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Global Structural Analysis of the Response of World Trade Center Building 7 to Fires and Debris Impact Damage, Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-9A)



Robert S. MacNeill, Therese P. McAllister


This report analyzes the global response of WTC 7 to fire-induced structural failures and the resulting sequence of component and subsystem failures to determine the events that led to the global collapse of the building. The analysis involved a finite element model of the entire building, which was developed in LS-DYNA. Preliminary work involved two-story and 14 story subassemblies. The 47 story global model was based on the original structural drawings as well as construction fabrication shop drawings for connections. The model included the primary structural components throughout the building, including exterior and core columns, floor framing beams and girders, floor slabs, column transfer truss structures, wind bracing truss members, and penthouse structures.
National Construction Safety Team Act Reports (NIST NCSTAR) -


building evacuation, emergency response, fire safety, structural collapse, tall buildings, World Trade Center
Created November 20, 2008, Updated February 19, 2017