Seismic hazard maps in Serbia

Mapping seismic hazard parameters for use in earthquake-resistant design must satisfy the guidelines for performance-based design (PBD). At present, PBD requires specification of two spectral amplitudes, one in which the structure will remain essentially linear, with system period T-linear,T- and the other in which it may undergo a nonlinear response and will vibrate with longer-system period T-nonlinear. These requirements cannot be satisfied via one (same) fixed spectral shape, and such spectra cannot be scaled by peak ground acceleration. Another source of difficulty in the selection of the PBD-design amplitudes occurs when the standard spectrum shape is not capable of describing excitation from large distant earthquakes. In this paper we illustrate these problems by examining Serbia seismic hazard maps and show that scaling design ground motion via peak ground acceleration and fixed shape spectra lead to serious underestimation of long-period spectral amplitudes. We show how mapping of seismic hazard based on our method, which uses Uniform Hazard Spectra (UHS) eliminates these difficulties.