In the thesis, we designed, analyzed and dimensioned a prestressed reinforced concrete bridge over the Sava Dolinka River in the village of Piškovca. The bridge structure is made of high-strength concrete. Depending on the environmental conditions, we have determined the external influences that affect the structure and described the rheological processes in high-strength concrete. We also determined the traffic load on the bridge. In the preliminary analysis, the thickness of the concrete cover layer was selected, the shape and dimensions of the cross-section of the bridge were determined, as well as the required number of prestressed tendons. We used a variable cross-section and analyzed the construction for ultimate limit state and serviceability limit state. In the analysis, we also determined the losses of prestressing force in the tendons, calculated the required tensile force at the anchor head, and performed a global stability analysis of the structure.
Based on the results of the analysis, we first checked the axial-flexural and shear resistance of the structure in the transverse direction (perpendicular to the axis of the carriageway) and determined the required reinforcement. In the of serviceability limit state we checked the level of stresses and width of the cracks. Then we checked the axial-flexural and shear resistance of the structure in the longitudinal direction. At the same time, we also checked the load bearing capacity of the working contact of concrete. In the serviceability limit states, we checked the level of stresses and displacements of the structure. All controls were performed using Sofistik software (SOFiSTiK AG, 2018). We have found that with the material and geometric parameters and the degree of prestress determined in the framework of the preliminary analysis of the bridge structure, in the global analysis, we satisfy all the performed checks of the limit states of the structure.
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