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Recent developments in displacement-based design methodologies have increased the need for reliable displacement design spectra, especially in long periods. The design spectra proposed in Eurocode 8 are assessed, using recent attenuation relationships that predict response spectral ordinates based on European data, as well as five selected European strong motion accelerograms. To identify possible trends in long-period spectral displacements, several high-quality digital recordings from the 1995 Hyogoken-Nanbu (Kobe) earthquake were collected and studied. Based on the differences recognised, possible modifications for the design spectrum to take into account in future revision of Eurocode 8 are proposed.

Extensive areas worldwide, many of them heavily urbanized, are susceptible to seismic risk, that is, the probability that people will suffer loss and that their built environment will be damaged. Due to our deficient knowledge of nature and to financial reasons, seismic risk cannot be eliminated. Societies accept a certain level of seismic risk, which depends mainly on culture and information available. The difference between actual and acceptable seismic risk can and should be managed. Engineers can offer several technological remedies for most seismic hazards and can minimize vulnerability by applying advanced design and construction reducing susceptibility to strong ground motion of any structure. They can also contribute to seismic risk reduction by informing, educating, and organizing communities. In their effort to reduce seismic risk, engineers face major challenges. Although the trend in the number of lives lost each year to catastrophic seismic events is decreasing in some countries, but not in others, the corresponding costs are continuing to increase rapidly. Today, the globalization of trade and commerce enhanced by wide-ranging transportation systems and modern communications had as result the impact of a damaging earthquake to reach far beyond the epicentral region.