Murrah Building Collapse: Reassessment of the Transfer Girder

The bombing of the Alfred P. Murrah Federal Building caused a progressive collapse that consumed nearly one-half of the building, killing 168 people. The use of a transfer girder along the front face of the building is often cited as the prime reason for the severity of the incident, although this paper provides evidence that suggests the transfer girder may not have been responsible. A method of predicting column failures attributable to blast is introduced and used to accurately predict the column failure pattern observed during the forensic investigation. The frame was adjusted with the transfer girder replaced with a conventional beam column arrangement. The failure pattern of the reconfigured building indicates that the extent of the collapse would be largely unchanged. This finding has important implications for the design of buildings that may be subjected to accidental or malicious damage. It is argued that the other buildings have demonstrated an ability to survive similar incidents and that the Murrah Building was vulnerable because it combined a glazed facade with open-plan architecture, in addition to lacking alternative load paths capable of redistributing loads after multiple column failures.