Research on the fatigue behavior of horizontally curved, steel bridge elements was conducted at Fritz Engineering Laboratory, Lehigh University, under the sponsorship of the Federal Highway Administration (FHWA) of the U.S. Department of Transportation. The multi-phase investigation spanning nearly five years was performed in five tasks. This is the eighth and final report of the project and presents the results of Task 5: development of design recommendations suitable for inclusion in the AASHTO bridge design specifications. The entire project is described and the findings summarized which were presented in the previous project reports.

This report presents the results of fatigue tests of large scale plate and box girder test assemblies. The objectives of the testing program are: (1) to establish the fatigue behavior of welded details on horizontally curved steel plate girder highway bridges, and (2) to compare the fatigue behavior of curved plate girders with straight girder performance to determine if revisions to the AASHTO bridge specification are required.