AON Center is a modern skyscraper located in the Chicago Loop in Chicago, Illinois. It was first known as the Standard Oil Building when it was first opened. It is currently the third tallest building in Chicago, with only the Willis Tower and the Trump International Hotel and Tower surpassing it in terms of height.
AON Center History
The AON Center was constructed as the Standard Oil Building. It was built as the new headquarters for the Standard Oil Company of Indiana which was previously situated in South Michigan Avenue and East 9th Street. It was completed in1973. During that time, it was considered as the tallest building in Chicago as well as the 4th tallest in the world. It changed names to Amoco Building when the company was renamed Amoco. It was eventually renamed the AON Center in 1999 when the building was sold and then took new tenants of which the AON Corporation became its primary tenant later on.
AON Center Profile
The AON Center stands 1,136 feet or 346 meters high. It comprises of 83 floors above the ground with another 5 floors located underground. It was designed by architect Edward Durell Stone and cost $120 million to make. When the building was completed it was also known as the world’s tallest marble-clad building. It was sheathed using a total of 43,000 slabs of Italian Carrara marble. But the marble was eventually replaced by Mount Airy white granite as some of the marble began to fall off dangerously over the building sides after a period of time.
AON Center Design
The building takes on a modern architectural style. It employs a tubular steel-framed structure using V-shaped perimeter columns that will allow the building to resist earthquakes as well as reduce swaying. This type of structural system also helps minimize column bending as well as maximize column-free interior space. AON Center is considered as the only regular box-shaped building in the world that stands over 300 meters tall.