The Hancock Plaza building, which opened in 1970, was among his first to utilize so-called “tube” construction, an external steel frame instead of an internal cage of steel. Prominent X-shaped braces made the building instantly recognizable….
Mr. Graham insisted that not only did the unusual bundled tube structure make for a lighter building that used less steel, but that it was also stronger.
In a 2004 interview with the Port St. Lucie News, near where he had retired in Hobe Sound, Fla., Mr. Graham said that the 9/11 bombers would have been less successful hitting the tallest building in Chicago.
“If that plane would have hit the Sears Tower, the plane would have fallen, not the tower,” he said.