This article is a research-evaluation article that contains technical information about the structures of skyscrapers, material and structure information about these structures, as well as the development of these skyscrapers from time to time in the world history and general information about some skyscrapers that will be an example for these developments.
First of all, I would like to talk about structural and material information along with general information about skyscrapers. Multi-storey buildings above a certain height are called “skyscrapers”. This name was first used in the USA shortly after the first tall buildings were built. The development of skyscrapers emerged as a reflection of various technological and social developments. The term skyscraper was originally applied to buildings of 10 to 20 floors, but in the late 20th century this term was used to describe unusually high-rise buildings, usually more than 40 or 50 floors.[1]
At the end of the nineteenth century, various technological advances occurred that came together to create skyscraper design and construction. These included the use of steel produced as a result of the Industrial Revolution, the invention of functional lifts in all respects, and techniques developed to measure and analyze structural loads and stresses. In traditional building design, the walls of the building supported the building and the longer the building had to be thicker. But this has changed in skyscraper buildings. Instead of the very hard walls needed by tall buildings, a rigid steel frame was asked to bear the weight of the building. Besides this steel frame, it is also an important component of reinforced concrete skyscrapers. Thanks to concrete, the skyscrapers were strengthened structurally by pouring them around steel bars against the twisting motion caused by the wind. Another important material for the construction of skyscrapers is steel, which is iron and carbon alloy. They are often used together in skyscraper construction to maximize the best properties of concrete and steel. For example, as I just mentioned, concrete can be poured around a steel beam to form a support column, and this support column can make the skyscraper to be built stronger. Various materials are used to cover the skyscraper frame. The boards that make up the outer walls known as “cladding” can consist of metals such as glass, aluminium or stainless steel, or wall materials such as marble, limestone.
The second feature that is considered in skyscraper designs is to calculate the effects of weather events on the skyscraper. The most important of these weather events is the wind, in my opinion, because the power of the wind affects the building more than the weight and content of the building. The designer of the building should ensure that the building is not overturned by a strong wind and that it is not shaken enough to cause discomfort to the people who will be there. Each skyscraper design is unique. The main structural elements used in the construction of skyscrapers are a non-load-bearing steel frame, a reinforced concrete frame to form the outer walls, and a series of support columns connecting the beams and other structural elements in the building. Since each design is innovative, models of tall buildings are first tested to determine the effect of wind on wind tunnels and their impact on surrounding buildings. The tests show whether the building is strong against the wind and tells if there will be a change in their structure accordingly.
After general information about skyscrapers, I would like to give information about skyscrapers built in different periods. The skyscrapers, built in these different periods, differ from each other as structural and materials used, along with the current that the architecture of the period was affected. The first tall building, now called the skyscraper, was built in the United States in the 19th century. The big fire in the center of Chicago, which broke out at the time, made people look for ways to develop new building technology and construction techniques. Under the leadership of the famous architects of that time, William Le Baron Jenney, Louis Sullivan, Dankmar Adler, Daniel H. Burnham and Martin Roche, a new school was born under the name “Chicago School” and the first tall buildings were built by developing a steel frame system. The “Home Insurance” building, built-in 1885 in Chicago by William Le Baron Jenney, was considered the world’s first tallest building by the “High Buildings and Urban Living Area Council”. The high-rise buildings with frame systems built in the 20th century are called the high-rise building and the first phase of Chicago period buildings. In addition, the invention and use of the elevator began during this period. During this period, Chicago was rebuilt at an unprecedented pace.[2]
At the beginning of the 20th century, with the development of technology, aesthetic examples came to the fore in material design and accordingly building design and facade decoration. The Flariton Building and the Metropolitan Tower of Life were important examples of this period. One of the tallest buildings and most important examples of this period until the First World War was the Woolworth Building, which was built in New York in 1913. The facade of this building was 241 meters high, decorated with Gothic motifs and covered with terracotta. The first example of cathedral-style office buildings, the building shed light on the future skyscraper architecture with its tower form and had a system carried by steel columns and beams, which were considered a commercial cathedral.
However, the high-rise building construction that stagnated during the First World War regained speed in the 1920s after the war. A competition was organized especially in 1922 to build the “most beautiful and diverse office building in the world”. More than 260 architects from 23 countries participated in this contest with their unique designs. Some designs were Gothic-inspired, while others reflected the Neoclassical style. Some designs had Art-Deco effects. As will be understood from here, this competition was a platform that allowed architects to present different styles that they were influenced by. The winners of this competition, Raymond Hood and John Mead Howells, now proposed the Gothic tower on the corner of Michigan Avenue in the north of the Chicago River. They wanted to add verticality to the horizontal of the United States and balance the change with Gothic touches from the French tradition. However, the works of other competitors were also to be discussed. The design of Adolf Loos, especially in the form of a large Dor column, officially challenged modern buildings designed by other contestants and winners for that period with their traditionalism.
“Less is more,” which emerged after the Second World War. The movement’s traces were also found in skyscrapers built at that time. In this period, simple designs expressing their materials and structures were used in the skyscrapers built, free from ornaments and motifs, functionality and rationality were prioritized. Normally applied to high-rise buildings, namely skyscrapers, its shape, base, body, heading shape was abandoned and glass and steel prism shapes with the same geometric shape were used from roof to floor. An example of this is, “Less is more.” The founder of the principle is the Seagram building, built-in 1958 in New York by world-renowned architect Mies Van Der Rohe.
After the Second World War, the negative effects of this war were left behind and new developments in technology-enabled another period to begin. In this period, the quality of concrete has been increased, heating, cooling, ventilation and lighting systems have been developed in the buildings and the floor areas of the building have started to be used more effectively. In addition, significant improvements have been made in the construction methods, construction and calculation techniques of the buildings and the first steps of computerized design have been taken. All this accelerated the development and change of tall buildings, namely skyscrapers. Less steel was used at the John Hancock Center, completed in Chicago in 1969, and the structure was made much more economical than the old examples. John Hancock Center has brought a new understanding of the concept of high-rise building functionally. Until then, the John Hancock Center has all of the various mixed functions such as offices, residences, towers, commercial areas, all of which are designed as offices or residences. Tall buildings made in the form of glass boxes ended in this period. Thanks to the development of technology, height is no longer a problem. With the opportunities offered by the developing technology, skyscrapers in different styles continued to rise.
In summary, although high-rise buildings, namely skyscrapers first appeared in America, in the late twentieth century, these structures started to be built frequently in the Far East and European countries and this height race was also carried out of America. Australia and the Middle East countries, especially the Far East countries, also participated in this altitude race. The winner of this height race is the Burj Khalifa structure, which was completed in 2009. The top floors of the tallest building in the world are made of steel and it is the first building in the world to be continued with a steel construction on reinforced concrete. In order to minimize the wind loads on the facades of the building, none of the facades of the building is designed flat and the corners are made in circular shapes.
REFERENCES:
- https://www.britannica.com/technology/skyscraper
- https://www.thoughtco.com/how-skyscrapers-became-possible-1991649http://www.madehow.com/Volume-6/Skyscraper.html
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