Target roof displacement of degrading moment-resisting frames

Abstract

In application of the nonlinear static procedure or static pushover analysis for estimating seismic demands of building components due to an earthquake ground motion, the peak (target) roof displacement needs to be estimated so as to quantify the global seismic demand. Most of the methods for this estimation are based on using the response of an equivalent single-degree-of-freedom (SDF) system that does not explicitly account for degradation behaviour. Hence, these methods may not be suitable for use in reinforced-concrete (RC) buildings. This study proposes that the equivalent SDF system should include the effects of degradation and its degrading properties can be determined from cyclic pushover analyses. The accuracy of the proposed method is investigated by comparing the peak roof displacements of RC moment-resisting frame buildings estimated by the proposed degrading equivalent SDF systems to the ‘reference’ value determined by nonlinear response history analysis of multi-degree-of-freedom (MDF) syste...