Discussion of ''Weld Acceptance Criteria for Seismically Loaded Steel Structures''

The author reviews the causes of numerous beam-to-column weld fractures that occurred in steel moment frames during the 1994 Northridge earthquake. Using fracture mechanics, the author develops models for evaluating the fracture resistance of the 1995 Kaufman and Fisher pull-plate tests, shown in Fig. 3, where the load at failure and the flaw size are known, so that the material toughness at crack initiation could be derived. However, the Kaufman and Fisher monotonically loaded pull-plate test specimens do not represent the structural action and states of stress and strain that occurred during the earthquake in the beam flanges and welds of the ‘‘pre-Northridge’’ field welded‐field bolted, beam