Statistical characterization of strong ground motions using power spectral density function

Abstract

abstract The spectral content and duration of some 140 strong-motion accelerograms are studied with an aim of quantifying the uncertainty of ground motion representation. Ground motions are characterized by the parameters of the Kanai-Tajimi spectral density function and by the strong-motion duration. Parameters are estimated for each record based on the method of spectral moments. The statistics and dependencies of the parameters are evaluated, and in particular, correlations between the Kanai-Tajimi parameters, peak ground acceleration, epicentral distance, and local magnitude are investigated. The findings constitute the basis for characterizing seismic input for the purpose of safety assessment of constructed facilities.