ABSTRACT
Shown in Figure 1 are the idealized hysteresis curves of a conventional ductile system (left) and
two basic inelastic models were developed, with one having NSC behavior and the other having SC behavior. Both models have the same bilinear backbone curves, i.e., the same initial stiffness, the same yield point, and the same post-yield stiffness, see Figure 1. SC models with different energy dissipating capacities, i.e., different β values, were analyzed and results were compared. In OpenSees, the uniaxial material type STEEL01 was used for the NSC model, and the uniaxial material type SelfCentering was used for the SC models. The one dimensional zero-length element type zeroLength was used to construct the single degree-of-freedom models. All the models have an initial stiffness of 1000 N/m, a mass of 6.332 kg, which result in an elastic structural natural period of 0.5 s. The postyielding stiffness of the inelastic models is 15% of the initial stiffness. A 5% Rayleigh damping was incorporated in all the models. For SC models, three β values, 0.4, 0.6, and 0.8 were used to investigate the effects of different energy dissipating capacities.
