A New era in the skyscrapers was marked by the revolutionized design concepts of Mr.FazlurRahman Khan. And made possible to build wonders such as burj khalifa-829.8m(tall).He is a Bangladeshi-American structural engineer from Chicago. He was born on 3rdapril 1929 in Dhaka Bangladesh.
Until 1960’s skyscrapers design was limited with only framed structures and only of maximum 40 stories was possible. And all this limitations were broken by the idea of tubular structure by Fazlur R Khan. He did his under graduate program in Bengal Engineering College in Civil Engineering. Then he obtained scholarship for doing masters in structural engineering and Theoretical & Applied Mechanics in University Of Illinois at urbana-Champaign. He did his PhD in Structural Engineering.
He started out his career by joining Skidmore,Owings AndMerril which is one of the largest architectural firm in the world. He introduced his tube structure system in Chestnut De-Witt apartment building. It was 43 storey building and was proved to be successful. The tube structure was found to be much more efficient in bearing lateral load which was a major concerns in tall building designs.
The main disadvantage of using framed structure design concept for skyscraper designs,is lesser floor area. The tubular concept is about providing closely packed columns at the outer perimeter and thus avoiding number of columns in the interior. Thus it acts as a cylinder with being thick at the perimeter and hollow at the interior.It proved efficient in transferring the lateral loads by cantilever action from the ground surface. Another great advantage was the lesser usage of steel which proved to be economical.
This concept offered unprecedented flexibility in creating architectural space and new possibilities for architectural expression. New kind of creative architechural designs were possible through this method. One of his statements on designing, Khan said “When thinking design, I put myself in the place of a whole building, feeling every part. In my mind I visualize the stresses and twisting a building undergoes.” And this had been very well reflected in his works.
One of his another notable work is Willis tower-442m Chicago. With shear lag limiting the applicability of tube structure system, he brought in bundled tube concept for willis tower. Its design is very interesting with 9 square tubes in 3*3 matrix format bundled together.All tubes would rise upto 50th floor . At 50th floor the northwest and southwest tubes ends. At 66th floor the northeast and the southwest tubes ends.At 90th floor the north,south and east ends.With remaining west and centre tubes continuing upto 108thfloor.It is the tallest building in America with larger floor area than its rivals.
He modified his design according to the need of each building such as “trussed tube” system which was used in John Hancock Centre in Chicago, “Tube in Tube”system for One Shell Plaza in Bouston and “Composite tubes” in sears tower. Khan brought a new innovation in structural engineering by collabrating engineering and architecture. His collaboration with Bruce J. Graham, the design Architect has been seen in all his work and they both done many remarkable buildings. The relationship was so intense that when Graham died at 2010, he was buried next to Fazlur.
Fazlur was also a great teacher.His daughter Yasmin, who is a famous engineer and a writer shares in one of her blogs, of how he made maths interesting by playing a puzzle games such as how a number 6 could be derived using four four’s( (4+4)/4+4).This shows his innovativeness in teaching.
Some of the other works, he done are the Hajj terminal of King Abdulaziz International Airport, King Abdulaziz University, the United States Air Force Academy in Colorado Springs and the Hubert H. Humphrey Metrodome in Minneapolis.
His ideas sets the benchmark for the design of present wonders such as burjkhalifa.His life had been a great inspiration to all of us. He believed that engineering has much more to contribute to the design of buildings. Only when architectural design is grounded in structural realities, he believed — thus celebrating architecture’s nature as a constructive art, rooted in the earth — can “the resulting aesthetics . . . have a transcendental value and quality.”