Reply #68: RE: Leslie Robertson [View All]

[Make7]

 

"Another structural innovation was the outrigger space frame, which structurally linked the outside wall to the services core. This system performed several functions. First, gravity-induced vertical deformations between the columns of the services core and the columns of the outside wall were made equal at the top of the building; at other levels, the differential deformations were ameliorated. Second, wind-induced overturning moments were resisted in part by the columns of the services core, thus providing additional lateral stiffness. Finally, the weight of, and the wind-induced overturning moment from the rooftop antenna (440 feet tall) was distributed to all columns in the building . . . adding additional redundancy and toughness to the design."

Leslie E. Robertson. "Reflections on the World Trade Center". The Bridge Volume 32, Number 1

http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB

Were there concrete columns in the core?

- Make7