Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Damage and Failure Modes of Structural Steel Components. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-3C) ***DRAFT for Public Comments***

Published

Author(s)

Stephen W. Banovic, Timothy J. Foecke

Abstract

This report describes damage characteristics, failure modes, and fire-related degradation of the recovered structural components from the World Trade Center (WTC) 1 and WTC 2. Assessment of the structural components was divided into pre- and post-collapse analysis. Pre-collapse analysis concentrated on impact damage sustained by the exterior panel sections, with assessment based solely upon photographic and video images. These images were also used to locate areas on the recovered and identified (i.e., known as-built location) panels with pre-collapse fire exposure. The second portion of the analysis focused on direct visual examination of the recovered steel elements. Of particular importance were the samples located near the airplane impacts (north face of WTC 1 and south face of WTC 2) and those where fire was known to exist prior to collapse of the buildings. Metallographic analysis of components with specific or unique damage patterns: was also conducted. The findings of this report were used for validation of the modeling efforts in the baseline structural performance and aircraft impact damage analysis, the reconstruction of the thermal environment, and the structural fire response and collapse analysis. WTC 7 steel was not evaluated in this study of the tower damage and failure modes.
Citation
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-3
Report Number
1-3

Keywords

World Trade Center, high rise buildings, building collapse, disasters, fire safety, fire investigations, terrorists, terrorism, steel structures, damage, failure analysis, failure models, steels, degradation, wall panels, columns, floors, structural elements

Citation

Banovic, S. and Foecke, T. (2005), Damage and Failure Modes of Structural Steel Components. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-3C) ***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=909048 (Accessed December 11, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created September 1, 2005, Updated February 19, 2017