Nonlinear Earthquake Response Analysis Using Causal Hysteretic Damping and Extended Rayleigh Damping

In dynamic design, damping considerably influences the response of structures, so it must be set appropriately. Stiffness-proportional damping is generally used as an inherent damping model, but this model tends to overestimate the damping of higher-order modes. Certain models can evaluate the damping of higher-order modes, such as modal damping and Rayleigh damping. One of the authors proposed causal hysteresis damping and extended Rayleigh damping as damping models with a low frequency dependence of the damping ratio. However, although the use of these models for linear analysis has been studied, their application to nonlinear analysis has not been sufficiently studied. Therefore, in this paper, the effect of these inherent damping models on the response characteristics of structures was evaluated to obtain basic data for future research. Specifically, stiffness-proportional damping, Rayleigh damping, modal damping, causal hysteresis damping, and extended Rayleigh damping were studied. Their response characteristics were evaluated and compared. These damping types for nonlinear analysis could be divided into the initial type and the tangential type, depending on how to handle changes in stiffness. These properties were also examined.