New intensity measure parameter based on record's velocity characteristics

Abstract

Hazard analysis is the prominent stage in performance-based earthquake engineering and properintensity measure selection is itssignificant phase. Despite diversity in recently proposed intensity measures, there are still significantvariations in the magnitude of structural responses used to assess performance especially according to the records with pulse-like characteristicsIn this study, several intensity measures for two groups of records, far-field and near-field, were evaluated in six scaling levels. In addition, a new scalar intensity measure,accounting for pulse-like characteristics of near-field records, have been generated based on spectral velocity at first-mode period of a structure and maximum amount of velocity. Utilized structural models are steel moment frames with different heights accounting for the effects of wave propagation.It is discovered that this new velocity-based intensity measure is the most convenient IM factor especially forthe stories under pulse propagation associated with near-field records,considering both efficiency and sufficiency aspects. Furthermore, it is found that utilizingnonlinear spectral values doesnot significantly amplify assessment precision in the moderate range of intensity measures, and considering their unavoidably complicating and timeconsuming required analyses; elastic spectral valuescan be adequately substituted.