Abstract
Steel piers with octagonal cross-section filled with concrete are often used in practice because of its excellent view and better resistance against wind than the conventional box cross-section, but its seismic design method is not established. The aim of this study is to propose a simplified numerical method for seismic design of such a steel bridge pier. From model tests, stress-strain relations of inner concrete are determined. The equivalent stress-strain relations of the outer steel plate including its local buckling effect are determined from a nonlinear FEM analysis of stub column with octagonal cross-section. The equivalent stress-strain relations are applied to formulate the stiffness matrices in a frame analysis. The accuracy and the efficiency of the proposed method are examined by comparing the numerical results with those of the experimental tests.
