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Characterization of response spectra through the statistics of oscillator response

Udwadia, F. E. and Trifunac, M. D. (1974) Characterization of response spectra through the statistics of oscillator response. Bulletin of the Seismological Society of America, 64 (1). pp. 205-219. ISSN 0037-1106.

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This paper presents the physical relationships that exist between the response spectra and the Fourier Transform of strong-motion accelerograms through the extreme value statistics of oscillator response. Under the assumption of a stationary response, it has been shown that the spectrum value depends only on two parameters: arms, the root-mean-square-value of the response, and, ɛ, a parameter which measures the distribution of the energy among the various frequencies. The influence of these parameters on the response statistics together with their physical meaning in terms of the oscillator's characteristics have been studied. Comparisons with the Damped Fourier Transform (Udwadia and Trifunac, 1973) computed velocity spectra and the statistically calculated maximum response are presented for three typical accelerograms. The results indicate that response spectra based on statistical computations lead to good first approximations of the actual response to strong ground motion. In addition to characterizing the response spectrum with statistical curves expressing the expected value and the most probable value of the peak response, the 5 and 95 per cent confidence levels are also indicated, thus giving the lower and upper bounds for these statistical spectral estimates. These confidence levels delineate the 90 per cent confidence interval.

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Additional Information:Copyright © 1974, by the Seismological Society of America. Manuscript received May 4, 1973. This research was supported in part by grants from the National Science Foundation and the Earthquake Research Affiliates Program at the California Institute of Technology.
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48409
Deposited By: George Porter
Deposited On:12 Aug 2014 21:54
Last Modified:03 Oct 2019 07:03

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