Fazlur Khan

Caption	Fazlur Rahman Khan
Name	Fazlur Rahman Khan
Nationality	Bangladeshi
Birth date	April 3, 1929
Birth place	Dhaka, Bangladesh
Death date	March 27, 1982
Education	Bengal Engineering & Science University, Bangladesh University of Engineering and Technology, University of Illinois at Urbana-Champaign
Religion	Islam
Discipline	Architectural, Civil, Structural
Significant design	John Hancock Center, Willis Tower, Hajj Terminal, King Abdulaziz University, One Magnificent Mile, Onterie Center

Fazlur Rahman Khan (Bengali: ফজলুর রহমান খ়ান Fozlur Rôhman Khan) (April 3, 1929 - March 27, 1982), born in Dhaka, Bangladesh, was a Bangladeshi-American architect and structural engineer. He is a central figure behind the "Second Chicago School" of architecture, and is regarded as the "father of tubular design for high-rises". Khan, "more than any other individual, ushered in a renaissance in skyscraper construction during the second half of the twentieth century." He is also considered to be the "Einstein of structural engineering" and "the greatest structural engineer of the second half of the 20th century" for his innovative use of structural systems that remain fundamental to modern skyscraper construction. His most famous buildings are the John Hancock Center and the Willis Tower (formerly Sears Tower), which was the world's tallest building for several decades.

Biography

Fazlur Rahman Khan is from the village of Bhandarikandi in Shibchar Upazila, Madaripur District, Dhaka Division, Bangladesh. He was born on 3 April 1929, in Dhaka. His father, Khan Bahadur Abdur Rahman Khan, BES was ADPI of Bengal and after retirement served as Principal of Jagannath College, Dhaka.

Education

Khan received his bachelors degree from the prestigious Ahsanullah Engineering College,Dhaka(Now known as Bangladesh University of Engineering & Technology). A Fulbright Scholarship and a Pakistani government scholarship (as Bangladesh was East Pakistan then) enabled him to travel to the United States in 1952 where he pursued advanced studies at the University of Illinois at Urbana-Champaign. In three years Khan earned two Master's degrees — one in structural engineering and one in theoretical and applied mechanics — and a PhD in structural engineering.

Career

In 1955, employed by Skidmore, Owings and Merrill, he began working in Chicago, Illinois. During the 1960s and 1970s, he became noted for his designs for Chicago’s 100-story John Hancock Center and 108-story Sears Tower, the tallest building in the world in its time and still the tallest in the United States since its completion in 1974. He is also responsible for designing notable buildings in Bangladesh and Saudi Arabia.

Fazlur Khan's personal papers, the majority of which were found in his office at the time of his death, are held by the Ryerson & Burnham Libraries at the Art Institute of Chicago. The Fazlur Khan Collection includes manuscripts, sketches, audio cassette tapes, slides and other materials regarding his work.

Personal interests

Outside of work, Khan enjoyed spending time with his family (wife Liselotte and daughter Yasmin). He enjoyed singing, poetry, and table tennis. He was also heavily involved with creating public opinion and garnering emergency funding for Bengali people during the 1971 Bangladesh Liberation War. He created the Chicago-based organization known as Bangladesh Emergency Welfare Appeal.

Innovations

Dr. Fazlur Khan realized that the rigid steel frame structure that had "dominated tall building design and construction so long was not the only system fitting for tall buildings", marking "the beginning of a new era of skyscraper revolution in terms of multiple structural systems." Dr. Fazlur Khan's design innovations significantly improved the construction of high-rise buildings, enabling them to withstand enormous forces generated on these super structures. These new designs opened an economic door for contractors, engineers, architects, and investors, providing vast amounts of real estate space on minimal plots of land.

Tube structural systems

Khan's central innovation in skyscraper design and construction was the idea of the "tube" structural system for tall buildings, including the "framed tube", "trussed tube" and "bundled tube" variations. His "tube concept," using "all the exterior wall perimeter structure of a building to simulate a thin-walled tube, revolutionized tall building design." The constructions of most supertall skyscrapers since the 1960s, including the construction of the World Trade Center, Petronas Towers and Jin Mao Building, employ a tube structural system.

