Curved composite I-girder bridges provide an excellent solution to problems of urban congestion, traffic and pollution, but their behavior is quite complex due to the coupled bending and torsion response of the bridges. Moreover, dynamic behavior of curved bridges further complicates the problem. The majority of curved bridges today are designed using complex analytical methods; therefore, a clear need exists for simplified design methods in the form of empirical equations for the structural design parameters. In this thesis paper, a sensitivity study is conducted to examine the effect of various design parameters on the free-vibration response of curved composite I-girder bridges. To determine their fundamental frequency and corresponding mode shape an extensive parametric study is conducted on 336 straight and curved bridges. From the results of the parametric study, simple-to-use equations are developed to predict the fundamental frequency of curved composite I-girder bridges. It is shown that the developed equations are equally applicable to curved simply supported and composite multi-span bridges with equal span lengths.
PARAMETRIC STUDY OF THE EFFECT OF CROSS-FRAMES AND LATERAL BRACINGS ON FREE VIBRATION RESPONSE OF HORIZONTALLY CURVED I-GIRDER BRIDGES
