LOCALIZATION OF PLASTIC BUCKLING PATTERNS UNDER CYCLIC LOADING

This study investigates the theoretical aspects of the localization of plastic buckling patterns, which results in the strength deterioratio n of steel structures under cyclic loading. Because the localization p henomena is caused by the plastic bifurcation from the decreasing equi librium path in the post-peak range, we first presented a method based on the finite-element method (FEM) to analyze the plastic bifurcation . Then, using the proposed method, we analyzed a multiply supported co lumn and simply supported rectangular compression plates subject to re peated loading. As a result of numerical anlysis, it was confirmed the oretically that the localization of buckling patterns has a large infl uence on the strength deterioration under cyclic loading. Furthermore, it was observed from the numerical results that the occurrence of loc alization is accelerated by the accumulation of residual bending defor mations as well as the Bauschinger effect of materials.