:"revolutionary bundled-tube structural design. ... The Sears Tower is actually a bundle of nine tubes, and is considered one of the most efficient structures designed to withstand wind. This is a great design for a skyscraper in Chicago, the "Windy City," where the average wind speed is 16 miles per hour. As the building climbs upward, the tubes begin to drop off, reducing the wind forces on the building. The Tower's heavy weight -- more than 440 million pounds -- is also supported by 114 piles sunk deep into the earth so that they stand firmly on hard, solid bedrock." | :"revolutionary bundled-tube structural design. ... The Sears Tower is actually a bundle of nine tubes, and is considered one of the most efficient structures designed to withstand wind. This is a great design for a skyscraper in Chicago, the "Windy City," where the average wind speed is 16 miles per hour. As the building climbs upward, the tubes begin to drop off, reducing the wind forces on the building. The Tower's heavy weight -- more than 440 million pounds -- is also supported by 114 piles sunk deep into the earth so that they stand firmly on hard, solid bedrock." |