LEANING TOWER PISA , ITALYSubmitted to : Ma’am ShaziaRoll No : CE14AR37

The History of The Leaning Tower of PisaHumans make mistakes, after all, no human is perfect. One mistake made in the 11th century resulted in a 14,500 ton leaning tower. This miscalculation would later become a symbol of civic pride, but tell that to the man who designed it!The learning tower of Pisa, known as Torre Pendent di Pisa in Italian, is different than most medieval architecture. This particular section won't cover the highly advanced construction techniques that were used, it is important to mention how this tower's design is significant.The Leaning Tower is the third oldest building on Pisa's Piazza del Duomo (cathedral square), the Cathedral and Baptistery were first.Utilizing many columns and arch's, this tower represents an advanced understanding of weight and load characteristics, showing the Italian architectures' knowledge.What the architect didn't account for however, was the base of the tower being built on a dense section of clay.

The Early Years

• The construction of the Tower of Pisa began on August 9, 1173. Originally designed to be a bell tower, the tower actually stood upright for over 5 years, but just after the completion of the third floor (1178) it began to lean. The citizens of Italy were shocked as it began to lean ever so slightly.• The foundation of the tower, only 3 meter deep, was built on a dense clay

mixture and impacted the soil. As it turned out, the clay was not nearly as strong enough as required to hold the tower upright, and so the weight of the tower began to diffuse downward until it had found the weakest point.• After this, construction halted for 100 years. The government hoped that the soil

would settle, giving it enough strength to hold the weight of the tower. As well, the country was focused on its war with Genoa, which was quite brutal and ravaging at the time.

Construction Resumes• After the 100 year hiatus, Giovanni di Simone stepped

forward in 1272and began to add four more floors to the tower. He actually managed to cause the tower to lean over more when he tried to compensate for the original lean by making one side of the upper floors taller than the other.

• In 1284 construction was halted again, this time because of the Battle of Meloria, in which the Pisans were defeated by the Genoans.

• In 1319 the 7th floor was finished. The bell-chamber was added in 1372, and then the tower was left alone until the 19th century.

• In 1838 Alessandro Della Gherardesca, an established architect, dug a pathway near the base of the tower so that people could see the intricately crafted base. The tower began to lean even more as a result, likely due to the decreased amount of support available within the soil.

Builders

• One possible builder is Gerardo di Gerardo. His name appears as a witness to the above legacy of Berta di Bernardo as "Master Gerardo", and as a worker whose name was Gerardo.• A more probable builder is Diotisalvi, because of the construction period and the

structure's affinities with other buildings in Pisa, but he usually signed his works, and there is no signature by him in the bell tower. Giovanni di Simone was heavily involved in the completion of the tower, under the direction of Giovanni Pisano, who at the time was master builder of the Opera di Santa Maria Maggiore. He could be the same Giovanni Pisano who completed the belfry tower.

World War Two

• This war was brutal and bloody for the entire world, and its effects were felt everywhere from America to rural Africa. In relation to the leaning tower of Pisa, however, it is pure luck.• When the American soldiers invaded, they were ordered to destroy any and all

buildings in order to neutralize the thread of enemy snipers. There were no exceptions to this rule, and hundreds of buildings were blown up as the forces steadily advanced over the Italian countryside. The only thing which prevented the leaning tower of Pisa from being destroyed was a retreat that took place shortly after the arrival of the Americans, necessitating no need to destroy the national monument.

Steadier than Ever

• In 1964, Italy asked help to prevent the Leaning Tower from toppling. They wanted to keep the lean though, because of its importance for Pisa's tourism. A team of engineers and historians came together on the Azores to discuss the problem. As a temporary measure, a leaden counterweight (800 tonnes) was installed.• In 1987, the Leaning Tower of Pisa was declared a Unesco World Heritage Site,

along with the entire Piazza Del Duomo.• In 1990, the Leaning Tower was closed. The bells were removed and the tower

was anchored.

• Reopened in 2001 for tourists, the leaning tower of Pisa is finally sturdy and safe. Naturally, climbing to the top of the tower has become the most popular tourist activity within reason, and for good reason: with a history as deep and as wrought with unfortunate circumstance as this one, it's hard not to get excited about.

Architectural Points• The height of the tower is 55.86 meter's (183.27 feet) from the ground on the low

side and 56.67 meter's (185.93 feet) on the high side. • The width of the walls at the base is 2.44 m (8 ft. 0.06 in). Its weight is estimated

at 14,500 metric tons (16,000 short tons).• The tower has 296 or 294 steps; the seventh floor has two fewer steps on the

north-facing staircase.• Prior to restoration work performed between 1990 and 2001, the tower leaned at

an angle of 5.5 degrees, but the tower now leans at about 3.99 degrees.• This means that the top of the tower is displaced horizontally 3.9 metres (12 ft

10 in) from the Centre.

Technical informationElevation of Piazza del Duomo: about 2 meter's (6 feet, DMS).Height from the ground floor: 55.863 meres (183 ft. 3 in), 8 stories.Height from the foundation floor: 58.36 m (191 ft. 5.64 in).Outer diameter of base: 15.484 meter's (50 ft. 9.6 in).Inner diameter of base: 7.368 meter's (24 ft. 2.1 in).Angle of slant: 3.97 degrees or 3.9 meter's (12 ft. 10 in) from the vertical.Weight: 14,700 metric tons (16,200 short tons).Thickness of walls at the base: 2.44 meter's (8 ft. 0 in).Total number of bells: 7, tuned to musical scale, clockwise.1st bell: L'Assunta, cast in 1654 by Giovanni Pietro Orlandi, weight 3,620 kg

(7,981 lb).

Technical information2nd bell: Il Crocifisso, cast in 1572 by Vincenzo Possenti, weight 2,462 kg

(5,428 lb.).3rd bell: San Ranieri, cast in 1719–1721 by Giovanni Andrea Moreni, weight

1,448 kg (3,192 lb.).4th bell: La Terza (1st small one), cast in 1473, weight 300 kg (661 lb.).5th bell: La Pasquereccia or La Giustizia, cast in 1262 by Lotteringo, weight

1,014 kg (2,235 lb.)6th bell: Il Vespruccio (2nd small one), cast in the 14th century and again in 1501

by Nicola di Jacopo, weight 1,000 kg (2,205 lb.)7th bell: Dal Pozzo, cast in 1606 and again in 2004, weight 652 kg (1,437 lb.).

Number of steps to the top: 296.

About the 5th bell: The name Pasquareccia comes from Easter, because it used to ring on Easter day. However, this bell is older than the bell-chamber itself, and comes from the tower Vergata in Palazzo Pretorio in Pisa, where it was called La Giustizia (The Justice). The bell was tolled to announce executions of criminals and traitors, including Count Ugolino in 1289. A new bell was installed in the bell tower at the end of the 18th century to replace the broken Pasquareccia.

Inner staircase from seventh to eighth (the top) floor

View from the top Pasquareccia bell

Entrance door to the bell towerView looking up

Assunta bell

External loggia

Inner staircase from sixth to seventh floor

Tower return to 1838 Position

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