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Leaning Tower of Pisa Secure For 300 More Years
Ponca City, We Love You writes "The tower of Pisa began to lean five years after its construction began, in 1178, and by 1990 it had tilted more than four meters off its true vertical. Conservationists estimated that the entire 14,500-ton structure would collapse 'some time between 2030 and 2040.' Now the Leaning Tower of Pisa has been stabilized and declared safe for at least another three centuries. The stabilization, which cost $30M, was accomplished by anchoring it to cables and lead counterweights, while 70 tons of soil were removed from the side away from the lean, and cement was injected into the ground to relieve the pressure. The tilt has now returned to where it was in the early 19th century. Nicholas Shrady, author of Tilt: A Skewed History of the Tower of Pisa, says that the tower was destined to lean from the outset because it was built on 'what is essentially a former bog.' Shrady adds that the tower previously came close to collapsing in 1838, 1934, and 1995. (The commission convened in 1990 to study the tower's stability was the 17th such.) Although Galileo Galilei is said to have dropped cannon balls from the tower in a gravity experiment, Shrady says the myth is the result of 'the overripe imagination of Galileo's secretary and first biographer, Vincenzo Viviani.'"
...tower of Pis began...The first of those is pretty obvious.
http://michaelsmith.id.au
Hmm, proof readers day off then?
I'm usually leaning when I have a tower of piss.
A slashdotting - you get the stick first and then the carrot !
I had Aug 2034 in the office pool.
You bastards.
He who said 1,000,000 monkeys on 1,000,000 typewriters would eventually type the great novel, never saw an AOL chat room
Hint: Remember when Supes straightened the Tower after being exposed to the tar-kryptonite?
N4st0r, trixx0r h0bb1tz0rz! Th3y st0l3 0ur pr3c10uzz!
Remarks like that are an open invitation for epic failure.
To me, the Leaning Tower of Pisa was a monument of how human mistakes live on for centuries, and it was a miracle it was still standing. Now they've gone and reinforced it and taken all the fun out of it. They might as well have straightened it... It was also funny to me how an utterly useless building (who'd want to work with gravity pulling you gently towards the open window?) is conserved simply because it's old. If the same thing had happened today, which it does on a regular basis, the building would have been torn down.
Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
Am I right?
Tower Of Pies
Crivens! I kicked meself in me own heid!
Another 300 years of putting up with Leaning Tower of Pizza jokes.
If each mistake being made is a new one, then progress is being made.
Listen, lad. I built this kingdom up from nothing. When I started here, all there was was swamp. Other kings said I was daft to build a tower on a swamp, but I built it all the same, just to show 'em. It sank into the swamp. So, I built a second one. That sank into the swamp. So, I built a third one. That burned down, fell over, then sank into the swamp, but the fourth one... stayed up! And that's what you're gonna get, lad: the strongest tower in these lands.
"If we let things terrify us, life will not be worth living."
- Seneca
yar....why ye be posting as AC?
you should be proud to attach your name to a post declaring your belief that the great pasta in the sky created all life
RAmen
-I only code in BASIC.-
Of course if they straightened it totally it would be worse, because the top leans the other way slightly as the builders attempted to compensate.
It's not completely regarded as a myth; there are a handful of Galileo scholars that think there may be some reality to it. It's all conjecture though, a single source of questionable reliability will forever make it impossible to distinguish myth from fact.
I'm sorry, this is totally off topic, but to get an answer to this, posting it in the first thread is my best chance, probably.
;)
I used to get 5 moderator points, then a while ago, I had 10, now I have 15... Does anyone have any clue what on earth is going on? Do they stack over time if unused?
And to stay slightly on-topic: I find it hilarious that they're fixing old engineering mistakes using modern engineering principles that are technically over 3000 years old
Coz eternity my friend, is a long *ing time.
Is Gal Civ 2 entirely written in Python, then?
Taken from "Monty Python and the Holy Grail"...
The concrete is probably mostly serving to make the apparent size of the hard foundation larger, so that it is pushing down on a great deal more soil, thus pushing down on each bit of soil quite a bit less.
70 tons of soil is something like 70 cubic meters of soil(on the low end, that's at density of 2g/cc and assuming ton means 1000 kg (where it either should mean either 900 or 2000, I didn't read the article)), which is 'only' a pad that is 12 meters by 12 meters by 0.5 meters. If you go with 0.25 meters, you get something like 25 meters on a side. If you start by figuring that the soil that was there was barely strong enough to do the job, it isn't surprising that a bit of concrete goes a long way.
Nerd rage is the funniest rage.
"I find that work perfectly cromulent."
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
Pretend like the moderation system doesn't exist and everything will take care of itself. People who pay too much attention to mods and their whims either don't last too long, take a serious karma hit for constantly complaining about the system, or end up like this guy http://slashdot.org/~RageTroll+9000/.
The end goal is more quality content (subjective), but plenty of individual unfairness happens too (also subjective).
If you fall into the demographic that enjoys slashdot, keep posting and pretend karma doesn't exist.
According to Wikipedia, they moved it about 45 cm, meaning 45 cm is the difference between toppling in the next few decades vs the next few centuries.
Given the way management works, I'd imagine the builders tried to do exactly that, only to be told by their superiors to continue working until it was finished, regardless of the outcome. If it fell, the workers would be blamed for their substandard work. If not, it would serve as a testament to management's foresight and proof of their competence to any who might have criticized their decision. In no case would the project's management ever be held to any kind of responsibility for anything bad that might happen.
It's the way it's always worked, and the way it always will work.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
Galileo was a smart man, certainly smarter than me. And even I know enough not to take a heavy weight to the top of something that's fixin' to fall over. Unless it was a "Hey, Bubba, watch this!" moment.
Mod parent up. ;.)
The creator of this post (Jacob Smith) hereby releases it, and all of his other posts, into the public domain.
That's the problem with slashdot moderation. You can clearly see the violence inherent in the system.
The tower is built on alluvial silt, and that's pretty nasty stuff to build on. Modern techniques for such poor soils rely on very large and very stiff concrete mats, like Chicago's skyscrapers, or on piles driven to bedrock like at the beach. One of the temporary stabilizing measures they used for the tower was to stiffen the soil by pumping liquid nitrogen through pipes to freeze the groundwater in the silt to prevent it from subsiding more on the side of the tilt until they figured out a more permanent solution.
If you look at pictures of it (I guarantee, pick any geotechnical book and Pisa will either be the cover or in the first chapter), you'll notice a subtle banana shape. The builders over time knew it was tilting, so they started correcting as they were building.
Another fascinating thing about the tower is that the walls are built of rubble clad with marble facing. The rubble over time subsided, and now the entire weight of the tower is bearing on the thin marble. Some of the tilt-side masonry is under enormous stress, and the very fine joints keep most stress concentrations low.
The book cited in the the summary, Tilt, was an excellent history of Pisa, because the history of the city is completely entwined with the history of the tower. A very fine read, though the hardback book is cut at an angle, so the book, when shelved , tilts back into the shelves.
Why does my coffee mug smell like trout?