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WTC Towers : Innovative Design Features and Structural Modeling.

pdf icon WTC Towers : Innovative Design Features and Structural Modeling. (126 K)
Lew, H. S.; Sadek, F.

TS 3-7-5 Fire Engineering (1);

Tall Buildings in Historical Cities: Culture and Technology for Sustainable Cities. Volume 2. Proceedings. Council on Tall Buildings and Urban Habitat (CTBUH) 2004 Seoul Conference. October 10-13, 2004, Seoul, Korea, Lee, L. H.; Klemencic, R.; Kim, S. D., Editor(s)(s), 1150-1153 pp, 2004.


high rise building; historic buildings; World Trade Center; disasters; building collapse; structures; fire safety; fire investigations; aircraft fires; injuries; fire fatalities; fire protection; occupants; human behavior; evacuation; building design; building construction; maintenance; fire codes; structural analysis; structural design; terrorism; terrorists


The National Institte of Standards and Technolgoy (NIST) is undertaking the federal building and fire safety investigation of the World Trade Center (WTC) disaster. The objectives of this investigation are to: (1) determine why and how the World Trade Center Towers collapsed following the initial impacts of the aircraft and subsequent fires; (2) determine why the injuries and fatalities were so high or low depending on location including all technical aspects of fire protection, occupant behavior, evacuation and emergency response; (3) determine what procedures and practices were used in the design, construction, operation, and maintenance of the buildings; and (4) identify areas in current building and fire codes, standards, and practicees that warrant revision. This paper presents innovative features that were incorporated in the design of the WTC towers and how the towers are modeled for structural analysis.