Earthquake Time Histories and Response Spectra

The problem of the design of hypothetical earthquakes to be compatible with given target spectra is examined first. With the tools provided by this introductory study, the earthquake response problems of structure, and of equipment mounted therein, are examined both by time history and frequency domain analysis methods. Remaining totally in the frequency domain, so-called ground and floor response spectra are developed and compared to results obtained by the more usual time-domain analysis. The study emphasizes throughout the Fourier spectral aspects of earthquake response analysis and tends in particular to elucidate some basic issues involved in the development of floor response spectra.