Generation of fully non-stationary random processes consistent with target seismic accelerograms. Issue 141 (February 2021)

• Record Type: Journal Article
• Authors: Muscolino, G.; Genovese, F.; Biondi, G.; Cascone, E.
• Is Part Of: Soil dynamics and earthquake engineering. Issue 141(2021)
• Publication Date: 2021-02
• Subjects: Artificial accelerograms -- Fully non-stationary stochastic process -- Evolutionary power spectral density function -- Real ground motion records -- Simulation; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2020.106467
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: In this paper, a method for generating samples of a fully non-stationary zero-mean Gaussian process, having a target acceleration time-history as one of its own samples, is presented. The proposed method requires the following steps: i) divide the time axis of the target accelerogram in contiguous time intervals in which a uniformly modulated process is introduced as the product of a deterministic modulating function per a stationary zero-mean Gaussian sub-process, whose power spectral density ( PSD ) function is filtered by two Butterworth filters; ii) estimate, in the various time intervals, the parameters of modulating functions by least-square fitting the expected energy of the proposed model to the energy of the target accelerogram; iii) estimate the parameters of the PSD function of the stationary sub-process, once the occurrences of maxima and of zero-level up-crossings of the target accelerogram, in the various intervals, are counted; iv) obtain the evolutionary spectral representation of the fully non-stationary process by adding the various contribution evaluated in the various intervals. Highlights: The generation of artificial accelerograms consistent with real seismic records is addressed. Main characteristics of target accelerograms are used to define fully non-stationary processes. The target accelerogram is considered a sample of the fully non-stationary process. The proposed method is suitable for selecting input motion for dynamic analyses of structural and geotechnical systems. The proposed procedure is characterised by accuracy and computational efficiency.