Seismic energy factor of self-centering systems subjected to near-fault earthquake ground motions

Abstract

This research focuses on the seismic energy factor of self-centering systems. Based on energy balance concept, the energy factor of self-centering systems is derived. To clarify the influence of hysteretic parameters on the energy factor, nonlinear dynamic analyses of flag-shaped single-degree-of-freedom systems are performed. An ensemble of near-fault earthquake ground motion records is used as excitations. Numerical evaluations considering different combinations of hysteretic nonlinear parameters including the post-yielding stiffness ratio and ductility factor are performed. A comparison with the widely used design spectra is also made. The dispersion of analyses results is also presented. Results indicate that the energy factor of self-centering systems is appreciably influenced by nonlinear parameters (the ductility factor and post-yielding stiffness ratio). Results of this study are instructive for the revelation of the energy balance mode of self-centering systems, and they can be helpful to enhance and improve the current procedures based on energy balance concept.