Global Structural Analysis of the Response of the World Trade Center Towers to Impact Damage and Fire. Chapters 1-3. Federal Building and Fire Safety Investigation of the World Trade Center Disaster.
Global Structural Analysis of the Response of the World
Trade Center Towers to Impact Damage and Fire. Chapters
1-3. Federal Building and Fire Safety Investigation of
the World Trade Center Disaster.
(16929 K)
Zarghamee, M. S.; Kitane, Y.; Erbay, O. O.; McAllister,
T. P.; Gross, J. L.
NIST NCSTAR 1-6D; Chapters 1-3; 230 p. September 2005.
Keywords:
World Trade Center; high rise buildings; building
collapse; disasters; fire safety; fire investigations;
terrorists; terrorism; structural analysis; damage;
walls; plastics; stability; deflection; structural
responce; impact
Abstract:
Simpson Gumpertz & Heger Inc. (SGH) developed global
models of the World Trade Center (WTC) towers using
finite elements to gain an understanding of the roles of
the aircraft impact damage and the subsequent fires in
the WTC towers with respect to structural stability and
sequential failures of components and subsystems and to
determine the probable sequence of structural responses
that led to initiation of global collapse. The study was
conducted as part of the investigation on the WTC
disaster by the National Institute of Standards and
Technology (NIST). The developed finite-element global
models of the WTC towers simulated the structural
performance of the part of the buildings in and above
the aircraft impact zone. These models captured the
nonlinear responses of the towers subjected to the
aircraft impact damage and the subsequent fire effects.
The nonlinearities included in the global models were
temperature-dependent material properties such as
thermal expansion, plasticity and creep of metals, large
deflection and the resulting instability, and failure
modes of members and connections. NIST provided
temperature-dependent nonlinear material properties,
estimates of aircraft impact damage to structural
members, and temperature time histories of structural
elements, which were used as input in this study.