Sears Tower
Although it no longer holds the title of world's
tallest building, the 110storey Sears tower is still a monument
to building technology. It is the fore-most example
of the bundled tube system of structural engineering, perfected
by SOM engineer Fazlur Khan in collaboration with design
architect Bruce Graham. The Sears consists of 9 bundled
tubes, but only two reach the entire height. The tower is 1454ft high.