Explanations: Columns Going Soft
The Column Failure, or
Heat from fires causes columns to lose most of their strength precipitating a
Endorsed in a paper
Why Did the World Trade Center Collapse?-Simple Analysis
by Bazant and Zhou. Uses
elastic dynamic analysis
"The structural resistance is found to be an order of magnitude less than necessary for survival."
Published on September 13, 2001.
pull numbers out of thin air
Reveals authors' ignorance of
structural engineering, and of the towers' design
"[... if the] majority of columns of a single floor were to lose their load carrying capacity, the whole tower was doomed."
Described as "simple and approximate," yet no other papers have quantitatively analyzed collapses.
Endorsed by Silverstein insurance claim investigation conducted by Weidlinger Associates Inc.