Burj Khalifa with Smith's attempts to make the crown more slender. The building opened on 4 January 2010. The tower was designed by Skidmore, Owings and Merrill (SOM), which also designed the Willis Tower (formerly the Sears Tower) in Chicago and the One World Trade Center in New York City. Burj Khalifa uses the bundled tube design of the Willis Tower, invented by Fazlur Rahman Khan. Due to its tubular system, proportionally only half the amount of steel was used in the construction, compared to the Empire State Building. Khan's contributions to the design of tall buildings have had a profound impact
U.S. Bank Building (Chicago) naming rights for the building through 2026. Notes U.S. Bank Building (Chicago) U.S. Bank Building, formerly 190 South LaSalle Street, is a tall skyscraper in Chicago, Illinois. It was completed in 1987 and has 40 floors. Johnson/Burgee Architects designed the building, which is the 57th tallest building in Chicago. From 1988-2016 the lobby of the building featured a tapestry by Helena Hernmarck titled "The 1909 Plan of Chicago" depicting the Civic Center Plaza proposed in the Burnham Plan of Chicago. In May 2013, U.S. Bank announced it agreed to increase its leased space in the structure from to . The