Skyscrapers
Until one hundred years ago, the skylines of the world's cities were characterized by silhouettes of trees and church towers, but as urban populations have grown, urban land has become extremely valuable. To keep up with the demands of the population but still provide affordable retail, office, and living space, builders have developed methods of constructing vertical rather than horizontal buildings.
The urban skyline began to experience change in 1883 when William Le Baron Jenney designed the first skeletal frame building, the Home Office Building in Chicago. Jenny's innovations opened the way for many other architects to literally soar to enormous heights. Among those moving in the direction Jenny had established were Louis Sullivan (1856-1924), William Holabird (1854-1923), and Daniel Burnham (1846-1912).
Many innovations occurred around the end of the nineteenth century that contributed to the success of the skyscraper. Rolled steel beams were introduced by the Butterfly Company in 1880 and provided building material for the structures. The first commercial elevator was designed based on drawings by Elisha Graves Otis and installed in the Demarest Building in New York City in 1889. (Steam-powered elevators had been introduced as early as 1857.) Subsequently, cities like Chicago and New York experienced a flurry of competition among industrial corporations. The new buildings filled many city blocks with large, steel-framed buildings that had facades of brick and masonry. Many famous buildings, including the 102-story, 1,250 ft (381.0 m) Empire State Building, were built during this time.
Although construction virtually came to a halt during the Great Depression and World War II, it resumed with a vengence after the war. However, the ornate facades of earlier designs were replaced by streamlined glass and steel. Although the new materials represented progress and sophistication, they also became symbols of the insensitivity and impersonality of modern living. For the first time, psychological studies became a part of the building design process.
During the 1970s and 1980s, architects began to move away the cold, utilitarian designs of the previous decades, once again adding variety to their work. Postmodern architects such as Robert Venturi and Michael Graves returned to the use of color and shape so that a building could once again be identified by its appearance, rather than simply by its address. Stress-skin construction, in which the load-bearing frame is incorporated into the external wall, began with the 1982 completion of the One Mellon Bank Center in Pittsburgh. The new method allows the architect more freedom in the placement of floor supports rather than having support columns dictate design.
Some cities have rejected high-rise construction. Many European cities like Milan and Paris have opted to retain their historical character by keeping their older structures and expanding outward instead of upward.
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