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


In September of 2002, the National Institute of Standards and Technology began a two-year investigation into the World Trade Center (WTC) disaster of September 11, 2001. Now almost complete, the investigation addresses many aspects of the catastrophe, from occupant egress to structural stability, with the goal of gaining valuable information for interested parties, such as emergency responders and the structural code bodies. The complete plan and some initial reports from the NIST investigation are available at . A major part of the investigation is the metallurgical analysis of structural steel from the World Trade Center. The analysis includes characterization of the mechanical properties, failure modes, and temperature excursions seen by the steel. This report on the metallurgical investigation describes the structure of the towers, and properties of the steel recovered from the site at a range of temperatures and deformation rates.
Proceedings Title
Proc. Welding and Joining Conf.
Conference Location
Tel Aviv, 1, IS
Conference Title
Welding and Joining Conf.


building collapse, mechanical properties, strength, structural safety


Siewert, T. , McColskey, J. , McCowan, C. , Gayle, F. , Luecke, W. , Banovic, S. , Foecke, T. and Fields, R. (2004), FORENSIC STUDY OF THE STEEL IN THE WORLD TRADE CENTER, Proc. Welding and Joining Conf., Tel Aviv, 1, IS, [online], (Accessed May 20, 2024)


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Created December 29, 2004, Updated October 12, 2021