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Contemporaneous Structural Steel Specifications. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-3A) ***DRAFT for Public Comments***
Published
Author(s)
William E. Luecke, Thomas A. Siewert, Frank W. Gayle
Abstract
This report reviews the contemporaneous (1960s era) steel and welding standards used to construct the 110-story World Trade Center (WTC) towers. It describes the major structural elements in the towers and the many grades of steels relevant to the WTC investigation. Although ASTM International structural steel standards have evolved since the towers were built, the changes are generally minor and not significant for estimating mechanical properties.
Citation
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-3
World Trade Center, high rise buildings, building collapse, disasters, fire safety, fire investigations, terrorists, terrorism, steel structures, specifications, steels, standards, structural damage, structural elements, construction
Luecke, W.
, Siewert, T.
and Gayle, F.
(2005),
Contemporaneous Structural Steel Specifications. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-3A) ***DRAFT for Public Comments***, National Construction Safety Team Act Reports (NIST NCSTAR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=909040
(Accessed October 10, 2025)