A New Pulse Indicator for the Classification of Ground Motions

Abstract Pulse‐like seismic records constitute a special category of ground motions, because they are capable of causing significant damage to several structures. In this article, a new pulse indicator (PI) for the characterization of seismic motions as pulse‐like or non‐pulse‐like is proposed, which is set equal to the cross‐correlation factor of the significant pulse and the original record. It is suggested that records for which PI is greater than 0.65 are characterized as pulse‐like, whereas records with PI less than 0.55 are characterized as non‐pulse‐like. The method is applied to a total of 221 records that have been characterized in the literature as pulse‐like, non‐pulse‐like, or ambiguous, and the comparison of the new PI with previously proposed indicators is performed. It is also shown that the proposed PI is related to the inelastic response of structures, because records characterized as pulse‐like produce, in general, inelastic displacements larger than the elastic ones. In the presented examples, the Mavroeidis and Papageorgiou wavelet is used for the mathematical representation of the predominant pulse inherent in a record; however, other types of wavelets could also be used. Electronic Supplement: Tables of classification of considered records and proposed pulse indicator (PI) index for records characterized as pulse‐like.