Generation of spectrum-compatible earthquake ground motions considering intrinsic spectral variability using Hilbert–Huang transform

A new approach is presented for generating a desired number of earthquake ground motions, which are compatible with a target seismic design spectrum for building structural design, based on a small number of actual earthquake records. This set of spectrum-compatible earthquake ground motions is generated by using Hilbert–Huang transform and solving related optimization problems. The matrix of correlation coefficients of spectral accelerations of the generated earthquake ground motions closely matches the target spectral correlation matrix predicted by the Next Generation Attenuation Project. The generation procedure preserves the non-stationary characteristics of seed actual earthquake records and ensures the intrinsic aleatory variability of real ground motions for a given scenario earthquake.