Main Article Content
The study of the structural behavior of bridges in high-speed railways, not short ago, is one of the main data references on which designers and maintenance teams rely in this field. Many studies have been conducted on this matter. Studies in recent years focused on showing the effect of some or one of the characteristics of the model to know its effect on the dynamic behavior of the structure. Most of the studies did make a comparison between different types of moving loads, or between the ballast paths and the paths free of it. This research focused on clarifying the effect of changing the cross-sectional shape of the bridge and making a comparison between the results of the dynamic analysis of two models, the first with a solid cross-section, and the second is a ribbed. The analysis was carried out using SAP2000 software. The results showed differences in the dynamic behavior parameters of the two bridge models. At MS1 the vertical acceleration and displacement values were highest in the solid cross-section with approximate values of 2.5 m/s2 and 2.06 mm respectively, while at MS2 the higher values happened in the ribbed cross-section is 1.92 m/s2 and 1.58 mm respectively. Conclusions were made about the effects of section change on dynamic behavior at different speeds.