The leaning tower of Pisa?

Question

At what rate is the leaning tower of Pisa falling, and how long would it be before it would be completely prone?

Answer 1

Rate of Fall = 1.2 mm (1/20") every year.

It was closed to the public in 1990, after fears that an entire busload of tourists at the top would be enough to make it fall. Eleven years later, the lean has been corrected a little, but not entirely.

A British engineering professor came up with an idea. His plan was to remove ground from under the high side, instead of trying to add ground under the low side. In 1999 work began, and was done very slowly, so that the building wouldn't get a sudden shock. At the beginning of June 2001, the work was complete, and the tower had been straightened up by about 16 inches, which returns it to the position it held in 1838. The engineers believe that it is safe for at least another 300 years.

Answer 2

The tower is famous for its noticeable lean. It was intended to stand vertically, to serve as a bell tower, but began leaning soon after construction started in 1173.

After the third floor was built in 1178, the tower acquired a lean, due to a mere three-meter foundation in weak, unstable subsoil. The design of this tower was flawed from the beginning. Construction was halted for almost 100 years because the Pisans were almost continually engaged in battles with Genoa, Lucca and Florence. This allowed for the underlying soil to settle, otherwise the tower would almost certainly have toppled. In 1198 some clocks were temporarily installed on the unfinished construction.

In 1838 the architect Alessandro Della Gherardesca excavated a walkway around the tower to make the base of the tower visible again. This caused a flooding of the base and again an increase in the inclination. Benito Mussolini ordered the tower be returned to a vertical position, so concrete was poured into its foundation. The results were unexpected and sank the tower further into the soft soil.

On February 27, 1964, the government of Italy requested aid in preventing the tower from toppling. A multinational task force of engineers, mathematicians and historians was assigned and met on the Azores islands to discuss stabilization methods. After over two decades of work on the subject, the tower was closed to the public in January 1990. In the time that the tower was closed the bells were removed to relieve some weight and cables were cinched around the third level and anchored several hundred meters away. Apartments and houses in the path of the tower were vacated for safety concerns. After a decade of corrective reconstruction and stabilization efforts the tower was reopened to the public on December 15, 2001. Many methods were proposed to stabilize the tower including the addition of 800 metric tons of lead counterweights to the raised end of the base.[citation needed] The final solution to correcting the lean was to remove 38 m3 of soil from underneath the raised end. The tower has been declared stable for at least another 300 years.

Answer 3

I went and seen the leaning tower of pisa back in 1999'. I dont know exactly what rate it is falling however they do predict that it will probably completely fall by the year 2020. Such a wonderful piece of history to see get destroyed....

Answer 4

Hi, I'm italian and I live near Pisa. I often go there and you can climb up the tower of Pisa, however the number of people who can climb up it is limited and you need to buy tickets first. But it's a wonderful experience! =) Bye!

Answer 5

I was just there two weeks ago and it still stands. An official at the top pf the tower, it has reopened and you can climb it, said the primary reason for the problem has been corrected and the tower should remain standing for centuries.

Just for your information.....Italy is full of leaning towers. Bologna (Sp?) has a few and there is one in Burano (near Venice) that looks like it will go down any minute.

Answer 6

never! They have monitoring system for the tower :

Since 1913
- Geodetic measurements

Since 1934
- Girometti-Bonechi pendulum
- Civil Engineers spirit level

Since 1991
- Accurate internal optical system
- Automatic system
with sensors for the measurement of:
1. wind
2. air temperature
3. solar radiation
4. seismic actions
5. inclinations
6. horizontal point movement
7. dimensional variation in vertical and horizontal sections
8. width of the fissures
9. masonry temperature
10. levels within the stratum

The measurements
- The measurements take place every 4 hours, though they can take place every 4 minutes
- The sensitivity of the length measurements is 1/100mm.

Answer 7

never! they fixed the leaning tower of Pisa.

:-)

Answer 8

the tower actualy have the base of sand. that's why it is leaning but that is too slow. it is about .6 cms per year..

but i don think it will completly demolisdhed since its speed of tilting is reducing and hopefully it will stop and we have the wonder with us.

Answer 9

They spent the last few decades stabilizing it. It's good for another 500 years.

Answer 10

they have actually figured out a way to make it stop leaning and it is actually starting to go erect