Innovation Follows Program
World population by 1960 was about to burst at the seams. Or so it seemed. Capping the dramatic population increases of the first half of the 20th century, the 1950s' baby boom intensified people’s sense of an earth that was shrinking. Metropolitan centers in particular were pressed for space. Housing was needed
High-rise construction offered the perfect solution. Super-tall buildings could provide large amounts of floor area without having to be densely packed, one building upon the next. A portion of each city block that a high rise occupied could be left available for desirable city plazas and parks.
Despite these apparent advantages, super-tall building construction faced a critical deterrent: expense. Skyscrapers were simply too costly by modern development standards. A tower reaching as high as the Empire State Building could not be justified in economic terms.
It was a generally accepted "fact" of construction that taller buildings cost more to build per square foot of rentable floor area than shorter buildings. A rapid run-up in structure costs resulted from increased wind forces: in order to withstand greater wind effects, a tower's structural framework had to be strengthened and stiffened considerably with increasing building height. Developers, therefore, were dissuaded from building above the thirty-story range by this cost premium. They leaned instead toward constructing bulky, site-consuming edifices. It appeared that conditions in central business districts were bound to worsen, with every building site being completely filled.
It was at this critical moment in the development of the modern urban environment that Fazlur Khan entered the profession.
Filled with both ambition and optimism, and equipped with solid training in structural engineering, Fazlur Khan was undeterred by the mindset and technological difficulties that hindered tall building design. He recognized that the structural systems utilized for high-rise construction were not on a par with the modern scale of architecture,
Fazlur Khan's earliest contributions to the field developing the shear wall frame interaction system, the framed-tube structure, and the tube-in-tube structure
As the reach of tall buildings extended, Fazlur Khan resolved to discover structural systems appropriate for each new scale of architecture. Crafting rational architecture in cooperation with Bruce J. Graham, chief design architect in SOM's Chicago office, he united an exceptionally efficient "trussed-tube" structural system with an articulate, graceful form for Chicago's 100-story John Hancock Center.
When one looks at a text on tall-building design today, one finds these recognizable structure types: the framed tube, the shear wall frame interaction, the trussed tube, the bundled tube, and the composite system (also developed by Fazlur Khan). Though Khan developed structural systems for particular project needs, he based his innovations on fundamental structural principles that allowed them wide application. His developments are among today’s “conventional” systems for skyscraper design.
For the immense roof of the Hajj Terminal of the new airport in
Jeddah, Saudi Arabia intended to shelter 80,000 pilgrims at a time, waiting
for up to 36 hours he searched for a coherent scheme that was both efficient
and honored the spirit of the Hajj pilgrimage. The fabric roof structure melds a
traditional concept, that of the Bedouin tent, with sophisticated technology.
Twenty years after the airport's opening, this fabric roof and the space that
it creates continue to awe as well as comfort terminal users.