Bolts Not Responsible for WTC Collapse

Jason Sandefur

Initial reports that an upcoming MIT study blames the collapse of the World Trade Center on bolts in the floor trusses appear to be erroneous.
The New York Post reported that the unpublished 150-page study faults the use of “single-bolt connections in the framework” of the towers as contributing to the structures� demise.
Those reports appear to be false. MIT professor Eduardo Kausel told FIN the articles were a “gross oversimplification” of the study he co-authored.
In fact, the trusses were attached to the exterior columns with a twin-bolt system supported by a gusset plate and multiple welds. The intense heat from the fires made the steel trusses sag in the middle, eventually causing the truss bolts to shear. But Kausel explained to FIN that the erection bolts � 5/8″ diameter ASTM A325 – were not faulty. “Those bolts were never intended to bear that load.” �2002 FastenerNews.com