Strength of a corner zone of a frame structure with a hole to prevent from the fatigue crack

This paper deals with a thin-walled steel frame structure having shifted beams used as a pier of the motorway viaduct. Some steel box piers of the motorway viaduct are often faced to a serious problem of the crack due to the fatigue at the beam-to-column connection. To prevent from the development of the crack, sometimes, a hole is arranged at the connection of the beam and the column. Such a hole is certainly effective to the crack, however, in this case, the influence to the buckling strength is not considered. Thus, in the current paper, the buckling strength of the column with a hole at the connection of the beam is studied. The elasto-plastic large deflection FEM analysis is made on the column with the plate thickness and the radius of the hole as parameters. The results indicate that the hole shall decrease the strength of the column up to 9% when the compression stress is arisen near the hole.