Inelastic displacement ratio for rocking buildings subjected to far-field and near-field pulse-like ground motions

Self centering rocking buildings are capable of reducing permanent damage and concentrating damage to replaceable energy dissipation devices. This paper aims to calculate inelastic displacement ratio for self centering rocking buildings under far field and near field pulse like ground motions. In this paper, the inelastic displacement ratio, i.e. the ratio of the maximum inelastic displacement to the maximum displacement of the elastic system, for self centering rocking systems are determined using nonlinear dynamic time history analysis. The effects of seismic and modeling parameters on the inelastic displacement demands of self centering rocking buildings are also evaluated. Findings show that the effect of the pulse period of ground motions, predominant period of ground motions, and modelling parameters (i.e. response modification factor, hardening ratio, and energy dissipation ratio) on the inelastic displacement ratio are considerable, while influences of the other parameters such as distance to the fault site, ground motion magnitude, and the soil site are less on the analysis results. Finally, using a two-stage regression on the statistical results, new equations are proposed for estimation of the scaled and unscaled (code base) constant strength spectra of self centering rocking buildings under far field and near field pulse like ground motions.