Fatigue of Curved Steel Bridge Elements - Analysis and Design of Plate Girder and Box Girder Test Assemblies

摘要

This multi-phase investigation involves the performance of five tasks: (1) analysis and design of large scale plate girder and box girder test assemblies, (2) special studies of selected topics, (3) fatigue tests of the curved plate girder and box girder test assemblies, (4) ultimate load tests of the test assemblies, and (5) development of design recommendations suitable for inclusion in the AASHTO design specifications. The first task, analysis and design of horizontally curved plate girder and box girder test assemblies, is contained herein. The research effort centered on fatigue crack propagation at welded details. Examination of design drawings of existing, curved, highway bridges indicated a variety of welded details in current use. In view of the number of details to be tested and the desired test replication, five plate girder test assemblies and three box girder test assemblies were designed to provide stress and deflection conditions typical of actual bridges at the details to be tested. The test assemblies were analyzed using existing, available computer programs. Test assembly design was in accordance with the AASHTO design specifications as modified by the CURT tentative design recommendations. An account of the test assembly design process and the final designs of the test assemblies are included herein.