ORDERED PEAK STATISTICS THROUGH DIGITAL-SIMULATION

A detailed knowledge of the seismic response time history in the form of the first, second, third,... largest peak amplitudes is useful to u nderstand the progressive damage in a structure. This information is h owever not available from the conventionally used response spectra. Th is paper provides a formulation of the statistics of these higher orde r peaks by proposing a digitally simulated joint density function for the peaks in a stationary, Gaussian process. A digital experimentation has been done by generating an ensemble of the single-degree-of-freed om oscillator response to several artificial accelerograms, and the co rresponding ordered peak distributions have been found to be in close agreement with the predictions based on the formulation in this paper. The peak factors based on the proposed formulation have also been com pared with those from the existing formulations based on the Markov th eory and on the assumption of peak independence. It has been found tha t whereas the peak factors from the proposed and Markovian formulation s are compatible, the assumption of independence may give reasonable e stimates only for the first few orders of peaks.