High metal strength

The first skyscraper in the world was built on a metal frame.

The use of a metal frame as a supporting structure was first proposed by architect William le Baron Jenny. According to his design, the first skyscraper, HomeInsuranceBuilding, was built in Chicago in 1885.

In the first half of the last century, almost all significant skyscrapers, including the Empire State Building, the Chrysler Building and others, were built on a steel frame. Their only significant drawback was their traditional rectangular shape.

A true revolution in the design of high-rise buildings on metal frames was made by an American engineer of Bangladeshi origin, Fazlur Khan. He developed and for the first time implemented standard schemes of load—bearing structures that have become standards in high-rise construction - "load-bearing pipe", "pipe in a pipe", "pipe with inclined beams", etc.

These innovations have opened up space for imagination.: skyscrapers of complex shapes appeared — pyramids, irregular prisms, and others.

The Russian branch of the World Council on High-Rise Buildings and Urban Habitat (CTBUH) has compiled a list of the most famous foreign metal-framed skyscrapers.:

1. Willis Tower (Sears) Tower – built in 1973 in Chicago (USA), height 442 m. 110 floors, office building. In this building, Fazlur Khan used a shell-diaphragm structural system. Distinctive feature: the building consists of 9 square steel pipes forming a large square at the base, the structure is designed on three levels, gradually tapering upward. There are 2 television antennas on the roof (the end of the antenna reaches 527.3 m). There is an observation deck with balconies on the 103rd floor.
2. Empire State Building – built in 1931 in New York (USA), height 381 m. An office building. This is perhaps the most iconic skyscraper, and for 40 years it remained the tallest building in the world. Since 1986, the building has been a monument of history and culture of the United States. The building was built in just 410 days, surpassing the pace and height of two other skyscrapers under construction – Wall Street, 40 and the Chrysler Building. In 1945, an airplane crashed into the building between the 79th and 80th floors, which pierced through it. The fire was extinguished in 40 minutes and caused no significant damage to the steel structure of the building. As a result of the fire, only 14 people died. And the elevator operator, Ms. Lou Oliver, survived after falling in an elevator cabin from the 75th floor, thus entering the Guinness Book of Records. The building has observation decks on the 86th and 102nd floors.
3. Aon Centre – built in 1973 in Chicago (USA), height 346 m, 88 floors. An office building. A tubular steel structure is used. Upon completion, it was the tallest marble-faced building in the world. Subsequently, the marble began to crumble under the influence of severe weathering and had to be removed. In the 1990s, the building was faced with white granite.
4. The Centre – built in 1998 in Hong Kong, height 346 m, 83 floors. An office building. The main feature is that the building is entirely made of steel, which cost the developers $384.5 million.
5. John Hancock Centre - built in 1969 in Chicago (USA), height 344 m, 100 floors. Multifunctional complex (IFC). Feature of the building: hollow structure resembling a huge rectangular column. The building, designed by Fazlur Khan himself, used a shell structural system with diagonal connections of supporting structures located along the outer contour. Steel consumption was minimized, reducing the cost of construction by $15 million. The highest swimming pool in North America is located on the 44th floor of the building. The elevator takes visitors to the observation deck (94th floor) in just 39 seconds.
6. Minsheng Bank Building - built in 2008 in Wuhan (China), height 331 m, 68 floors. IFC. By the standards of high–rise construction, it is a long-term construction (it took 7 years to be built).
7. China World Trade Center III - built in 2009 in Beijing (China), 330 m high, 74 floors. The IFC is very similar in appearance to the famous Twin Towers. It is the tallest building in Beijing and one of the tallest in the area of high seismic activity.
8. The New York Times Tower (also known as the "New York Times Headquarters") was built in 2007 in New York City (USA), with a height of 319 m. (including antenna), 52 floors. An office building. The project of the world famous architect Renzo Piano. The latest energy-saving technologies were used during the construction.
9. The Chrysler Building was built in 1930 in New York (USA), with a height of 319 m. (with a spire), 77 floors. An office building. The magnificent Art Deco building, one of the symbols of New York, remained the tallest building in the city for almost a year. It is noteworthy that metal was used not only for construction, but also for the decoration of the building. On the corners of the 31st floor there are metal sculptures of eagles, stylized as figures that decorated the hoods of Chrysler cars manufactured in the late 20s, and on the 61st floor the famous gargoyles "settled". Stainless steel from Germany was widely used in the decoration of the building (including the arched crown and spire crowning the Chrysler Tower). In 2007, it was recognized by the New York City Architecture Commission as "The Most beautiful Skyscraper in Manhattan."
10. US Bank Tower - built in 1990 in Los Angeles (USA), height 310 m, 73 floors. The office building is sometimes referred to as the "library" because it was originally built as part of a program to reorganize the Los Angeles Central Library System. The building is the tallest in California, and $350 million was spent on its construction. The highest helipad in the world is installed on the roof. A skyscraper can withstand an earthquake of up to 8.3 on the Richter scale.