Jan 12, 12:29 pm
Article on Skyscrapers (part 2) published: History and Technology
Skyscraper (part 2): The Rise of the Super-Block
George Katodrytis
The article was published in 2A (Architecture and Art) magazine, December 2006
History and Technology
Chicago is credited as the birthplace of the skyscraper. The word skyscraper was first applied to such buildings in the late 19th century, reflecting public amazement at the tall buildings being built in Chicago and New York. The structural definition of the word skyscraper was refined later by architectural historians, based on engineering developments of the 1880s that had enabled construction of tall multi-story buildings. This definition was based on the steel skeleton—as opposed to constructions of load-bearing masonry. The steel frame developed in stages of increasing self-sufficiency, with several buildings in Chicago and New York advancing the technology that allowed the steel frame to carry a building on its own. Today, however, many of the tallest skyscrapers are built more or less entirely with reinforced concrete.
The crucial developments for modern skyscrapers were steel, glass, reinforced concrete, water pumps, and elevators. Until the 19th century, buildings of over six stories were rare. The first modern skyscraper was the ten-storey Home Insurance Building in Chicago, built in 1885. In the 1950s, the Soviet Union planned eight massive skyscrapers dubbed “Stalin Towers” for Moscow; seven of these were eventually built. The rest of Europe also slowly began to permit skyscrapers, starting with Madrid in Spain during the 1950s. Finally, skyscrapers also began to appear in Africa, the Middle East and Australia from the late 1950s and the early 1960s. Currently Gulf and Asian cities lead the way in numbers of skyscrapers.
The historical evolution of the skyscraper can be traced in early 20thy century Manhattan. This simple grid, made a real estate layout that was facilitate buying and selling. The neutrality of the grid allowed for the individual blocks to be very different from each other. It forces the city to develop a new system of formal values to distinguish one block from another. The plan of the city becomes a series of urban fragments where each block is both unique and isolated. The Grid’s two-dimensional discipline, with its 2028 (12 avenues and 155 streets) blocks also creates a new freedom for three-dimensional anarchy.
Contemporary skyscrapers rely entirely on the elevator. Given that ear comfort and pressure changes do not usually affect elevator riders, unless the descent speeds exceed 7.0 m/s and the vertical travel exceeds 300 m., it will take considerable time to travel to the top and this will be in transit, i.e. changing vehicles.
Even if in 1823, an “ascending room” made its debut in London, it was not until 1853 that Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. The design of the Otis safety is somewhat similar to one type still used today. It consists of knurled roller(s) that lock the elevator to its guides should the elevator descend at an excessive speed, which is monitored by a governor device. In 1857 the first Otis elevator was installed at 488 Broadway in New York City.
The invention of the steel and concrete skeleton had other implications as well; that of repetition. The façade was now without any carrying function, a ‘curtain wall’. The steel skeleton made building spaces repetitive, flexible and open. Skyscrapers are sealed technological boxes. When Cass Gilbert defined the skyscraper as” machine that makes the land pay”, he was referring to the building’s ability to extract value through absolute repetition. Skyscrapers do not relate to the ground anymore but to the sky and its invisible telecommunications. They are part of a global system. Clad in glass or mirror the new skyscraper defies gravity and becomes translucent in an act of self-denial and disappearance.
But as buildings became taller and lighter, particularly the modern glass boxes that are so popular, skyscrapers began having trouble with wind and began to sway. Engineers came up with new solutions for this problem, first installing diagonally braced steel trusses between central elevator shafts to create a stronger core, and then moving most of the beams and columns to the outside edge of the walls in order to make a stiff tube. A more unusual solution was devised to control sway in the 1970s called a tuned mass damper. This is a giant concrete block or weight, mounted with springs and shock absorbers on a lubricated plate, designed like a pendulum to move in one direction when a computer senses the structure has begun to move in the other, in order to counterbalance the motion.
Despite advances made in the realm of structures, materials, and systems, the stylistic evolution of the skyscraper has occurred primarily in its cladding. The tower presents a new kind of camouflaged contextualism.
Not only does it epitomize the dream of every architect, but the 21st century is now bringing together, new elements: smart skin, responsive materials, parametric design in curtain wall technology, customization and digital fabrication.
Tall buildings will use “smart skins” that will respond to changes, environmental and emotional. Smarter programmable elevators will distribute traffic more efficiently vertically and travellators will do the same horizontally, between the lobbies of clustered skyscrapers.
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