Hilbert–Huang-Transform-Based Seismic Intensity Measures for Rocking Response Assessment

Structures that can uplift and rock under severe seismic excitations present remarkable stability without exhibiting damage. As such, rocking-response-based structural systems constitute a promising design practice. Due to the high nonlinearity of the rocking response, the seismic performance of this class of structures should be evaluated probabilistically. From this point of view, in the present study, the performance of 12 novel HHT-based intensity measures (IMs) in describing the seismic behavior of typical rocking viaducts was assessed based on optimal IM selection criteria. To this end, a comparative evaluation of the performance between the proposed and 26 well-known conventional IMs was presented. Moreover, bivariate IMs were also considered, and seismic fragilities were provided. Finally, the classification of the seismic response was conducted using discriminant analysis, resulting in a reliable and rapid estimation of the maximum seismic demand. Based on the results, it is evident that HHT-based IMs result in an enhanced estimation of the seismic performance of the examined structural system.