Physical Properties of Structural Steels. Federal Building and Fire Safety Investigation of the World Trade Center Disaster.
Physical Properties of Structural Steels. Federal
Building and Fire Safety Investigation of the World
Trade Center Disaster.
Banovic, S. W.; McCowan, C. N.; Luecke, W. E.
NIST NCSTAR 1-3E; 162 p. September 2005.
World Trade Center; high rise buildings; building
collapse; disasters; fire safety; fire investigations;
terrorists; terrorism; steel structures; physical
properties; chemical analysis; hardness; microstructure;
This report describes the physical properties of the
structural steel recovered from the World Trade Center
(WTC) towers. Analytical techniques were used to
determine and evaluate the chemistry, microstructure,
and thermal properties of the steels. While not a
physical property, hardness of the steels was also
measured and discussed in relation to strengthening
mechanisms of the material. The primary focus was on
structural components with known as-built locations from
WTC 1 and WTC 2. Evaluation of samples without known
as-built locations was conducted in order to fully
characterize all of the structural elements. The
physical property information was found useful in
helping to identify specific grades and producers of
steel used for the various components. In addition, the
thermal properties were developed for the use in the
models of the building response to fire. Although no
recovered structural elements were from WTC 7, physical
property data of steels from this building were
estimated based upon values found in the literature. In
addition to the structural steel, chemistry information
was measured for a piece of the aluminum facade used on
the WTC towers and the sprayed fire-resistive material
applied to the structural elements of WTC 2 and WTC 2.