In seismic risk assessment, a ground motion intensity measure is used as an intermediate variable to relate ground motion severity to economic loss. However, using a single intensity measure can exclude other important information, reducing accuracy. Many previous studies focus on the suitability of intensity measures from a structural response perspective, but few examine their impact on seismic risk. This study quantitatively evaluates how intensity measure selection affects risk estimates and proposes suitable measures. Results show that spectral acceleration at a building’s natural period is appropriate. Spectral acceleration at one second and peak ground velocity are also useful, cost-efficient alternatives.
