August 8, 2025

Naz Keskin

Yahya Akel Science High School

11th Grade

The sky, a place where some can find unique meaning and inspiration, is also a route for those who have skybound ambitions. A prime example of skybound ambition lies in the structural genius Bangladeshi Fazlur Rahman Khan, who once stated that “The technical man must not be lost in his own technology. He must be able to appreciate life; and life is art, drama, music, and most importantly, people.”

Fazlur Rahman Khan was born on April 3, 1929, in British-ruled India, later East Pakistan, which is now Bangladesh. He was brought up in the village of Bhandarikandii in the Faridpur District near Dhaka, where the tallest building he ever saw was only three or four stories high. He didn’t see a skyscraper until he emigrated to Chicago in 1950, when he was 21 years old. This monumental transition from a rural environment to a bustling city would ultimately shape his future ambitions in architectural innovation.

In 1962, architect Bruce Graham, from the firm Skidmore, Owings & Merrill (SOM), asked Khan, now an engineer, to advise him on the most economical structure possible to build a skyscraper. This request was a matter of survival: the world of architecture was wondering if skyscrapers had stopped making logistical sense. Mid-rise towers were still being built here and there, but superskyscrapers – such as the Empire State Building – seemed to be a thing of the past; they were simply too expensive to build. When Graham asked him for the most effective structure possible, Khan remembered the forests around his home in Bangladesh; he recalled how he had marveled at the resistance of a plant as light as bamboo. He went to the closest flower shop, came back with a small bamboo stick, and showed it to Graham. This moment marked the beginning of a groundbreaking partnership that would redefine skyscraper construction.

Graham was correct: The most effective structure for a skyscraper isn’t the conventional framework of steel beams and pillars, but rather a tubular design, reminiscent of a bamboo stick. Why? There are two crucial reasons. Firstly, this tubular structure excels in wind resistance, which is the primary challenge for skyscrapers. Secondly, by positioning the support structure on the building's façade, the interior space is liberated from the need for traditional pillars. This innovative approach not only maximizes usable floor area but also enables more efficient allocation of space. As a result, developers can create more units, ultimately increasing profitability. Using the tubular frame system, Graham and Khan built the DeWitt-Chestnut Apartment Building in Chicago. Inaugurated in 1965, it’s an exquisite building with 42 floors. The project laid the foundations for the framed tube structure used in constructing the World Trade Center. As the architectural world took notice, Khan’s revolutionary ideas began to take root and flourish in skyscraper design.

Since 1963, the framed tube structural system has greatly influenced skyscraper design. Khan described it as a three-dimensional structure made of interconnected frames or shear walls that form a vertical tube, capable of resisting lateral forces by cantilevering from the foundation. This design utilizes closely spaced exterior columns to support horizontal loads from wind and earthquakes. Approximately half of the exterior surface can be used for windows, enhancing natural light and views. Building on this success, Khan continued to push the boundaries of conventional engineering, seeking further innovations that would transform urban skylines.

The bundled tube design is especially efficient for tall buildings, reducing issues related to height. It also permits smaller interior columns, keeping the building’s core free of obtrusive braced frames or shear walls. However, when larger openings like garage doors are needed, the tube frame must be interrupted, with transfer girders maintaining structural integrity. Khan’s ingenuity did not stop there: he introduced even more concepts that would define the next generation of skyscrapers.

Khan also introduced the trussed tube design by applying X-bracing to the exterior of buildings, allowing for reduced lateral loads and increased usable floor space by minimizing the need for interior columns. He first used this technique in the John Hancock Center in 1965, giving the building its iconic look. In contrast to earlier structures like the Empire State Building and One Chase Manhattan Plaza, which required significantly more steel per square meter, the Hancock Center was much more efficient with its materials, using only 145 kilograms of steel per square meter. This trussed tube concept influenced many later skyscrapers, including the Onterie Center and Bank of China Tower. The legacy of Khan’s innovative designs began to resonate far beyond the buildings themselves, shaping the entire landscape of urban architecture.

Khan and engineer Mark Fintel introduced the concept of shock-absorbing soft stories in life cycle civil engineering to protect structures from strong earthquakes over time. This idea laid the groundwork for modern seismic isolation systems, allowing structures to move naturally during seismic events while maintaining material elasticity. To honor these contributions, the IALCCE established the Fazlur R. Khan Life-Cycle Civil Engineering Medal. These advancements highlighted Khan's commitment not just to aesthetics, but also to the safety and resilience of urban structures.

Fazlur Rahman Khan, the visionary behind many groundbreaking ideas, died in 1982 at age 52 from a heart attack. At the time, he was still working on the world’s tallest building, the Sears Tower (now the Willis Tower) in Chicago. Fazlur Rahman Khan didn’t just change how we build upward—he reshaped how we think about the relationship between form, function, and beauty in the modern world.