Reinforced concrete bridges are common all over the world and are of great importance for transport infrastructure and everyday life. Therefore, it is not surprising that they have recently been an attractive target for terrorist attacks. The most critical element of the bridge is the column because if it collapses, the entire structure loses its load-bearing capacity. More than 50% of terrorist attacks have been carried out with explosive devices, and the most common scenario in attacks on bridges is the placement of explosives in a car under the span structure of the bridge near the column. Based on a review of the State Archives of Croatian Roads and Croatian Highways projects, the most common forms of reinforced concrete columns were filtered out. After preliminary numerical simulations of 9 column shapes in Ansys Autodyn software, a column with a branched rectangular cross-section was selected, designated as P6. Column P6 has the smallest cross-section, retains almost the highest pressures on the front side compared to the other sections, is the most frequent on the Osijek bypass and is dimensioned according to the Yugoslavian standard. The main objective of this doctoral thesis was to determine the resistance (load-bearing capacity) of the selected column to the assumed scenario of an attack with an explosive device. The experimental test was conducted in cooperation with the Croatian Army, which provided the explosives, the space for the experiment and the personnel to handle the explosives. In the doctoral thesis, a concept for experimental tests was developed. After the experimental tests were carried out, the damage to the column was catalogued according to the degree of damage, and it was concluded that the column sufficiently withstood the impact of the assumed amount of explosive that would fit in a medium-sized car. Subsequently, numerical models were created based on the damage pattern and calibrated in the Ansys Autodyn software, which will be used for future analyses of overpass columns under blast loads.