This study proposes a generalized hysteresis model based on Bézier curves that represents restoring force characteristics of reinforced concrete, steel, and timber structures. The skeleton and unloading/reloading curves are formulated using Bézier control points, allowing a unified and flexible description of nonlinear hysteresis. Characteristic control points and parameter ranges are defined for each structural type to ensure physical consistency. The model can express strength degradation, pinching, and slip behavior, enabling accurate reproduction of diverse hysteretic responses. Its effectiveness is demonstrated through comparisons with experimental data and applications to representative structural hysteresis loops.
NAGASE et al. (Sun,) studied this question.