#3 Aon Centre
Designed by the late Edward Durell Stone, the 88-storey skyscraper is the third tallest building in Chicago. The construction started in the year 1970 and in 1972 efforts brought fruit and the world got Aon Centre as one of the tallest steel structures which uses the same tubular steel frame structure to bear itself and give the building with its weather and earthquake defiant properties. The project for the Aon Centre was undertaken by Turner Construction Company. The Turner Construction company is a well known throughout Middle East, the company acted as project managers of Burj al Khalifah. The building also holds a record for the tallest marble clad tower. The height of the tower is 346 m.
[youtube]http://www.youtube.com/watch?v=5q6GtLPTydY[/youtube]
#2 Empire State Building
The Empire State Building is located at 350 Fifth Avenue in New York City, acclaimed to be the tallest steel structures ever built on the land of United States. It is observed to be the most iconic design among the steel structures, filmed in many of the Hollywood movies and Television Series making it the most famous among all the steel structures. It has made remarkable world records up till now among which; it holds a world’s fastest built time record of 13 months and it demonstrated a healthy rivalry against Chrysler Tower. It has a total height of 381m, 102 floors/ storeys, 6,500 windows, it took 7,000,000 man-hours, as a record five workers died during the construction of ESB and it was inaugurated by US president Herbert Hoover on May 1 1931.
[youtube]http://www.youtube.com/watch?v=nVzKzoFJkQo[/youtube]
#1 Willis Tower (formerly the Sears Tower)
The Willis tower was completed in the year 1974 which possessed a height of 442m. Initially there was a controversy and it took a lot of discussion, which one among the Petronas or Willis is the tallest steel structure? Well after a lot of discussion the answer came that the heights of antennas were not included while measuring the height of Willis tower since they were not a part of building’s component and with the construction of the 508m high Taipei 101 tower in 2004 this discussion became irrelevant. The Willis tower is still the world’s tallest steel structures in the world. Using the main concept from the Fazlur Rehman’s tabular structures, the building consists of nine tubes, which are actually nine skyscrapers side by side providing extra stability against the wind load. Observation decks were provided in order to provide spectacular sceneries to the individuals. After such a long search the Willis Tower is the tallest steel structure ever built on earth.
[youtube]http://www.youtube.com/watch?v=dXejXBX74OM[/youtube]
