ON INELASTIC RESPONSE SPECTRA OF PULSE‐TYPE GROUND MOTION BASED ON DECOMPOSITION METHOD

Abstract

AbstractThis article aims to investigate the influence of different frequency components on the amplitude parameters and inelastic response spectral characterizations of pulse‐type ground motions. 53 pulse‐type ground motions selected from 12 large earthquakes are utilized in this study. First, the high frequency components (HFC) and low frequency components (LFC) of these ground motions are obtained based on multi‐scale decomposed method. To compare with the results obtained by traditional methods, the predominant component (PC) which can be used as the representation of the dominant velocity pulse and the residual component (RC) which is obtained by removing the PC from original ground motion are analyzed. Second, the comparison of the amplitude parameters and the inelastic response spectra between original ground motions and four kinds of ground motion components (HFC, LFC, PC, and RC) is performed in order to investigate the influence of ground motion components on the amplitude parameters and inelastic response spectral characterizations of the corresponding original ground motions. Finally, a harmonic ground motion model is used to explore the reasons for the special inelastic response spectral characterizations for pulse‐type ground motions. Analysis results show that low‐frequency component is not only the major factor that influences the velocity and displacement amplitude of pulse‐type ground motion but also can cause considerable influence on the acceleration amplitude of original ground motion. It is also the immediate causes of the larger inelastic displacement ratio and the smaller inelastic strength reduction factor for pulse‐type ground motions. That will result in higher displacement and strength demands for building structure when the structure is subjected to pulse‐type ground motions.