A NOVEL METHOD FOR THE GENERATION OF FULLY NON-STATIONARY SPECTRUM COMPATIBLE ARTIFICIAL ACCELEROGRAMS

The increasing availability of strong motion records makes the use of real accelerograms an attractive option for a proper definition of the input motions in the dynamic analysis of struc-tural and geotechnical systems. Despite different real accelerograms selection procedures have been proposed in the literature, there are situations in which it may be impossible to select a suitable code-required number of accelerograms without applying large scale factors which distort the actual characteristics of selected motions leading to unrealistic input. In these situ-ations, the use of artificial accelerograms could represent a possible alternative. A novel procedure for generating fully non-stationary spectrum compatible artificial accelero-grams, is presented in this paper. Depending on the aim to be achieved, it is possible to obtain the spectrum-compatibility be-tween the generated samples and the target action in terms of response spectrum or Fourier spectrum, using two different corrective Power Spectral density function terms. A numerical application shows the validity of the generation procedure and the accuracy of the model in reproducing realizations with statistical characteristics similar to those of the target motion.