Chicago, IL - September 12, 2001 - The American Institute of Steel
Construction, Inc. (AISC) has contacted FEMA and the leading structural
engineering associations and is forming a special task force to investigate
the structural collapses of the World Trade Center buildings resulting from
the terrorist attacks on September 11, 2001.
AISC is the technical institute responsible for developing and maintaining
the standards for design and construction of steel buildings in the United
States. Information developed by this task force will enable AISC to
determine if modifications are needed in existing standards.
"AISC strives to create a steel building specification that makes use of the
latest available design data and construction technology," said Nestor R.
Iwankiw, AISC's Vice President of Engineering and Research. "The special
task force of nationally recognized experts will investigate and determine
the various factors that contributed to the collapses and make
recommendations to AISC's Specification, Blast and Fire Committees."
Much speculation is currently underway about the cause of the collapses.
Most engineers currently believe the collapses occurred as a result of a
combination of extraordinary events, including the initial aircraft impacts
and explosions, which destroyed part of the structure, and the subsequent
extreme fire, which progressively weakened the remaining structure. The
ensuing collapses may have occurred when the weight of the buildings above
the points of impact exceeded the reduced load carrying capacity of the
remaining structure. It is believed that the collapse of the 47-story
building adjacent to the twin towers was caused by a combination of its
foundations and structure being weakened by the collapsing twin towers and
"We're saddened about this terrible disaster and the loss of life," said
AISC President H. Louis Gurthet, P.E. "Our hearts and prayers go out to the
victims and their families."