Experimental study on H-section steel beam-columns under cyclic biaxial bending considering the effect of local buckling

摘要

Due to multidirectional ground motions generated by earthquakes, structural members will be subjected to biaxial bending effects, where the occurrence of yielding and/or buckling about one principal axis induces unfavourable deteriorations about the other principal axis. The experimental research on cyclic biaxial bending behavior of steel H-section members is conducted. A specially designed "3D-hinge-sliding" testing system composed of a universal rotatable hinge and three sliding devices is established to apply the axial force and cyclic biaxial moments to the specimens. Eleven steel H-section beam-columns with different width-thickness ratios for the flanges and webs, together with different axial force ratios and loading directions are employed. Measures of performance, including failure mechanism, interaction curves, ductility and energy absorption capacity, have been extracted from the measured data. The responses are found to be strongly influenced by the interactions between the local buckling and plastic deformation effects of the plate elements.