Institute of Northern Engineering: A Structural Reevaluation of the Collapse of World Trade Center 7

This is a study of the collapse of the 47-story World Trade Center Building 7 (WTC7) at 5:20 P.M. on September 11, 2001.
The objective of the study was threefold: (1) Examine the structural response of WTC 7 to fire loads that may have occurred on September 11, 2001; (2) Rule out scenarios that could not have caused the observed collapse; and (3) Identify types of failures and their locations that may have caused the total collapse to occur as observed.  more...