Equivalent linear model for seismic damage evaluation of single-degree-of-freedom systems representing reinforced concrete structures considering cyclic degradation behavior

Abstract

In this study, a novel equivalent damping ratio model that is suitable for reinforced concrete (RC) structures considering cyclic degradation behavior is developed, and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is presented. To this end, Ibarra’s peak-oriented model, which incorporates an energy-based degradation rule, is selected for representing hysteretic behavior of RC structure, and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method, in which the effect of cyclic degradation is considered. Moreover, the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage evaluation. Due to the simplicity of the equivalent linearization method, the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC structures. The verification demonstrates the validity of the proposed method.