An evaluation of the strength characteristics of horizontally curved steel I-girder bridges

Horizontally curved bridges occupy a growing number of the steel bridge population in the United States today because they are often one of the few options available for difficult roadway alignments. Horizontally curved bridges offer aesthetic and economic benefits over comparable straight-chorded bridges. However, there are additional design, analysis and construction issues to consider for horizontally curved bridges compared to the design of straight-chorded bridges.; To ensure uniform standards and safety requirements, the FHWA created the Consortium of University Research Teams (CURT) in 1969 to conduct research on horizontally curved girders and develop guide specifications for design. In a cooperative research effort to further investigate horizontally curved bridges and improve the design specifications initially developed from the CURT project, the FHWA initiated the Curved Steel Bridge Research Project (CSBRP) in 1992. The CSBRP tested a full-scale three-girder system.; This thesis focuses on extensive finite element analysis (FEA) conducted on the CSBRP test specimens. FEA of the noncomposite bending components and the composite test bridge were conducted. Results of the FEA are used to examine the strength characteristics of horizontally curved I-girders. The 2004 AASHTO LRFD Bridge Design Specifications were used to determine if significant design economy can be achieved if horizontally curved I-girders are permitted to use the Mp-based design limits. Comparisons are made between the 2003 AASHTO Guide Specifications for Horizontally Curved Bridges and the 2004 AASHTO LRFD Specifications to determine the accuracy of these guidelines for predicting the capacity of horizontally curved I-girder bridges.