ARCHITECTURAL – WONDER OR BLUNDER?
Aon Center
The Aon Center is a modern skyscraper in Chicago, USA, designed by architect firms Edward Durell
Stone and The Perkins and Will partnership, and completed in 1973 as the Standard Oil Building. With 83 floors and a height of 1,136 feet (346 m), it is the third tallest building in Chicago.
The building employs a tubular steel-framed structural system with V-shaped perimeter columns to resist earthquakes, reduce sway, minimize column bending, and maximize column-free space. This construction method was also used for the World Trade Center towers in New York City.
When completed, it was the world's tallest marble-clad building, sheathed entirely with 43,000 slabs of Italian Carrara marble. The marble used was thinner than previously attempted in cladding a building; this proved to be a mistake. In 1974, just a year after completion, one of the marble slabs detached from the façade and penetrated the roof of the nearby building. Further inspection found numerous cracks and bowing in the marble cladding of the building. To alleviate the problem, stainless steel straps were added to hold the marble in place. Later, from 1990 to 1992, the entire building was refaced with white granite at an estimated cost of over $80 million.