Scientific paper ID 2053 : 2020/2

The bridge facilities are of great importance for the logistics and economic activities in our country. Therefore, their vulnerability to natural hazards should be clearly identified and, where possible, reduced. Studies of the seismic resistance of bridge structures are somewhat underestimated compared to those of buildings. The explanation for this fact is the assumption that in an earthquake the possible casualties in buildings are expected to be significantly higher than in the destruction of bridges. This study analyses a reinforced concrete road overpass from the Struma highway. The assessment is done by a set of nonlinear static analyses based on the Finite Element Method. The purpose of calculations is to assess the influence of the substructure to the ductility of the system. Three variants of reinforcement ratio are considered- 1%. 2% и 4%, as well as three types of columns for the substructure- two square sections, two round sections and one rectangular (wall) section. The results are capacity curves for different reinforcement ratio and cross sections. Conclusions are done for the influence of the substructure and the reinforcement’s type in the cross sections.