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Design and Construction of Structural Systems. Federal Building and Fire Safety Investigation of the World Trade Center (NIST NCSTAR 1-1A) ***DRAFT for Public Comments***



D A. Fanella, A T. Derecho, S K. Ghosh


This report describes the provisions that were used to design and construct World Trade Center 1, 2, and 7. Included is a summary of the major provisions in the codes and standards together with the loads and load combinations that were used to design the buildings. Methods used to proportion structural members and other components of the buildings are also discussed, as well as tests that were performed to support the design. his shown that the loads that were used to design the members were at least equal to those prescribed in the applicable codes and standards, and that the methods used to proportion the structural members followed the requirements in the applicable material design standards available at that time. Also included in this report are the innovative systems, technologies, and materials that were used in the buildings, and the Port Authority's acceptance procedures for such items. Fabrication and inspection requirements at the fabrication yard and inspection protocol during construction are discussed. Also covered are the details of the deviations to contract documents that were granted by the Port Authority, including the justifications for those deviations. The information contained in this report is based on documents and structural drawings that were acquired from the following locations: (1) the offices of the Port Authority of New York and New Jersey in Newark, New Jersey, and New York City and (2) the National Institute of Standards and Technology in Gaithersburg, Maryland. Paper, microfilm, and electronic versions of these documents were obtained from these locations. Appendixes to this report include copies of referenced documents.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-1
Report Number


World Trade Center, high rise buildings, building collapse, disasters, terrorists, terrorism, building design, building construction, structural systems, fire safety, fire investigations, building codes, inspection, standards, structural members, walls wind tunnels, floors, quality control, building materials, construction materials
Created September 1, 2005, Updated February 19, 2017