The Effect of Seismic Loading Simulation on the Response Variability of Structures

Abstract

Abstract. This paper investigates the variability of the seismic response of structures subjected to various ensembles of ground motions in the framework of nonlinear dynamic analysis. In this kind of analysis, seismic loading, introduced in the form of excitation accelerograms, constitutes the most important source of uncertainty, as it depends on a number of random factors (e.g. distance from the fault source, magnitude, local soil conditions). In order to quantify the effect of seismic loading simulation on the response variability of structures, nonlinear dynamic analysis is carried out on a steel frame, subjected successively to three ground motion ensembles. The ensembles comprise, respectively, real ground motions and artificial accelerograms generated by two different algorithms, one in accordance with the Code provisions and one targeted to a more realistic simulation of the seismic event. Comparison of the three approaches is made by monitoring the statistical properties of the maximum displacement and interstorey drift induced by the assumed ensembles.

Estimation of Evolutionary Power Spectra of Seismic Accelerograms

“…• As demonstrated in [11], the algorithm achieves in most cases a very good match of the response spectrum of the input earthquake although it has not been developed with the aim of producing spectrum-compatible accelerograms. It is capable of delivering spectra that can satisfactorily be adapted to the Eurocode 8 design spectrum although the values of the maximum spectral accelerations of most spectra are smaller than the regulatory range for a particular combination of parameters.…”