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The Structural Steel of the World Trade Center Towers



Frank W. Gayle, Stephen W. Banovic, Timothy J. Foecke, Richard J. Fields, William E. Luecke, Joseph D. McColskey, Thomas A. Siewert, Christopher N. McCowan


In September 2002, the National Institute of Standards and Technology became the lead agency in an investigation of the World Trade Center (WTC) disaster of September 11, 2001. The investigation addresses many aspects of the catastrophe, from occupant egress to factors affecting how long the towers stood after being hit by the airplanes, with the goal of gaining valuable information for the future. A major part of the investigation is the metallurgical analysis of structural steel from the WTC. The analysis includes characterization of mechanical properties, failure modes, and temperature excursion seen by the steel. This overview on the metallurgical investigation describes the structure of the towers, steel recovered from the site, and special issues faced in the analysis of the steel.
Advanced Materials And Processes
No. 10


building technology, metallurgy, World Trade Center


Gayle, F. , Banovic, S. , Foecke, T. , Fields, R. , Luecke, W. , McColskey, J. , Siewert, T. and McCowan, C. (2004), The Structural Steel of the World Trade Center Towers, Advanced Materials And Processes (Accessed June 13, 2024)


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Created October 1, 2004, Updated February 17, 2017