STUDY ON VALUE AND ENERGY CHARACTERISTICS OF DESIGN SPECTRA IN LONG PERIOD RANGE

The process of calculating input energy spectrum from Fourier amplitude spectrum and the correlation between power spectral density and acceleration response spectrum on the basis of random vibration theory are introduced. The approach of calculating the input energy spectra compatible with design acceleration response spectrum is proposed based on the above theory. The synthetic input energy spectrum is calculated to match the design spectrum of “Code for aseismic design of buildings (GB 50011-2010)”. The input energy characteristics of design acceleration response spectra in long-period ranges are analyzed through comparing with the input energy spectra of real accelerograms. The results show that the input energy increases with the period in the long-period range, which are significantly different from the feature of real accelerograms. A revision for the design spectra in long-period ranges is recommended according to the characteristics of the input energy spectra of real accelerograms.