State-of-the-Art for Assessing Earthquake Hazards in the United States. Report 14. Representation of Earthquake Ground Motion: Scaled Accelerograms and Equivalent Response Spectra.

Abstract : Alternative representations of earthquake ground motion for the purpose of seismic analysis and design are reviewed and critically examined, with emphasis on the relation between earthquake time histories and response spectra. The results of a study on the effects of scaling earthquake records on peak acceleration are presented. Errors attributable to scaling are evaluated in terms of the response for one-degree elastic and elasto-plastic systems and the equivalent number of cycles of uniform shear stress. The significance of duration and frequency content is assessed in this context. The pitfalls of the practice of using 'standard' design response spectra are pointed out, and methodology is proposed for developing site-specific design response spectra based on appropriate accelerograms from past earthquakes. (Author)