Every time someone looks up at the Chicago skyline and takes in the Willis Tower or the John Hancock Center, they’re looking at the work of a structural engineer born in Dhaka in 1929. Fazlur Rahman Khan didn’t just design a couple of famous buildings, he fundamentally rewrote the engineering rules that made modern skyscrapers structurally and economically possible, and his influence on how tall buildings get built has never really gone away.
From Dhaka to a Fulbright Scholarship
Khan was born on 3 April 1929 in Dhaka, and studied civil engineering at Bengal Engineering and Science University in Shibpur, India, before a combination of a Fulbright Scholarship and a Pakistani government scholarship opened the door to graduate study in the United States. He went on to earn two master’s degrees there, laying the technical foundation for a career that would eventually reshape an entire field of structural engineering.
The Problem He Actually Solved
To understand why Khan mattered so much, it helps to understand the problem he was working against. For most of the 20th century, tall buildings were engineered using a rigid frame system, essentially a dense internal skeleton of steel columns and beams distributed throughout the entire floor plate, which worked but became progressively more expensive and materially wasteful the taller a building got, since resisting wind and lateral forces demanded more and more internal structure as height increased.
Khan’s breakthrough was the tubular structural system, an idea that treated the entire building as a hollow, rigid tube rather than an internal skeleton needing support throughout. By concentrating a building’s structural strength around its perimeter rather than spreading it evenly through the interior, a tube-based building could resist wind and seismic forces far more efficiently, using significantly less structural steel while opening up much larger, column-free interior floor space. It’s hard to overstate how significant this was: Khan’s tube concept, and the several variations he developed from it, the framed tube, the tube-in-tube, the trussed tube, the bundled tube, and composite systems blending concrete with structural steel, became the structural basis for nearly every major supertall building built afterward, right up to the present day.
The Buildings That Proved the Idea
Khan’s ideas weren’t theoretical for long. The John Hancock Center in Chicago, completed in 1969, put his trussed tube system on dramatic public display, its distinctive X-shaped exterior bracing isn’t decorative, it’s the structural system itself, visible on the building’s skin rather than hidden inside it.
Then came the building that made his reputation permanent: the Willis Tower, known as the Sears Tower when it opened in 1973. Its design used what’s called a bundled tube system, nine square structural tubes bundled together, rising to different heights and interconnected for stability. That approach let the building climb to 1,450 feet, becoming the tallest building in the world at the time, a record it held for a quarter of a century until 1998, all while remaining structurally efficient and offering genuinely flexible interior floor plans rather than the cramped, column-heavy interiors that older skyscraper engineering would have demanded at that height.
A Legacy That Outlasted the Century
Khan died in 1982, at just 52, but the engineering principles he developed didn’t stop mattering when he did. Nearly every supertall building constructed in the decades since, from later American skyscrapers to the current generation of the world’s tallest towers in the Middle East and Asia, owes a structural debt to the tube concepts he pioneered. The engineering profession has continued to formally recognize this: the Council on Tall Buildings and Urban Habitat named one of its most significant honors the Fazlur Khan Lifetime Achievement Medal, and Lehigh University established an endowed chair in his name, the kind of lasting institutional recognition reserved for figures whose work reshaped an entire discipline rather than simply excelling within its existing boundaries.
Why This Story Deserves Wider Recognition
Khan’s story sits at an interesting intersection that doesn’t get told often enough: a Bangladeshi engineer, educated first in Dhaka and Shibpur before a scholarship carried him to the United States, ends up quietly responsible for the structural logic behind some of the most recognizable buildings on the planet. It’s a genuinely global story of Bangladeshi talent and training producing world-changing results, the kind of achievement that belongs in the same conversation as any other great engineering legacy, precisely because so few people who admire the Chicago skyline, or any supertall building built since, know whose fundamental insight made it structurally and economically achievable in the first place.
The Bottom Line
Fazlur Rahman Khan took a genuine engineering problem, the punishing cost and inefficiency of building truly tall, and solved it with an idea elegant enough to become the default approach for an entire generation of architecture that followed. From a civil engineering classroom in Dhaka to reshaping the Chicago skyline and, by extension, supertall construction worldwide, his career stands as one of the clearest examples of a single Bangladeshi mind leaving a permanent mark on how the modern world literally gets built.