Cyclic Loading Characteristics of Nonlinear-Ductile Systems

Abstract To investigate loading characteristics of cyclic loads subjected to nonlinear-ductile systems, the responses of single-degree-of-freedom systems with several types of restoring forces due to harmonic excitations are drawn on the constant-ductility response spectra and the maximum force-deformation diagrams. Based on the spectra and diagrams, cyclic loadings on nonlinear-ductile systems are categorized into force- or deformation-controlled loadings using the critical normalized natural periods. Furthermore, the relationship between the constant-ductility response spectrum and the maximum force-deformation diagram is clarified.