Engineer to Give Forensic Presentation on Collapses of World Trade Center Towers

PASADENA—Najib N. Abboud, associate principal and chief technology officer of the structural engineering firm Weidlinger Associates Inc., will give a presentation on the forensic investigation of the collapses of the World Trade Center's twin towers after the terrorist attack of September 11, 2001. The event will be held at 7 p.m. Wednesday, May 12, in Ramo Auditorium on the California Institute of Technology campus. The presentation is free and open to the public. Preferred seating will be given to invited guests.

Abboud and several other engineers of Weidlinger Associates conducted a study "to analyze the structural effects of the high-speed impacts of the Boeing 767 airplanes . . . to explain why the Twin Towers stood for as long as they did, and why they ultimately collapsed."

The series of analyses showed that, though the towers withstood the initial impacts, the flying debris stripped structural members of their fire protection, leaving the structures vulnerable to the weakening effects of the ensuing fires and leading to their ultimate collapse. The report also explains why WTC 2 collapsed after a shorter time from impact than WTC 1, and that the two collapses were independent.

The Caltech event will be the first time this WTC Collapse Forensic Study has been publicly presented on the West Coast.

Parking will be available in the lots on the north side of campus, which have entrances located along South Wilson and South Michigan Avenues south of Del Mar Boulevard. Directions and parking information are available from the Caltech Ticket Office (626) 395-4652, 332 South Michigan Avenue. For more information about the event, contact Diana Barnwell at (626) 796-7601. For information about the forensic study, contact Kendra Burnham at (310) 998-9154 (mail@hart.wai.com).