov 2014, 19:04
The most vivid example a bendy springy fuselage I've experienced was on the flight deck of a Concorde as it taxyed to the runway. The noseleg is almost 40 feet behind the flight deck and every time the nosewheel bumped over a join in the taxyway the entire flight deck bounced up and down, to the extent that it was difficult to take a photograph.

tdracer
18th Nov 2014, 22:31
I recall sitting in the back of an L1011 many years ago in heavy turbulence watching the fuselage twist and gyrate. The relative movements of the overhead bins near the wing root was amazing.

Back in my college days, I lived on the top floor of a 15 story dorm for a while. After a Calculus final a couple of us had gone out and drank heavily. The next morning, when I woke up, the wind was blowing ~125 mph and the building was swaying :{ (although I had to check with my roommate to make sure it was the building and not me :sad:) When I went to the bathroom, water was sloshing out of the toilets :eek: :uhoh:

Gertrude the Wombat
18th Nov 2014, 23:31
I recall sitting in the back of an L1011 many years ago in heavy turbulence watching the fuselage twist and gyrate.
That's wot the curtains are for. They're not just to seperate the plebs from the toffs up front, they're also so that the punters don't get to see quite how much the fuselage twists.

Blacksheep
19th Nov 2014, 08:18
Never mind the bending and twisting, you should see some of the cracks we find on a 4C Check!

It doesn't bother me. I still happily fly around the globe whenever I have to. By the time it's 20+ years old I reckon there's only about 30% of the original aeroplane left. It's called maintenance. I suppose the same is true of ships.

TWT
19th Nov 2014, 08:27
Magnus P,Centrepoint Tower in Sydney is the safest place to be in an earthquake too.The steel cables attached to the tower allow a huge amount of sway.

I've been on the roof of the base building and up close to the cables.A good design.

joy ride
19th Nov 2014, 08:36
About 20 years ago I was sitting reading in my old 6th floor flat in Camberwell, South London when I felt the building start to sway very slightly. I was a bit puzzled and alarmed, then I heard the news that there had been a smallish earthquake in Wales, and it had been felt by others in high London buildings.

tartare
19th Nov 2014, 09:08
Flex is fine.
Long as she don't break.
Just like the wings on a BUFF eh?
Seem to remember some old film somewhere of them flexing in a jig during testing - huuuge deflection.
I quite like the arcuate wing on the 78 - the way you can see the opposite wing tips across the top of the fuse when it's flying.
Seen from behind they look most birdlike - beautiful example of form following function.

4mastacker
19th Nov 2014, 09:31
joy ride wrote:

...I heard the news that there had been a smallish earthquake in Wales, and it had been felt by others in high London buildings.

During a visit to RAF Chilmark on a "things that go bang" course, we were taken into the underground quarry where the bombs were stored. The guide/instructor pointed out cracks in the roof of the cavern, into which wooden wedges were driven. The purpose of the wedges was for them to drop out if the crack widened - the procedure was then to f***-**f quick out of the quarry. According to the guide, several wedges did drop out after that particular earthquake.

cumulusrider
19th Nov 2014, 11:02
Glider wings bend
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radeng
19th Nov 2014, 11:15
Looking at the start of the video, the sea state suggests a Force 7 (28 - 33 knots) or 8 (34 -40 knots), so hardly a 'storm'.

joy ride
19th Nov 2014, 11:47
the "quarry crack wedges" reminded me of an ancient Chinese earthquake detector which was surrounded by little frogs, and a ball would roll into the mouth of the frog facing towards (or away from?) the earthquake's location.

Not sure if it's true, but an old colleague had worked on large oil tankers. he told us that one night while he was sleeping the bow had ploughed into a huge wave lifting the stern clean out of the water for several seconds. The rear end counter-rotated from prop torque, waking him up by hurling him around his cabin. Is this account plausible or "exaggerated"?

Ancient Mariner
19th Nov 2014, 12:28
I would say "exaggerated". Quite common while in ballast, but apart from some rattling not a big deal. In the engine room you will hear the turbochargers doing their thing though.
Per

SLFguy
19th Nov 2014, 12:49
About 20 years ago I was sitting reading in my old 6th floor flat in Camberwell, South London when I felt the building start to sway very slightly. I was a bit puzzled and alarmed, then I heard the news that there had been a smallish earthquake in Wales, and it had been felt by others in high London buildings.

Coincidence.. I was about to say that some 30 years ago I was in my 16th floor flat in Camberwell when a similar thing happened.

To this day I don't know what caused it, there was no sudden jarring movement, the building just began to sway back and forward for a few minutes and then just stopped. :confused:

Blacksheep
19th Nov 2014, 12:57
In our hotel in Seattle, which like all the newish tall buildings was "earthquake proofed" and sat on shock absorbers, there was a swimming pool on the top floor. It was very windy and the hotel was swaying on its shock absorbers so the water in the pool was slopping backwards and forwards. A very 'interesting' sensation.

I asked an architect friend about this and he said it is normal to put large water tanks on the top of tall buildings as water is heavy and serving as an inertial weight, it damps the swaying. In our case, the weight was a swimming pool.

tony draper
19th Nov 2014, 14:06
It is prudent to live in a geologically stable land in the middle of a tectonic plate, yer own fault for living on one of the cracks at the edges.
:rolleyes:

MagnusP
19th Nov 2014, 15:03
FSL, there was a 4.5 in Carlisle in the 1970s. You're not out of the woods yet!

4mastacker
19th Nov 2014, 15:07
MagnusP wrote:

...there was a 4.5 in Carlisle in the 1970s.

Were any improvements reported? ;)

Mike744
19th Nov 2014, 16:21
I sailed on VLCC's (Very Large Crude Carriers) for over 20 years. The experience of being on the bridge of an all-aft accommodation vessel watching the movement of the foremast in heavy weather is incredible.
Ships need to flex, if not then there's problems.
Was on a smaller iron ore carrying vessel that developed hull & superstructure cracks all the time, drilling out cracks was a way of life :) Sadly its sister ship sank off Hong Kong with a great loss of life.

joy ride
19th Nov 2014, 16:27
SLFguy: thinking about the time I was at 3 homes AFTER my one in Camberwell, I reckon "about 30 years ago" is probably much closer than my original "about 20 years ago", sounds like the same quake.

tony draper
19th Nov 2014, 17:55
Tankers were ok if they did snap in half both ends tended to float.
They had a tendency to snap in half when loading alongside if you went about it wrong.
:)
This is what happens if you load containers full of ball bearings at the sharp end containers full of lead ingots at the blunt end and containers full of feather mattresses in the middle.
http://i11.photobucket.com/albums/a194/Deaddogbay/Deaddogbay002/YEMEN_111_zpsd56b0717.jpg (http://s11.photobucket.com/user/Deaddogbay/media/Deaddogbay002/YEMEN_111_zpsd56b0717.jpg.html)