Skyscraper
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(Texts copied from the Skyscraper Wikipedia article)
Skyscraper
A skyscraper is a very tall, continuously habitable building. There is no official definition or a precise cutoff height above which a building may clearly be classified as a skyscraper. However, as per usual practice in most cities, the definition is used empirically, depending on the relative impact of the shape of a building to a city's overall skyline. Thus, depending on the average height of the rest of the buildings and/ or structures in a city, even a building of 80 meters height (approximately 262 ft) may be considered a skyscraper provided that it clearly stands out above its surrounding built environment and significantly changes the overall skyline of that particular city.
The word skyscraper originally referred to a nautical term tall mast or its main sail on a sailing ship. The term was first applied to buildings in the late 19th century as a result of public amazement at the tall buildings being built in Chicago and New York City.
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, which passed their practical limit in 1891 with Chicago's Monadnock Building. Philadelphia's City Hall, completed in 1901, still holds claim as the world's tallest load-bearing masonry structure at 167 m (548 ft). 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 almost entirely with reinforced concrete. Pumps and storage tanks maintain water pressure at the top of skyscrapers.
A loose convention in the United States and Europe now draws the lower limit of a skyscraper at 150 meters (500 ft). A skyscraper taller than 300 meters (984 ft) may be referred to as supertall. Shorter buildings are still sometimes referred to as skyscrapers if they appear to dominate their surroundings.
The somewhat arbitrary term skyscraper should not be confused with the slightly less arbitrary term highrise, defined by the Emporis Standards Committee as "...a multi-story structure with at least 12 floors or 35 meters (115 feet) in height." All skyscrapers are highrises, but only the tallest highrises are skyscrapers. Habitability separates skyscrapers from towers and masts. Some structural engineers define a highrise as any vertical construction for which wind is a more significant load factor than weight. Note that this criterion fits not only highrises but some other tall structures, such as towers.
The word skyscraper often carries a connotation of pride and achievement. The skyscraper, in name and social function, is a modern expression of the age-old symbol of the world center or axis mundi: a pillar that connects earth to heaven and the four compass directions to one another.
Highest skyscrapers by architectural detail
1 Taipei 101 Taipei Republic of China (Taiwan) 509 m 1,671 ft 101 2004
2 Shanghai World Financial Center Shanghai People's Republic of China 492 m 1,614 ft 101 2008[B]
3= Petronas Tower 1 Kuala Lumpur Malaysia 452 m 1,483 ft 88 1998
4= Petronas Tower 2 Kuala Lumpur Malaysia 452 m 1,483 ft 88 1998
5 Sears Tower Chicago United States 442 m 1,451 ft 110 1973
6 Jin Mao Tower Shanghai People's Republic of China 421 m 1,380 ft 88 1998
7 Two International Finance Centre Hong Kong Hong Kong, China 415 m 1,362 ft 88 2003
8 CITIC Plaza Guangzhou People's Republic of China 391 m 1,283 ft 80 1997
9 Shun Hing Square Shenzhen People's Republic of China 384 m 1,260 ft 69 1996
10 Empire State Building New York City United States 381 m 1,250 ft 102 1931
