Seismic behavior of girder bridges

In this thesis, the effect of beam cross-section shape and material on the behavior of beam bridges under the effect of earthquake has been investigated. In the study, precast reinforced concrete I and U-beam, steel I-beam and U beam bridge models with a span of 72 meters were analyzed according to the modal combination method. Spectrum curves were defined according to AASHTO 2012 specification and TBDY 2018 regulations, and a total of eight different models were created, two models for each type of bridge. This thesis study consists of five chapters. In the first part, general information about bridges were given. In the second part, the history of highway bridges, and previous studies on the subject are reviewed. In the third chapter, cross-section and material properties of bridge models, support conditions, dead loads, moving loads and spectrum curves are introduced. In the fourth chapter, according to AASHTO 2012 and TBDY 2018 the findings of the bridge models analyzed under the effect of earthquake are presented and examined in tables and graphs. In the fifth chapter, the results obtained from the thesis study were presented. The values obtained according to the AASHTO 2012 regulation are higher than the values obtained according to the TBDY 2018 regulation. For both regulations, it has been observed that the I section type is more advantageous than the U section type. Keywords: steel beam bridge, reinforced concrete beam bridge, prestressed reinforced concrete bridge, seismic analysis, CSi Bridge