PRECISION OF SPATIAL INTERPOLATION ESTIMATION OF RESPONSE SPECTRA USING THE RECORDS OBSERVED BY YOKOHAMA DENSE ARRAY

Abstract

 SI value is often used as an index of ground motion for disaster estimation. Because source effect and site amplification effect have characteristics which depend on frequency, response spectra are effective in order to calculate the distribution of earthquake ground motion precisely. In the other hand, real-time estimation should be simple. In this paper, using the observation records in Yokohama, response spectra are estimated by the interpolation with the average ratio. It is shown that, 1)response spectrum is effective, 2)average S-wave velocity is well correlated to an amplification factor for the period range from 0.5 to 2.5 second, 3)the use of average ratio of response spectrum gives good estiomation of earthquake ground motion.