Selecting hazard-consistent ground motions for seismic risk analysis: an equivalent earthquake-based methodology

Abstract Seismic risk analysis has received significant attention from both academia and industry in recent years. When conducting seismic risk analyses, selecting hazard-consistent ground motions is crucial. Traditional methods for selecting hazard-consistent ground motions often have limitations, addressing only a few periods and using discrete intensity levels, which can lead to inaccurate risk estimates. This study introduces a novel methodology that overcomes these limitations by using equivalent earthquakes derived from special seismic hazard disaggregation. This approach generates a scenario earthquake set to simulate target response spectra consistent with the seismic hazards of a target site through importance sampling. A selection scheme is also proposed to identify hazard-consistent ground motions from a database. Furthermore, a new method for performing probabilistic seismic demand analysis is presented. A numerical example demonstrates that the selected ground motions maintain strong consistency with the site's seismic hazard curves across a wide range of periods. Unlike traditional methods, this approach does not depend on the fundamental period of specific buildings, making the selected ground motions applicable for accurate seismic risk analysis of multiple structures at the same site.