A FUNDAMENTAL STUDY ON INELASTIC BEHAVIOR OF H-SECTION STEEL BEAM-COLUMNS UNDER CYCLIC LOADING

Abstract

The objective of the present study is to analytically investigate the inelastic behavior of H-section beam-columns, used in steel bridge structures, under cyclic loading, which will serve as the starting point for development of a seismic performance evaluation method for H-section steel members. Cantilever H-section members with various dimensional and loading parameters are subjected to combined constant axial force and varying lateral loading, both about strong axis and weak axis. The numerical method employed can take into account the effects of local, flexural and lateral-torsional buckling in both monotonic and cyclic loading. Validity of the numerical model is confirmed through comparison with experimental results. The numerical results are then summarized to elucidate the failure mechanisms. The difference of failure modes in cyclic loading from those in monotonic loading is highlighted, which needs to be given particular attention in seismic design of steel structures composed of H-section members.