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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.
"ardurous" not "arduous"... :-(
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
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 right besides the Empire Scat Building!
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"...
...built.
There was a baker who had become rather popular with his breads, sandwiches and soups. He experimented with new and wonderful, and sometimes not so wonderful meal idea. By accident one day a shelf bracket in his kitchen gave way and though nothing had gotten broken various item spilled onto the counter where he was making various products. In cleaning up the mess he scoped meats and chesses and sauces onto a flatten, by the shelf, bread dough. Being the experimental type and not wanting to waste his supplies he decided to put the results in the oven instead of throwing it out.
This was the first pizza, but it wasn't perfected as the dough seemed to be a problem. Regardless he found the meal was good and decided to offer it to his customers, one of which was a close friend and building contractor who had been given a contract for a tower. These fluffy pies were selling well but the bread was still a problem and he couldn't figure out what had gotten mixed in the accident to cause the bread to stay flat rather than rise and spill the toppings.
He got to talking with his building contractor friend and explored ideas as to how to make the dough stay flat. They thought they figured it out, with a hard object (shelf) suddenly against the bread dough to flatten it. The contractor had an idea, that he'd build the building just slightly off level so his good friend could drop the dough from a height that would flatten the dough as it hit he hard ground. And once the building was built they tried it, and it worked. They were going to many many such pies and become rich. Teh lower they dropped the dough, teh thicker the crust, the higher the thinner.
So theu went to work, moving dough ingredients and tools to make it and lots of water up the tower. Of course teh overflow of water that had to keep away from teh spot where they woudl drop teh dough, so the contractor made a drain that diverted the drained water to under the building. This pie production went on for a few months but another problem was discovered, a seasonal one... birds and more specifically bird poop. Seems the bread also attracted birds and the slight tilted angle of the building, upon which teh birds would purch, was also contributing to the collection of bird poop on the ground right where they would drop the dough.
Customer began to notice the underside of the pies and questionable taste. and there were many such customer and notables.
Anyways Italy started to become embarrassed with this "bakers invention" and decided to put a stop to it but realized it word had spread far about this new and wonderful pie invention. So they had to cover it up and deny it ever existed. So they renamed the tower of pizza to Pisa. As things were, teh water being directed under the building weakened the foundation and teh building has ever since continued to tilt more and more.
But the custom of dropping the dough from a height to flatten it, still exist today and some still do it outside, so check the bottom of any pizza you by for white spots.
This story details may be expanded by any other in the know...
Actually, they can be considered fact. I think you will find, however, that discerning minds would only consider one of the two works you mention as fact.
Perhaps you meant to say that neither can be known as fact.
Then again perhaps not. I doubt you meant to say that at all. Writing accurately would belie your selfish agenda; that is, attempting to compare the culmination of human discernment and human logic that is modern science to the culmination of human creativity that is religion.
Trying to do that shows me you aren't very scientific. But you know what? It also shows me that you aren't very religious.
-- arstchnca
--
I reckon they've actually done a really good job here. With modern equipment, I think that technically they could just fix the foundations and set it back to vertical. But if it's not leaning then it's not much of a tourist attraction anymore.
Stabilising an ancient tower in a still leaning position is pretty impressive.
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.
Hmmm, I wonder if there will be something similar for our "tower" in the future...
Conservationists estimated that the entire 14,500-MB structure would BSOD 'some time between 2030 and 2040.' Now the Vulnerable Windows of Microsoft have been stabilized and declared safe for at least another three centuries. The stabilization, which cost $30M, was accomplished by anchoring it in a virtual machine with multi-megabyte counterweights, while 70 GB of malware was removed from the side away from the vulnerabilities, and x86 opcodes were injected into the image to relieve the pressure. The open vulnerabilities have now returned to where they were in the late 20th century.
My stupid comment about a ton being 2000 kg did not factor into my calculations...
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.
So, it seems that those builders, besides not being able to choose a good place to begin with, were unable to extrapolate. Which part of "if this goes on" they couldn't understand?
If it were me, I would stop building when it started leaning, and do it over somewhere else. To reduce the cost, the stones could be reused, just take it apart and put it back together where the ground is more suitable.
You've got a point. Maybe they would have been better off spending all those stabilization funds on eliminating noobishness.
But... but, I don't want any of that... I want to... sing..
Lol, I thought it was Gal Civ 2 as well.
Beware of bugs in the above code; I have only proved it correct, not tried it.
Wow, parent gets 2 negative mods for not spotting a Python reference.. tough crowd!
This sig all sigs devours
Mod parent up. ;.)
The creator of this post (Jacob Smith) hereby releases it, and all of his other posts, into the public domain.
Insightful.
"When information is power, privacy is freedom" - Jah-Wren Ryel
don't sweat the mod system.....keep posting and you'll get some points and see how it works.
Did you see the BBC played Python all day on Memorial day? I watched it for about 5 hours....haven't watched MP in a long time, laughed my ass off, again.
It's not just the weight that makes a difference, soil and concrete act very differently. I don't know any more about what they did than you do, but I imagine that even using a big tower as a lever, pushing through a 70 ton block of concrete is going to be much harder than pushing through crappy soil, because the concrete is basically one giant piece. Even if you focus all of your energy on one particular section of the concrete, the strength of that material is going to spread out that force and so you'd end up having to move a lot more concrete/soil.
I don't know if that explanation makes much sense. It'd be easy to explain with a quick diagram, but I'm too lazy to draw with text.
One time I threw a brick at a duck.
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?
He's being repressed? Help! Help! We're being repressed!
Waa waa waaa! :) I've been modded "redundant" even though my post preceded the "first" one by several minutes. Unfortunately, I was further down the list "physically", so to speak. Moderators get confused.
It would be nice to add "redundant to which post" requirements, then auto-zapp the redundant modder if his reference post is actually newer than the "redundant" post.
In any case, back to the fun:
> the tower previously came close to collapsing in 1838, 1934,
> and 1995. (The commission convened in 1990 to study the tower's stability...)
Ahh, commissions at work.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
http://www.demotivators.com/med24x30prin.html
Damn interesting indeed! you should submit this to damninteresting.com!
Is it true that more people vote for the winner of American Idol, than vote for the president? -Ali G.
You've been modded off-topic because your guess at the origin of that quote is too obscure? The original is from this classic. Buy it, rent it, download it.
Geeks like to think that they can ignore politics, you can leave politics alone, but politics won't leave you alone.-rms
I guess it's better than "insightful".
Faster! Faster! Faster would be better!
I don't know why this is suddenly news, I saw a tv program on this, at least 5 years ago. They showed the cables and supports being fitted, and a few of the less successful methods too.
I order you to be quiet!
Insert funny smart-ass comment here.
it really embiggens the discussion
The summary has a error. Cementicious grout is injected under the tower to *increase* the bearing pressure of the soil, not to reduce it as stated in the the summary.
no text
That could never work. The Tower has to be infinitely high. Although I hear in some flat states they've tried to built it one story tall:
http://www.straightdope.com/classics/a3_341.html
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Gallileo had a blogographer? wtf?
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Like 4. Tower of Quattro.
Engineering is the art of compromise.
I wanted to see it come crashing down in my lifetime!
This sig is false.