CONVENTION CENTER STEEL TRUSS COLLAPSE

Presented by Benjamin Lavon, P.E. at ASCE Forensic Congress
Washington D.C. / November 2009

ABSTRACT
Bow truss 13 failed during construction of the David L. Lawrence Convention Center in February 2002. Bow truss 13 was designed to withstand the gravity loads and horizontal tension loads from the roof suspension system. The truss itself required stabilization during erection proceedings to prevent it from toppling over. During construction a change order was introduced directing that the bow truss be
temporarily supported by a tension strut in lieu of the originally designed
compression strut. In addition, no clear erection procedure was given in the shop drawings for the tension strut. During construction, the connection fastening the tension strut to the foundation block failed. Bow truss 13 rotated forward and then to the side, landing on the ground killing one steel erector/iron worker and injuring two others. To prevent this kind of failure of a non-self-supported structure in the future, proper and clear erection notes should always be provided during construction.