Fracture reliability of a typical Northridge steel moment resisting connection

Examination of the Northridge fractured connections has revealed that the material as well as the manufacturing parameters associated with the fracture behaviour of these connections were largely random. This in turn implies that the fracture resistance of these connections was also random. With these observations in mind, a simplified two-dimensional model is used in this paper to evaluate the reliability of a typical pre-Northridge connection. Comparisons are made with available experimental and analytical evidence. It is found that the reliability of the connection is considerably enhanced through backing bar removal and the use of improved toughness electrodes. Further significant improvements may also be achieved through the use of nondestructive examination and, when appropriate, repair of the bottom flange weld.