Seismic behavior of steel girder bridge superstructures

Recent earthquakes exposed the vulnerabilities of steel plate girder bridges when subjected to ground shaking. This paper discusses the behavior of steel plate girder bridges during recent earthquakes such as Petrolia, Northridge, and Kobe. The paper also discusses the recent experimental and analytical investigations that were conducted on steel plate girder bridges and their components. Results of these investigations showed the importance of shear connectors in distributing and transferring the lateral forces to the end and intermediate cross frames. Also, these investigations showed the potential of using end cross frames as ductile elements that can be used to dissipate the earthquake input energy. The paper also gives an update on specifications and guidelines for the seismic design of steel plate girder bridges in the United States.