Aims & Scope
Editorial Board
Contents & Abstracts
Submitting Your Paper
Copyright & Permissions
Contact Us
Subscriptions
search

Characteristics of response spectra for long-periods of main-shock recordings of the Chi-Chi earthquake

Chen Yong (³Β ΣΒ) and Yu Yanxiang (ΣαΡΤΟι)

Institute of Geophysics, China Earthquake Administration, Beijing 100081, China

Abstract: Current practice uses predictive models to extrapolate long-period response spectra based on far-field recordings in moderate and weak earthquakes. However, the spectra are not long enough and the data are often not reliable, which means that the seismic design code cannot accurately define seismic design requirements for long-period structures. The near-field recordings in the main-shock of the Chi-Chi earthquake have a large signal-to-noise ratio (SNR), which makes them suitable for studying the long-period acceleration response spectrum up to 20 sec. The acceleration response spectra from 246 stations within 120 km of the causative fault are statistically analyzed in this paper. The influence of distance and site conditions on long-period response spectrum is discussed, and the shapes of the amplification spectra are compared with the standard spectra specified in the seismic design code of China. Finally, suggestions for future revisions to the code are proposed.

Keywords: long-period; main-shock recordings; Chi-Chi earthquake; signal-to-noise ratio; acceleration response spectrum; amplification spectrum