Influence of earthquake types on the design of seismic-resistant steel structures. Part 1: Challenges for new design approaches

The paper presents a critical point of view concerning current design methodologies for steel structures, based mainly on response spectra, which cannot consider many important aspects (i.e. near-fault effects, earthquake durations and number of important cycles). This methodology ignores the progress of Seismology and Engineering Seismology Science in the knowledge of fault mechanisms and earthquake types. A classification of design seismic actions in function of these faults mechanisms are proposed for inter-plate earthquakes, produced along the boundaries of tectonic plates, inland earthquakes, occurring in the zones between these boundaries and intra-slab earthquakes, produced in the deep zones of subduction plates. Differences in seismic actions and main structural problems for these earthquake types are presented in the companion paper (Gioncu & Mazzolani, 2006a), showing the demanded directions of future researcher works in order to improve the design seismic codes.