Gusset Plate

Gusset Plate

Gusset plates are thick sheets of steel that are used to connect beams and girders to columns or to connect truss members . A gusset plate can be fastened to a permanent member either by bolts, rivets or welding or a combination of the three. Gusset plates not only serve as a method of joining steel members together but they also strengthen the joint. They can be used in bridges and buildings along with other structures.

On August 1, 2007, the I-35W Mississippi River Bridge failed due to the improper design of the gusset plates. The plates that failed were found to be only a 1/2 inch thick rather than a larger size appropriate to the application; with an increase in loading due to alterations over the years, the gusset plates became even more inadequate. The National Transportation Safety Board attributed most of the cause of the failure of the bridge to this flaw.