ABSTRACT

The damage of steel bridge piers in the 1995 Hyogo-ken Nanbu Earthquake, Japan, can be attributed to cyclic lateral load due to the earthquake coupled with the weight of a superstructure. In the present study, therefore, we carry out the buckling analysis of steel tubes under such a combination of loads. The finite element method is employed, and the steel tubes are modelled by shell and beam elements. Several finite element meshes are constructed for each tube. The difference between the finite element meshes appears in the post-peak deformation behavior where local buckling emerges and develops. However, such difference diminishes, as the mesh becomes finer. When a steel tube of variable cross section is dealt with, the influence of finite element mesh is even larger: a buckling mode may be affected, changing the post-peak behavior of the tube drastically.