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@ Bashno
2024-07-20 22:20:54The Leaning Tower of Pisa (Italian: Torre Pendente di Pisa), or simply the Tower of Pisa (Italian: Torre di Pisa), is one of the world's most famous leaning buildings. It is located in the city of Pisa, in the Tuscany region of Italy, near the Pisa Cathedral in the Piazza dei Miracoli (Square of Miracles). The tower was originally built as the bell tower for the cathedral and was intended to visually attract people to it when construction began in 1173 AD. Its construction spanned 177 years.
$$Description of the Leaning Tower$$Externally, the Leaning Tower of Pisa appears as a cylindrical stone building with balconies and columns resting on a lower support base. The bell chamber is located at the top, and it lacks floors on the inside. The central part consists of a hollow cylinder, and the interior façade is built from intricately carved grey-white marble from the nearby city of San Giuliano. The exterior façade, however, is constructed from white-gray limestone brought from San Giuliano.
The tower leans towards the southeast at an angle of 3.99 degrees currently, down from its previous inclination of 5.5 degrees before restoration works conducted between 1990 and 2001. These restoration efforts involved horizontally shifting the tower's peak by approximately 3.66 meters from its center. Here are some specific specifications:
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Height: 55.86 meters on the lower side and 56 meters on the higher side.
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Weight: 14,200 tons.
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Diameter: 15.54 meters at the base.
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Circumference: 48.6 meters at the base.
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Number of steps: Approximately 294 steps, with fewer at the seventh floor.
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Wall thickness: About 4.9 meters at the base, and 2.48 meters at the belfry; tapering from bottom to top.
$$Story of the Leaning Tower's Construction $$Construction of the Leaning Tower of Pisa began in 1173 AD using white marble and was designed to reach a height of 56 meters. It was to be the third and final building in the Piazza dei Miracoli complex alongside the cathedral. After completing the third floor of the planned eight floors, construction halted due to observed instability in its foundations on the soft ground beneath. This pause coincided with wars among Italian city-states, leading to a century-long hiatus that inadvertently protected the tower from collapse by stabilizing its foundations.Engineer Giovanni di Simone resumed the tower's construction after this long hiatus. He sought to compensate for its lean by building additional upper floors longer on the shorter side. However, this exacerbated the tower's sinking into the soil below. Over subsequent centuries, various interruptions and proposed solutions aimed at addressing the lean finally saw its completion in the 14th century. Seven bells were subsequently installed, with the largest weighing 3,600 kilograms. In the early 20th century, the heaviest bell's operation was stopped due to concerns it could worsen the tower's tilt. Cement and other materials were injected into the foundations for reinforcement, but it continued to sink at a rate of 1.2 millimeters annually by the end of the 20th century. Consequently, it faced collapse risks, leading to closure in 1990 and cessation of all bell operations. Engineers undertook major projects to modify its tilt.
$$Current Stability of the Tower$$The tower's current stability owes to soil reinforcement beneath its foundations, allowing the tower to exert pressure on the ground below by providing spaces to redirect it opposite to its lean direction. This was part of a 1990 project led by engineer John Burland with 13 experts, costing over 30 million euros and lasting a decade. This project reopened the tower in 2001, marking the last of several efforts to maintain its stability. Adjustments to its tilt included shifting its center of gravity towards the bottom and north, placing weights to counter its southward tilt, using giant steel cables to tension the tower during project work, and adjusting its tilt after soil preparation. These cables were removed post-operation. Additionally, 60 cubic meters of mud were excavated from below the foundations through well-digging, then dried. Concrete columns were added underground, reaching 15 meters in length, to reinforce the foundations. Attempting to return the tower to its current state by pulling steel cables. The della helped
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