Seismic Site Response Analysis Leading to Revised Design Response Spectra for Australia

Abstract

This study explores the effects of local site conditions on seismic site response and investigates the validity of the site classification system and the response spectra in codes, with a focus on the Australian earthquake loading standard. The results show that the averaging process used to derive the design spectra in existing codes has led, in general, to an underestimation of the site response. A new systematic method is proposed for obtaining the displacement response spectra based on the correlations between the initial and degraded fundamental natural site period and amplification factors. Modifications to the site classification system are also recommended.