Why is the leaning tower leaning to the side? Height, slope of the Leaning Tower
In Tuscany - one of - 10 km from the sea coast is the city of Pisa. All over the world, it is known for its unique architectural structure, the tower, which has a slope of 3 ° 54 '. Why is it tilted and how much is it fraught with its complete destruction ─ questions that have been worrying architects for many centuries. Only in recent decades has it been possible to carry out a complex of works aimed at its general stabilization and allowing us to look at the future of this “falling sight” with a certain degree of optimism.
So why is the leaning tower leaning?
In search of an answer to this question, one should not suspect the author of her project ─ XII century Italian architect Bonnano Pisano - in his inclination towards avant-garde. Just in that old era were the same hackers, as in our time. Having compiled the necessary documentation and proceeding on 9 August 1173 to erecting the bell tower for the Catholic Cathedral of Santa Maria Assunta, he was very surprisedwhen his offspring literally immediately began to lean to the side.
The trouble began after the first floor of the bell tower was erected, having a height of 11 m. A plumb line placed at its highest point showed that the deviation from the center line was 4 cm to the north. Work was interrupted, but since the construction of the Tower of Pisa was part of the construction of a common architectural complex, which also included the building of the cathedral and the baptismals belonging to it, their construction was continued.
Continuation of work
Only a hundred years later they turned back to the crooked bell tower, since the cathedral, which had been built for a long time, was in dire need of the bells that convened the congregation for prayer. That part of the building, which was erected by their predecessors, the new builders decided not to disassemble, but to build on it in such a way as to compensate for the unauthorized inclination of the Leaning Tower of Pisa. To this end, with its further construction from the northern (inclined) side, a height excess of 10 cm was laid.
However, when 8 floors were erected, and the height of the Leaning Tower reached 56.8 m, it turned out that, despite all the efforts, the deviation from the center line increased to 50 cm. It was dangerous to continue construction, and it was interrupted, abandoning four more in the project of floors.This epic, stretching for nearly two centuries, in 1360, was completed.
Today, due to the obvious mistake of the builders, this ever-falling bell tower has become one of the most famous architectural monuments in the world. By the way, answering the question of why the Tower of Pisa is tilted to the side, some art historians try to assert that this was exactly what was conceived by its creator Bonnano Pisano, but their point of view can only cause a smile.
According to the original project, the entire structure was to be faced with white marble, mined near Pisa. Documents from that era survived, telling how a team of 23 workers led by contractor Giovanni di Simone set off in April 1264 to the mountains, where she cut the necessary amount of stones, then transferred to a master named Reinaldo Speschale. In his workshop they were processed and turned into a decorative covering of the bell tower.
False arches and authentic colonnades
The first floor of the building, the one on which construction was interrupted at the very beginning, is the so-called arcature. This is nothing more than a series of false decorative arches located around the entire circumference.They are superimposed on the surface of the wall as plastic elements imitating a real arched structure.
Each of the subsequent floors is surrounded by galleries, the outer sides of which are colonnades, the classical capitals (upper parts) of which are the basis for closed arches. To the upper floor you can climb, breaking the 294 steps. These works will be rewarded many times with an excellent view of the city and the Field of Miracles from there - this is how they dubbed the square, on which, besides the tower, is the cathedral, the baptismal and the cemetery adjacent to them.
The tower, which became the laboratory of Galilee
In general, this unique bell tower, built in the style now called Roman-Pisan, is distinguished by extraordinary beauty and elegance. Looking at it, you do not want to think about why the Tower of Pisa is tilted, and not standing strictly vertically, like hundreds of thousands of buildings of this kind. With her beauty, she puts such questions into the background. The brainchild of medieval builders is fine, and the winners, as we know, are not judged.
It is curious that the history of this structure is associated with the name of the great astronomer, mathematician and physicist of the seventeenth century, Galileo Galilei, born in Pisa in 1642.Since the Leaning Tower of Pisa was tilted to the side, it was a very convenient place to conduct its experiments. It was Galileo who dropped objects of different masses, illustrating his scientific findings to students. Despite the fact that in previous years a number of researchers questioned this information, later discoveries showed its authenticity.
The tower, taken under the supervision of scientists
As mentioned above, even in the period of resumption of work on the construction of the tower, efforts were made to strengthen it. Since the bells were hoisted on her in 1360, she has not ceased to be the object of attention of the builders. In particular, over the centuries, the columns have repeatedly changed, located on the inclined side and periodically collapsing due to the fact that they bear an additional load.
Thus, the tower tried to give greater stability. Measurements were regularly carried out and are being carried out to determine how many degrees the leaning tower of Pisa is tilted and whether this value is increasing. Currently, in order to preserve the architectural monument, work is being carried out, mainly related to its foundation.
It is curious to note that modern researchers were finally able to answer the question with complete certainty ─ why was the leaning tower of Pisa? As it turned out, the soil beneath its southern part is more clay and silty than from the opposite side. This is what led to the uneven draft and skewing of the building at the very beginning of its construction.
Tower Rescue Options
For a long time, specialists from different countries were looking for an opportunity to protect the tower from falling, which, in their opinion, should have come sooner or later. The difficulty was that with the help of external supports this could not be achieved, since the construction of the framework would distort the overall appearance of the building. In this regard, the city authorities have announced an international competition for the best solution to the problem.
It should be noted that there was no shortage of witty and sometimes the most unexpected proposals. So, one of the contestants offered to put a sculpture of her pseudo-architect near the tower, so that he, holding up his hands, would support his crooked creation. Someone suggested building an exact copy of it near the tower, but with a slope in the opposite direction. Thus, the two sister towers would hold each other.There was even a project to connect the top of the tower with a constantly hanging balloon above it so that it would insure it against falling. However, there were quite serious technical proposals.
General parameters of the Leaning Tower
As a result, a completely unique technology was developed, which in 1990s allowed a number of preventive works, which not only excluded a further increase in the building's angle of inclination, but also made it possible to reduce inclination by 0.5 °.
Due to the slope, the height of the south and north sides of the building is not the same. So, from the inclined (northern) side it is equal to 55.8 m, and from the opposite side it is 56.6 m. At its base, the tower has a diameter of 15.55 m with a wall thickness of 4 m, whereas at the height of galleries this value does not exceed 2.5 m. It is estimated that with such dimensions the mass of the Tower of Pisa is 14453 tons. The tilt angle remains almost the same and equals 3 ° 54.׳
Bells sounding through the centuries
Since this architectural monument to this day is the bell tower of the existing Cathedral of Santa Maria Assunta, everyone can hear the ringing of his seven bells at the appropriate time, the oldest of which was cast in the middle of the XIII century.It is characteristic that during the Middle Ages the bells of the Leaning Tower of Pisa did not ring at the same time - each of them had to announce a certain liturgical hour. At the end of December 1986, by decision of UNESCO, the entire complex of the Field of Miracles in Pisa was given the status of a monument belonging to the World Heritage.