PROPOSED EARTHQUAKE DESIGN SPECTRA FOR EASTERN AND CENTRAL IRAN

Based on available records and information from eastern and central Iranian earthquakes, a total of 39 accelerograms were selected to arrive at design spectra for two geological site conditions. Two general categories of stiff and soft soil with 11 and 28 records were considered, respectively, The procedure is similar to that used by Newmark et al [1] The frequency regic;ns to which normalization with respect to peak ground displacement, peak ground velocity, and peak ground acceleration are performed, were determined for the new data, Our results show significant reduction in the amplification values in the long-period region when compared to the recently proposed Iranian seismic code BI-IRC-2800 [2], design spectra