This thesis analyzes the stability of a two-part composite column through experimental, analytical, and numerical approaches. The analyzed column consists of two steel plates connected by two rows of bolts. Due to the clearance in the bolt holes and the deformability of the bolts, such a connection is flexible, and its efficiency needs to be determined. First, the problem is theoretically addressed, defining the cross-section type and the expected theoretical limits of the critical buckling force. Following that, an experiment was conducted where the column was subjected to axial compression, with measurements of force and displacement (both axial and lateral) taken before and after the column loses stability. In the next step, geometrically nonlinear planar (2D) and spatial (3D) numerical models were developed to simulate the experiment, allowing the column (with an initial imperfection) to buckle under compressive force. The models assumed that the bolts were deformable and that the connection between the bolts and the steel plates was rigid. Finally, the results of the experiment, analytical calculations, and numerical simulations were compared to verify the accuracy and reliability of the models. It was found that, due to unforeseen displacements of the sample during testing and a lower actual degree of connection than that predicted by the model, there were certain discrepancies between the analytical calculations, numerical models, and the experiment.