Framed tube

Since 1963, the new structural system of framed tubes became highly influential in skyscraper design and construction. Khan defined the framed tube structure as "a three dimensional space structure composed of three, four, or possibly more frames, braced frames, or shear walls, joined at or near their edges to form a vertical tube-like structural system capable of resisting lateral forces in any direction by cantilevering from the foundation." Closely spaced interconnected exterior columns form the tube. Horizontal loads, for example from wind and earthquakes, are supported by the structure as a whole. About half the exterior surface is available for windows. Framed tubes allow fewer interior columns, and so create more usable floor space. The bundled tube structure is more efficient for tall buildings, lessening the penalty for height. The structural system also allows the interior columns to be smaller and the core of the building to be free of braced frames or shear walls that use up valuable floor space. Where larger openings like garage doors are required, the tube frame must be interrupted, with transfer girders used to maintain structural integrity. This laid the foundations for the framed tube structure used in the construction of the World Trade Center.

, designed by Skidmore, Owings and Merrill with chief designer Bruce Graham and structural engineer Fazlur Khan. The building was completed in 1969.]]

Trussed tube and X-bracing

Khan pioneered several other variations of the tube structure design. One of these was the concept of X-bracing, or the "trussed tube", first employed for the John Hancock Center. This concept reduced the lateral load on the building by transferring the load into the exterior columns. This allows for a reduced need for interior columns thus creating more floor space. This concept can be seen in the John Hancock Center, designed in 1965 and completed in 1969. One of the most famous buildings of the structural expressionist style, the skyscraper's distinctive X-bracing exterior is actually a hint that the structure's skin is indeed part of its 'tubular system'. This idea is one of the architectural techniques the building used to climb to record heights (the tubular system is essentially the spine that helps the building stand upright during wind and earthquake loads). This X-bracing allows for both higher performance from tall structures and the ability to open up the inside floorplan (and usable floor space) if the architect desires. Original features such as the skin, pioneered by Fazlur Khan, have made the John Hancock Center an architectural icon.

In contrast to earlier steel-frame structures, such as the Empire State Building (1931), which required about 206 kilograms of steel per square metre and Chase Manhattan Bank Building (1961), which required around 275 kilograms of steel per square metre, the John Hancock Center was far more efficient, requiring only 145 kilograms of steel per square metre. and completed in 1974, was the tallest building in the world at the time of its construction]]

Bundle tube

One of Khan's most important variations of the tube structure concept was the "bundled tube," which he used for the Sears Tower and One Magnificent Mile. The bundle tube design was not only the most efficient in economic terms, but it was also "innovative in its potential for versatile formulation of architectural space. Efficient towers no longer had to be box-like; the tube-units could take on various shapes and could be bundled together in different sorts of groupings."

Concrete tube structures

The last major buildings engineered by Khan were the One Magnificent Mile and Onterie Center in Chicago, which employed his bundled tube and trussed tube system designs respectively. In contrast to his earlier buildings, which were mainly steel, his last two buildings were concrete. His earlier DeWitt-Chestnut Apartments building, built in 1963 in Chicago, was also a concrete building with a tube structure.}}

Sky lobby

The first sky lobby was also designed by Khan for the John Hancock Center. Later buildings with sky lobbies include the World Trade Center, Petronas Twin Towers and Taipei 101. The 44th-floor sky lobby of the John Hancock Center also features the first high-rise indoor swimming pool, which remains the highest in America. This was the first time that people could have the opportunity to work and live 'in the sky'.

Khan was honoured by President Barack Obama during his speech at Cairo University in 2009, referring to how he "built our tallest building," the Sears Tower.

References

Further reading

Weingardt, Richard G. "Engineering Legends: Great American Civil Engineers." ASCE Press, 2005.

Khan, Y. S. "Engineering Architecture: the vision of Fazlur R. Khan." New York: W. W. Norton & Company, 2004.

External links

Website dedicated to Fazlur Rahman Khan

Category:1929 births Category:American people of Asian descent Category:1982 deaths Category:Civil engineers Category:Bangladeshi people Category:People from Chicago, Illinois Category:Structural engineers Category:American people of Bangladeshi descent Category:Bangladeshi Muslims Category:American Muslims Category:Aga Khan Award for Architecture winners Category:American architects of Asian descent Category:Dhaka University alumni Category:University of Calcutta alumni Category:University of Illinois at Urbana–Champaign alumni Category:Burials at Graceland Cemetery (Chicago)